U.S. patent application number 14/921898 was filed with the patent office on 2016-04-28 for preparations of meta-iodobenzylguanidine and precursors thereof.
This patent application is currently assigned to MOLECULAR INSIGHT PHARMACEUTICALS INC.. The applicant listed for this patent is Molecular Insight Pharmaceuticals Inc.. Invention is credited to Jason Moss, Machinani Rao.
Application Number | 20160115267 14/921898 |
Document ID | / |
Family ID | 55174697 |
Filed Date | 2016-04-28 |
United States Patent
Application |
20160115267 |
Kind Code |
A1 |
Moss; Jason ; et
al. |
April 28, 2016 |
PREPARATIONS OF META-IODOBENZYLGUANIDINE AND PRECURSORS THEREOF
Abstract
The present disclosure provides purified forms of iobenguane and
preparations of a precursor to iobenguane, such as a polymer, the
polymer comprising a monomer of formula (I) ##STR00001## or a
pharmaceutically acceptable salt thereof, the preparation
comprising leachable tin at a level of 0 ppm to 850 ppm.
Inventors: |
Moss; Jason; (Tarrytown,
NY) ; Rao; Machinani; (Tarrytown, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Molecular Insight Pharmaceuticals Inc. |
Tarrytown |
NY |
US |
|
|
Assignee: |
MOLECULAR INSIGHT PHARMACEUTICALS
INC.
Tarrytown
NY
|
Family ID: |
55174697 |
Appl. No.: |
14/921898 |
Filed: |
October 23, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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62069029 |
Oct 27, 2014 |
|
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|
62068598 |
Oct 24, 2014 |
|
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Current U.S.
Class: |
424/78.34 ;
514/634; 526/240; 564/237 |
Current CPC
Class: |
A61K 51/0406 20130101;
A61P 35/00 20180101; C08F 230/04 20130101; C07C 279/06
20130101 |
International
Class: |
C08F 230/04 20060101
C08F230/04; C07C 279/06 20060101 C07C279/06 |
Claims
1. A preparation comprising a polymer, the polymer comprising a
monomer of formula (I): ##STR00033## or a pharmaceutically
acceptable salt thereof, wherein leachable tin is present in the
preparation at a level within a range of about 0 ppm to about 150
ppm.
2. The preparation of claim 1, wherein the pharmaceutically
acceptable salt is the HOAc salt.
3. The preparation of claim 1, which preparation is enclosed in a
container under inert gas.
4. The preparation of claim 3, wherein the inert gas is
nitrogen.
5. The preparation of claim 1, wherein the level of leachable tin
is within a range of about 0 ppm to about 120 ppm.
6. The preparation of claim 1, wherein the level of leachable tin
is within a range of about 0 ppm to about 50 ppm.
7. The preparation of claim 1, wherein the polymer comprising
monomer of formula (I), or the pharmaceutically acceptable salt
thereof, makes up at least 98% of the preparation.
8. The preparation of claim 1, the preparation comprising less than
1.5 wt % water relative to the wt % of the preparation.
9. The preparation of claim 1, the preparation comprising less than
1.0 wt % water relative to the wt % of the preparation.
10. The preparation of claim 1, the preparation comprising less
than 0.5 wt % organic solvent relative to the wt % of the
preparation.
11. The preparation of claim 1, the polymer comprising less than
about 0.5 wt % of a monomer of formula (IV): ##STR00034## or a
pharmaceutically acceptable salt thereof.
12. The preparation of claim 1, the polymer comprising less than
about 0.5 wt % of a monomer of formula (V): ##STR00035## or a
pharmaceutically acceptable salt thereof.
13. A kit comprising a preparation, the preparation comprising a
polymer comprising a monomer of formula (I): ##STR00036## or a
pharmaceutically acceptable salt thereof, wherein leachable tin is
present in the preparation at a level within a range of about 0 ppm
to about 150 ppm, and the kit further comprising a container that
stores the polymer comprising monomer of formula (I) under inert
gas.
14. The kit of claim 13, comprising any one of the preparations of
claims 2-12.
15. The kit of claim 13, wherein the purified polymer comprising
monomer of formula (I), or salt thereof, is least 98 wt % pure, for
at least six months at -20.degree. C.
16. The kit of claim 13, wherein the kit maintains leachable tin
content at a level of less than 150 ppm for at least six months at
-20.degree. C.
17. The kit of claim 13, wherein the kit maintains leachable tin
content at a level of less than 20 ppm for at least nine months at
-20.degree. C.
18. The kit of claim 13, comprising less than 1.5 wt % water
relative to the wt % of the preparation.
19. The kit of claim 13, comprising less than 1.0 wt % water
relative to the wt % of the preparation.
20. A pharmaceutical composition comprising: (a) a compound of
formula (VI): ##STR00037## or pharmaceutically acceptable salts
thereof, wherein R.sub.1 is a radioisotopic label, and the compound
of formula (VI) is formed by contacting a radioisotope of a halogen
ion with a preparation of a polymer comprising monomer of formula
(I): ##STR00038## or a pharmaceutically acceptable salt thereof,
the preparation of the polymer comprising monomer of formula (I)
comprising leachable tin at a level of 0 ppm to 150 ppm; and (b) a
pharmaceutically acceptable carrier, adjuvant, or vehicle.
21. The pharmaceutical composition of claim 20, comprising the
preparation of claim 2.
22. The pharmaceutical composition of claim 20, wherein the
radioisotope of a halogen ion is fluoride, bromide, iodide or
astatine.
23. The pharmaceutical composition of claim 20, wherein the
radioisotope of a halogen ion is .sup.123I, .sup.124I, .sup.125I or
.sup.131I.
24. The pharmaceutical composition of claim 20, wherein the
radioisotope of a halogen ion is .sup.211At.
25. A pharmaceutical composition comprising: (a)
meta-iodobenzylguanidine (MIBG): ##STR00039## or a pharmaceutically
acceptable salt thereof, wherein MIBG is formed by contacting an
iodide salt with a preparation of a polymer comprising monomer of
formula (I): ##STR00040## or a pharmaceutically acceptable salt
thereof, the preparation of the polymer comprising monomer of
formula (I) comprising leachable tin at a level of 0 ppm to 150
ppm; and (b) a pharmaceutically acceptable carrier, adjuvant, or
vehicle.
26. The pharmaceutical composition of claim 25, comprising the
preparation of claim 2.
27. The pharmaceutical composition of claim 25, wherein not more
than about 0.5 wt % meta-iodobenzylamine (MIBA): ##STR00041## or a
pharmaceutically acceptable salt thereof, is present in the
composition.
28. The pharmaceutical composition of claim 25, wherein not more
than about 0.5 wt % meta-iodobenzylbiguanidine (MIBBG):
##STR00042## or a pharmaceutically acceptable salt thereof, is
present in the composition.
29. The pharmaceutical composition of claim 25, wherein not more
than about 0.5 wt % meta-hydroxybenzylguanidine (MHBG):
##STR00043## or a pharmaceutically acceptable salt thereof, is
present in the composition.
30. The pharmaceutical composition of claim 25, wherein not more
than about 0.5 wt % meta-iodobenzylamine (MIBA),
meta-iodobenzylbiguanidine (MIBBG), and/or
meta-hydroxybenzylguanidine (MHBG): ##STR00044## or
pharmaceutically acceptable salts of any thereof, is present in the
composition.
31. A pharmaceutical composition comprising: a compound of formula
(VI): ##STR00045## or pharmaceutically acceptable salts thereof,
and a pharmaceutically acceptable carrier, adjuvant, or vehicle;
wherein R.sub.1 is a radioisotopic label; the pharmaceutical
composition comprising leachable tin at a level of 0 ppm to 150
ppm.
32. A pharmaceutical composition comprising:
meta-iodobenzylguanidine (MIBG): ##STR00046## or pharmaceutically
acceptable salts thereof, and a pharmaceutically acceptable
carrier, adjuvant, or vehicle; the pharmaceutical composition
comprising leachable tin at a level of 0 ppm to 150 ppm.
33. A method for preparing a purified composition of a polymer
comprising monomer of formula (I): ##STR00047## or a
pharmaceutically acceptable salt thereof, the method comprising the
steps of: solvent-treating a preparation comprising the polymer or
pharmaceutically acceptable salt thereof, by contacting the
preparation with a solvent, and then removing substantially all of
the solvent so that a solvent-depleted material comprising the
polymer, or pharmaceutically acceptable salt thereof, is generated;
and subjecting the solvent-depleted material to vacuum, and to a
temperature within a range of about 30.degree. C. to about
50.degree. C., the subjecting being performed under conditions and
for a time sufficient so that not more than about 150 ppm of
leachable tin is present and, therefore, a purified composition of
the polymer, or pharmaceutically acceptable salt thereof, has been
produced.
34. The method of claim 33, wherein the solvent is or comprises an
alcohol.
35. The method of claim 34, wherein the alcohol is or comprises
ethanol.
36. The method of claim 33, wherein the step of solvent-treating
the preparation comprises first and second solvent-treating steps,
performed with first and second solvents, wherein the first solvent
is an aqueous alcohol and the second solvent is an anhydrous
alcohol.
37. The method of claim 36, wherein the first solvent is aqueous
alcohol and the second solvent is anhydrous ethanol.
38. The method of claim 33, the purified composition comprising
less than 1.5 wt % water relative to the wt % of the
composition.
39. The method of claim 33, the purified composition comprising
less than 1.0 wt % water relative to the wt % of the
composition.
40. The method of claim 33, further comprising a step of: storing
the purified composition under an inert gas.
41. A method for preparing meta-iodobenzylguanidine (MIBG):
##STR00048## or a pharmaceutically acceptable salt thereof, the
method comprising steps of: contacting an iodide salt with a
preparation comprising a polymer comprising monomer of formula (I):
##STR00049## or a pharmaceutically acceptable salt thereof, the
preparation being substantially free of leachable tin such that
leachable tin is present in the preparation at a level below 150
ppm.
42. The method of claim 41, wherein the step of contacting
comprises contacting with a preparation as set forth in claim
2.
43. The method of claim 41, wherein the iodide salt is sodium 1-131
iodide.
44. A method comprising administering to a subject a pharmaceutical
composition comprising: (a) meta-iodobenzylguanidine (MIBG):
##STR00050## or a pharmaceutically acceptable salt thereof, wherein
MIBG is formed by contacting an iodide salt with a preparation of a
polymer comprising monomer of formula (I): ##STR00051## or a
pharmaceutically acceptable salt thereof, the preparation of the
polymer comprising monomer of formula (I) comprising leachable tin
at a level of 0 ppm to 150 ppm; (b) a pharmaceutically acceptable
carrier, adjuvant, or vehicle.
45. The method of claim 44, wherein the pharmaceutical composition
comprises leachable tin at a level of 0 ppm to 150 ppm upon
administration.
Description
BACKGROUND
[0001] Certain radiolabelled haloaromatic compounds have proven to
be useful in nuclear medicine.
SUMMARY
[0002] Applicants have discovered that a stannylated polymer,
comprising monomer of formula (I), below, if prepared according to
available methods (e.g., as described in U.S. Pat. No. 7,658,910 to
Duncan Hunter and Xizhen Zhu of the University of Western Ontario;
hereinafter the "University Patent"), is generally contaminated
with substantial levels (e.g., >150 ppm to >1,000 ppm) of
leachable tin-containing by-products. See Examples 7-9 herein.
##STR00002##
[0003] Upon treatment with iodide, such as radioisotopic iodide,
the contaminated polymer comprising monomer of formula (I),
prepared according to methods of the University Patent, can yield a
radiolabeled iobenguane, also known as meta-iodobenzylguanidine or
MIBG, with unacceptable levels of leachable tin-containing
by-products.
##STR00003##
[0004] Applicants have recognized this problem and, without being
bound by theory, have identified certain sources of the problem.
The present disclosure describes useful solutions that address such
sources, thereby providing new and desirable compositions and
technologies for the preparation and use of stannylated polymers
and/or radiolabeled haloaromatics such as MIBG.
[0005] For example, as described herein, Applicants have developed
improved methods of preparing the polymer comprising monomer of
formula (I), relative to the methods described in the University
Patent, that minimize starting levels of leachable tin-containing
by-products in the polymer comprising monomer of formula (I).
[0006] Also, Applicants have developed improved methods of
purifying the polymer comprising monomer of formula (I), relative
to the methods described in the University Patent, that minimize
levels of leachable tin-containing by-products in the purified
polymer comprising monomer of formula (I).
[0007] Additionally, Applicants discovered that the polymer
comprising monomer of formula (I) is surprisingly sensitive to
moisture, O.sub.2 and/or ambient and elevated temperature. In fact,
Applicants have found that the polymer gradually and continuously
degrades in the presence of moisture, O.sub.2 and/or at ambient and
elevated temperatures, thus generating increasing levels of
leachable tin-containing fragments. See Example 8 herein.
[0008] As described herein, Applicants have developed various
improved technologies including, for example, methods of storing
the polymer comprising monomer of formula (I) under inert gas, such
as nitrogen, optionally at reduced temperature (e.g., -20.degree.
C.), that minimize the formation and/or presence of leachable
tin-containing by-products in the purified polymer comprising
monomer of formula (I).
[0009] Accordingly, in some aspects, provided are preparations of a
polymer, the polymer comprising a monomer of formula (I):
##STR00004##
or a pharmaceutically acceptable salt thereof, wherein leachable
tin is present in the preparation at a level within a range of
about 0 ppm to about 150 ppm.
[0010] In some aspects, the present disclosure provides kits
comprising the disclosed preparation of the polymer comprising
monomer of formula (I).
[0011] In some aspects, the present disclosure provides
pharmaceutical compositions comprising MIBG, or a pharmaceutically
acceptable salt thereof, wherein the MIBG is formed by contacting
iodine or an iodide salt with a disclosed preparation of the
polymer comprising monomer of formula (I).
[0012] In some aspects, the present disclosure provides methods for
providing or preparing purified polymer compositions.
[0013] In some aspects, provided is a method for preparing
meta-iodobenzylguanidine (MIBG), or a pharmaceutically acceptable
salt thereof, comprising contacting an iodide salt with disclosed
polymer preparation as described herein.
[0014] The present disclosure provides, among other things, various
technologies for manufacturing, purification, storage and/or
analysis of preparations comprising polymers as described
herein.
[0015] In some embodiments, the present disclosure provides polymer
preparations, and technologies for providing them, that
reproducibly show one or more desirable attributes (e.g., reduced
level of one or more contaminants or undesirable structures) as
compared with preparations that can result from prior methodologies
such as those set forth in the University Patent.
[0016] In some embodiments, the present disclosure identifies a
source of a problem with one or more aspects of prior technologies
for synthesis, purification, and/or storage for relevant polymer
preparations and/or radiolabeled haloaromatics.
[0017] In some embodiments, the present disclosure provides
improvements to reaction steps and/or purification and storage
protocols used in one or more prior synthesis methodologies used to
make, purify and/or store preparations of a polymer comprising the
monomer of formula (I).
[0018] In some aspects, provided is a method, the method comprising
administering to a subject a pharmaceutical composition
comprising:
[0019] (a) meta-iodobenzylguanidine (MIBG):
##STR00005##
or a pharmaceutically acceptable salt thereof, wherein MIBG is
formed by contacting an iodide salt with a preparation of a polymer
comprising monomer of formula (I):
##STR00006##
or a pharmaceutically acceptable salt thereof, the preparation of
the polymer comprising monomer of formula (I) comprising leachable
tin at a level of 0 ppm to 150 ppm;
[0020] (b) a pharmaceutically acceptable carrier, adjuvant, or
vehicle.
[0021] In some embodiments of the method, the pharmaceutical
composition comprises leachable tin at a level of 0 ppm to 150 ppm
upon administration.
BRIEF DESCRIPTIONS OF THE DRAWING
[0022] FIG. 1 illustrates typical bimodal particle size
distributions for polymer comprising monomer of formula (I) made
according to methods described in U.S. Pat. No. 7,658,910. Particle
sizes were determined from known wet dispersion laser diffraction
methods. The mean size for the bimodal particle size distribution
was found to be 32.64 .mu.m.
[0023] FIG. 2 illustrates typical particle size distributions for
polymer comprising monomer of formula (I) made according to methods
described herein such as those of Examples 1-6. Particle sizes were
determined from known wet dispersion laser diffraction methods.
Mean test results of Dv10, Dv50 and Dv90 are presented in the table
below.
TABLE-US-00001 [0024] Volume Mean Diameter Weighted (VMD) Residual
Obscuration Replicate Dv10 (.mu.m) Dv50 (.mu.m) Dv90 (.mu.m)
(.mu.m) (%) (%) 1 15.350 86.736 174.910 91.930 0.33 11.14 2 18.830
78.235 154.065 83.541 0.29 11.47 3 16.861 88.760 183.930 123.024
0.38 11.58 Mean 17.0 84.6 171.0 99.5 N/A N/A % RSD 10.3% 6.6% 9.0%
N/A N/A N/A
DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS
Radiolabeled Haloaromatics
[0025] Certain radiolabelled haloaromatic compounds have proven to
be useful in nuclear medicine. For example, MIBG, can be
radiolabeled with iodine for use as a diagnostic or therapeutic
agent. In particular, radiolabeled MIBG is used in a scintigraphy
method called an MIBG scan. Different iodine radioisotopes are used
to label MIBG for different applications. For example, iodine-123
(e.g., AdreView.RTM. iobenguane I-123) is typically used for
imaging purposes (e.g., for cardiac or tumor imaging); iodine-131
(e.g., Azedra.RTM. iobenguane I-131), which is longer lived and
provides much higher radiation intensity, is generally used for
therapeutic applications (e.g., where tissue destruction is
desired, such as in the treatment of tumors), but can also be used
as an imaging agent. Iobenguane localizes to adrenergic tissue and
thus can be used, for example, to target tumors such as
pheochromocytomas, paragangliomas, neuroblastomas, and/or other
neuroendocrine tumors.
[0026] It is desirable to produce isotopically-labeled MIBG in high
yield relative to cold non-radioactive MIBG. Among other things, it
is appreciated that, upon treatment of a patient with an infusion
of MIBG, the presence of cold non-radioactive "carrier" MIBG
molecules may inhibit uptake of radiolabeled MIBG, resulting, for
example, in less tumor radiation and/or increased risk of
cardiovascular side effects. The administration of high
concentrations of radiolabeled MIBG relative to cold MIBG thus
provides at least two significant benefits: greater tumor uptake
and reduced pharmacological toxicity such as, for example, reduced
frequency or severity of side effects, such as hypertension, nausea
or vomiting, which can often occur during MIBG infusion.
[0027] Efforts to produce isotopically-labeled iobenguane in high
yield have led to the use of organotin precursors that are
sufficiently reactive to undergo facile exchange with radioiodide.
For example, U.S. Pat. No. 5,565,185 discloses a process for
radiolabelling MIBG by iododestannylation of a small-molecule
trialkylaryltin precursors of formula (II), shown below in Scheme
1. However, this process is impractical because tin-containing
by-products are formed that leach into solution with the
radiolabelled MIBG. These toxic tin-containing contaminants are
difficult to separate from the radiolabelled MIBG.
##STR00007##
[0028] Leachable organotin compounds are highly toxic.
Tributyltin-containing compounds (e.g., tributyl tin hydride or
tributyl oxide) were once widely used as marine anti-biofouling
agents to improve the efficiency of ocean-going ships, but concerns
over the toxicity of these compounds led to a worldwide ban by the
International Maritime Organization. Some reports describe negative
biological effects on marine life at concentrations as low as 1
nanogram per liter. See Gajda, M. and Jancso, A. (2010)
"Organotins, formation, use, speciation and toxicology" Metal Ions
in Life Sciences vol. 7, pp. 111-152 (Eds. A. Sigel, H. Sigel,
R.K.O. Sigel), RSC Publishing Thomas Graham Hause.
[0029] U.S. Pat. No. 7,658,910 describes a solution to this
problem, particularly a stannylated polymer comprising monomer of
formula (I), shown above, and a process for radiolabelling MIBG by
iododestannylation of MIBG from the polymer comprising monomer (I).
In principle, iododestannylation of the polymeric precursor
comprising monomer (I) sheds radiolabeled MIBG into solution,
whereas the toxic tin-containing by-products remain bound to the
insoluble polymer. The present disclosure encompasses the insight
that, in practice, leachable tin-containing side products are
co-produced with the polymer, and can remain at undesirable levels
in preparations of radiolabeled MIBG. The present invention
provides the insight that there is a need for improved preparations
of the stannylated polymer comprising monomer of formula (I), and
the MIBG therapeutic (e.g., radiolabeled MIBG, and particularly
MIBG labeled with radioactive iodine such as 1-123 or, in
particular embodiments, I-131), that are substantially contaminant
free.
Polymer Preparations
[0030] As discussed, Applicants discovered that preparations of
polymers comprising monomer of formula (I) manufactured according
to prior technologies including, for example, those described in
the University Patent, are generally contaminated with unacceptable
levels of leachable tin and, furthermore, that such levels
typically increase with time. As described herein, Applicants have
modified certain of the reactions described in the University
Patent, and furthermore have developed purification protocols and
storage conditions that effectively reduce the levels of leachable
tin in preparations of polymers comprising monomers of formula (I),
and effectively reduce the levels of leachable tin in the resulting
MIBG therapeutic and pharmaceutical compositions comprising the
same.
[0031] In some aspects, provided are preparations of polymers
comprising monomer of formula (I):
##STR00008##
or pharmaceutically acceptable salts thereof
[0032] As used herein, the term "pharmaceutically acceptable salt"
refers to those salts which are, within the scope of sound medical
judgment, suitable for use in contact with the tissues of humans
and lower animals without undue toxicity, irritation, allergic
response and the like, and are commensurate with a reasonable
benefit/risk ratio. Pharmaceutically acceptable salts are well
known in the art. For example, S. M. Berge et al., describe
pharmaceutically acceptable salts in detail in J. Pharmaceutical
Sciences, 1977, 66, 1-19, incorporated herein by reference.
Pharmaceutically acceptable salts of the compounds of this
invention include those derived from suitable inorganic and organic
acids and bases. Examples of pharmaceutically acceptable, nontoxic
acid addition salts are salts of an amino group formed with
inorganic acids such as hydrochloric acid, hydrobromic acid,
phosphoric acid, sulfuric acid and perchloric acid or with organic
acids such as acetic acid, oxalic acid, maleic acid, tartaric acid,
citric acid, succinic acid or malonic acid or by using other
methods used in the art such as ion exchange. Other
pharmaceutically acceptable salts include adipate, alginate,
ascorbate, aspartate, benzenesulfonate, benzoate, bisulfate,
borate, butyrate, camphorate, camphorsulfonate, citrate,
cyclopentanepropionate, digluconate, dodecylsulfate,
ethanesulfonate, formate, fumarate, glucoheptonate,
glycerophosphate, gluconate, hemisulfate, heptanoate, hexanoate,
hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate, lactate,
laurate, lauryl sulfate, malate, maleate, malonate,
methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate,
oleate, oxalate, palmitate, pamoate, pectinate, persulfate,
3-phenylpropionate, phosphate, pivalate, propionate, stearate,
succinate, sulfate, tartrate, thiocyanate, p-toluenesulfonate,
undecanoate, valerate salts, and the like.
[0033] In some embodiments, preparations of polymer as described
herein include one or more monomers in a salt form and, in
particular, in a pharmaceutically acceptable salt form (e.g.,
comprising a pharmaceutically acceptable salt of an amino group).
In some embodiments, a pharmaceutically acceptable salt is a
hydrochloric acid (HCl) salt, yielding polymer comprising monomer
of formula (Ia). In some embodiments, a pharmaceutically acceptable
salt is an acetic acid (HOAc) salt, yielding polymer comprising
monomer of formula (Ib).
##STR00009##
[0034] In some embodiments, polymers as described herein comprise,
at least in part, homopolymeric segments as set forth in formula
(III):
##STR00010##
wherein n is 2 to 1,000,000. In some embodiments, n is 100 to
100,000. In some embodiments, n is 500 to 100,000. In some
embodiments, n is 500 to 50,000. In some embodiments, n is 500 to
10,000. In some embodiments, n is 500 to 1,000. In some
embodiments, n is 100 to 500. In some embodiments, n is 2 to 100.
In some embodiments, the polymer is crosslinked.
[0035] Reduced Levels of Leachable Tin
[0036] Technologies provided herein permit preparation and/or
maintenance of polymer preparations having low levels of leachable
tin. In some embodiments, provided polymer preparations have
reduced levels of leachable tin as compared with compositions
reliably obtained using prior technologies including, for example,
as set forth in the University Patent.
[0037] As used herein, the terms "leachable tin," "leachable
tin-containing side products" and "tin-containing fragments" are
used interchangeably and refer to tin salts or tin-containing
compounds that are soluble in, or miscible with, water (e.g.,
aqueous solutions) or organic solvents (e.g., methanol, ethanol,
diethyl ether, tetrahydrofuran, dichloromethane, hexane, acetone,
toluene, or acetonitrile). For example, the leachable tin
components referred to herein may include tin-containing fragments
from the polymer comprising monomer of formula (I) that wash from
the polymer upon treatment or washing with water and/or organic
solvents. In some embodiments of the polymer comprising monomer of
formula (I), the leachable tin-containing side products have a
molecular weight of less than 2,000 Daltons. In some embodiments,
the leachable tin-containing side products have a molecular weight
less than 1,000 Daltons. In some embodiments, the leachable
tin-containing side products have a molecular weight less than 500
Daltons. In some embodiments, at least some of the leachable
tin-containing side products include a di-butyl-tin-containing
substituent.
[0038] In some embodiments, provided polymer preparations have
leachable tin at a level within a range of about 0 ppm to about 850
ppm. In some embodiments, provided polymer preparations have
leachable tin at a level below about 850 ppm. In some embodiments,
provided polymer preparations have leachable tin at a level below
about 800 ppm. In some embodiments, provided polymer preparations
have leachable tin at a level below about 750 ppm. In some
embodiments, provided polymer preparations have leachable tin at a
level below about 700 ppm. In some embodiments, provided polymer
preparations have leachable tin at a level below about 650 ppm. In
some embodiments, provided polymer preparations have leachable tin
at a level below about 600 ppm. In some embodiments, provided
polymer preparations have leachable tin at a level below about 550
ppm. In some embodiments, provided polymer preparations have
leachable tin at a level below about 500 ppm. In some embodiments,
provided polymer preparations have leachable tin at a level below
about 450 ppm. In some embodiments, provided polymer preparations
have leachable tin at a level below about 400 ppm. In some
embodiments, provided polymer preparations have leachable tin at a
level below about 350 ppm. In some embodiments, provided polymer
preparations have leachable tin at a level below about 300 ppm. In
some embodiments, provided polymer preparations have leachable tin
at a level below about 250 ppm. In some embodiments, provided
polymer preparations have leachable tin at a level below about 200
ppm. In some embodiments, provided polymer preparations have
leachable tin at a level below about 150 ppm. In some embodiments,
provided polymer preparations have leachable tin at a level within
a range of about 0 ppm to about 150 ppm. In some embodiments, the
preparation comprising the polymer comprising monomer of formula
(I) includes leachable tin at a level of 0 ppm to 140 ppm. In some
embodiments, the preparation includes leachable tin at a level of 0
ppm to 130 ppm. In some embodiments, the preparation includes
leachable tin at a level of 0 ppm to 120 ppm. In some embodiments,
the preparation includes leachable tin at a level of 0 ppm to 110
ppm. In some embodiments, the preparation includes leachable tin at
a level of 0 ppm to 100 ppm. In some embodiments, the preparation
includes leachable tin at a level of 0 ppm to 90 ppm. In some
embodiments, the preparation includes leachable tin at a level of 0
ppm to 80 ppm. In some embodiments, the preparation includes
leachable tin at a level of 0 ppm to 70 ppm. In some embodiments,
the preparation includes leachable tin at a level of 0 ppm to 60
ppm. In some embodiments, the preparation includes leachable tin at
a level of 0 ppm to 50 ppm. In some embodiments, the preparation
includes leachable tin at a level of 0 ppm to 40 ppm. In some
embodiments, the preparation includes leachable tin at a level of 0
ppm to 30 ppm. In some embodiments, the preparation includes
leachable tin at a level of 0 ppm to 20 ppm. In some embodiments,
the preparation includes leachable tin at a level of 0 ppm to 10
ppm.
[0039] Applicants have discovered that levels of leachable tin in
the polymers comprising a monomer of formula (I) can increase with
time and/or upon exposure to one or more of moisture, temperature
and O.sub.2. In some embodiments, provided polymer preparations as
described herein with reduced levels of leachable tin maintain
their reduced levels of leachable tin for extended periods of time
under appropriate storage conditions. In some embodiments, provided
polymer preparations as described herein are subject to levels of
leachable tin that increase with time, but significantly less so
and/or at a lower rate, than known polymer preparations (e.g.,
those of U.S. Pat. No. 7,658,910) produce levels of leachable tin
with time.
[0040] In some particular embodiments, provided polymer
preparations maintain a reduced level of tin when stored at
-20.degree. C.; in some such embodiments, the reduced level of tin
is a level of less than about 850 ppm, less than about 800 ppm,
less than about 750 ppm, less than about 700 ppm, less than about
650 ppm, less than about 600 ppm, less than about 550 ppm, less
than about 500 ppm, less than about 450 ppm, less than about 400
ppm, less than about 350 ppm, less than about 300 ppm, less than
about 250 ppm, less than about 200 ppm, less than about 150 ppm,
less than about 100 ppm, less than about 90 ppm, less than about 80
ppm, less than about 70 ppm, less than about 60 ppm, less than
about 50 ppm, less than about 40 ppm, less than about 30 ppm, less
than about 20 ppm, and/or less than about 10 ppm for a period of
time that is at least 6 months, at least 1 year, at least 2 years,
at least 3 years, or more.
[0041] In some embodiments, provided polymer preparations have
leachable tin at a level below about 850 ppm, 800 ppm, 750 ppm, 700
ppm, 650 ppm, 600 ppm, 550 ppm, 500 ppm, 450 ppm, 400 ppm, 350 ppm,
300 ppm, 250 ppm, 200 ppm, 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110
ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30
ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 6 months at about
40.degree. C., 20.degree. C., 0.degree. C., -10.degree. C. or
-20.degree. C. In some embodiments, the provided polymer
preparations are stored about 1 month to about 6 months, or about 6
months, at any one or between any two of the above-indicated
temperatures under an inert gas such as N.sub.2. In some
embodiments, the provided polymer preparations are stored about 1
month to about 6 months, or about 6 months, at any one or between
any two of the above-indicated temperatures under air having a
relative humidity of 1% to 25%, 25% to 50%, 50% to 75%, 75% to 90%,
or higher. In some embodiments, the provided polymer preparations
are stored about 1 month to about 6 months, or about 6 months, at
any one or between any two of the above-indicated temperatures
under air having a relative humidity of about 60%. In some
embodiments, the provided polymer preparations are stored about 1
month to about 6 months, or about 6 months, at any one or between
any two of the above-indicated temperatures under air having a
relative humidity of about 75%.
[0042] In some embodiments, provided polymer preparations have
leachable tin at a level below about 850 ppm, 800 ppm, 750 ppm, 700
ppm, 650 ppm, 600 ppm, 550 ppm, 500 ppm, 450 ppm, 400 ppm, 350 ppm,
300 ppm, 250 ppm, 200 ppm, 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110
ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30
ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 1 year at about
40.degree. C., 20.degree. C., 0.degree. C., -10.degree. C. or
-20.degree. C. In some embodiments, the provided polymer
preparations are stored about 6 months to about 1 year, or about 1
year, at any one or between any two of the above-indicated
temperatures under an inert gas such as N.sub.2. In some
embodiments, the provided polymer preparations are stored about 6
months to about 1 year, or about 1 year, at any one or between any
two of the above-indicated temperatures under air having a relative
humidity of 1% to 25%, 25% to 50%, 50% to 75%, 75% to 90%, or
higher. In some embodiments, the provided polymer preparations are
stored about 6 months to about 1 year, or about 1 year, at any one
or between any two of the above-indicated temperatures under air
having a relative humidity of about 60%. In some embodiments, the
provided polymer preparations are stored about 6 months to about 1
year, or about 1 year, at any one or between any two of the
above-indicated temperatures under air having a relative humidity
of about 75%.
[0043] In some embodiments, provided polymer preparations have
leachable tin at a level below about 850 ppm, 800 ppm, 750 ppm, 700
ppm, 650 ppm, 600 ppm, 550 ppm, 500 ppm, 450 ppm, 400 ppm, 350 ppm,
300 ppm, 250 ppm, 200 ppm, 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110
ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30
ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 2 years at about
40.degree. C., 20.degree. C., 0.degree. C., -10.degree. C. or
-20.degree. C. In some embodiments, the provided polymer
preparations are stored about 1 year to about 2 years, or about 2
years, at any one or between any two of the above-indicated
temperatures under an inert gas such as N.sub.2. In some
embodiments, the provided polymer preparations are stored about 1
year to about 2 years, or about 2 years, at any one or between any
two of the above-indicated temperatures under air having a relative
humidity of 1% to 25%, 25% to 50%, 50% to 75%, 75% to 90%, or
higher. In some embodiments, the provided polymer preparations are
stored about 1 year to about 2 years, or about 2 years, at any one
or between any two of the above-indicated temperatures under air
having a relative humidity of about 60%. In some embodiments, the
provided polymer preparations are stored about 1 year to about 2
years, or about 2 years, at any one or between any two of the
above-indicated temperatures under air having a relative humidity
of about 75%.
[0044] In some embodiments, provided polymer preparations have
leachable tin at a level below about 850 ppm, 800 ppm, 750 ppm, 700
ppm, 650 ppm, 600 ppm, 550 ppm, 500 ppm, 450 ppm, 400 ppm, 350 ppm,
300 ppm, 250 ppm, 200 ppm, 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110
ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30
ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 3 years at about
40.degree. C., 20.degree. C., 0.degree. C., -10.degree. C. or
-20.degree. C. In some embodiments, the provided polymer
preparations are stored about 2 years to about 3 years, or about 3
years, at any one or between any two of the above-indicated
temperatures under an inert gas such as N.sub.2. In some
embodiments, the provided polymer preparations are stored about 2
years to about 3 years, or about 3 years, at any one or between any
two of the above-indicated temperatures under air having a relative
humidity of 1% to 25%, 25% to 50%, 50% to 75%, 75% to 90%, or
higher. In some embodiments, the provided polymer preparations are
stored about 2 years to about 3 years, or about 3 years, at any one
or between any two of the above-indicated temperatures under air
having a relative humidity of about 60%. In some embodiments, the
provided polymer preparations are stored about 2 years to about 3
years, or about 3 years, at any one or between any two of the
above-indicated temperatures under air having a relative humidity
of about 75%.
[0045] Inert Atmosphere
[0046] Applicants have found that exposure of a polymer comprising
monomer of formula (I), and/or of tin-containing synthetic
precursors thereof, to air and/or O.sub.2 can degrade
tin-containing fragments from the polymer and increase levels of
leachable tin in polymer preparations. This finding embodies the
identification of the source of a problem with certain prior
preparation technologies.
[0047] In light of this finding, Applicants have recognized that
maintaining polymer preparations as described herein under inert
atmospheric conditions can provide certain desirable and beneficial
advantages. Accordingly, in some embodiments, the present
disclosure provides polymer preparations maintained under inert gas
(e.g., enclosed in a container under inert gas). In some
embodiments the inert gas is nitrogen. In some embodiments the
inert gas is argon.
[0048] Reduced Moisture
[0049] Applicants have further discovered that exposure of a
polymer comprising monomer of formula (I), and/or of tin-containing
synthetic precursors thereof, to moisture can degrade
tin-containing fragments from the polymer and increase levels of
leachable tin in polymer preparations. Accordingly, in some
embodiments, the present disclosure provides polymer preparations
containing less than 2.0 wt % water, e.g., relative to the wt % of
polymer in the preparation. In some embodiments, the present
disclosure provides polymer preparations containing less than 1.5
wt % water, less than about 1.4 wt % water, less than about 1.3 wt
% water, less than about 1.2 wt % water, less than about 1.1 wt %
water, less than about 1.0 wt % water, less than about 0.9 wt %
water, less than about 0.8 wt % water, less than about 0.7 wt %
water, less than about 0.6 wt % water, less than about 0.5 wt %
water, less than about 0.4 wt % water, less than about 0.3 wt %
water, less than about 0.2 wt % water, or less than about 0.1 wt %
water, or less than about 0.05 wt % water, e.g., relative to the wt
% of polymer in the preparation.
[0050] Solvent-Free
[0051] Applicants have also discovered that exposure of the polymer
comprising monomer of formula (I), and tin-containing synthetic
precursors thereof, to organic solvents (e.g., methanol, ethanol,
diethyl ether, tetrahydrofuran, dichloromethane, hexane, acetone,
toluene, or acetonitrile) can degrade tin-containing fragments from
the polymer and increase the levels of leachable tin. In some
embodiments, the preparation comprising the polymer comprising
monomer of formula (I) contain less than about 0.5 wt % organic
solvents, e.g., relative to the wt % of polymer in the preparation.
In some embodiments, the preparation comprises less than about 0.4
wt % organic solvents, less than about 0.3 wt % organic solvents,
less than about 0.2 wt % organic solvents, or less than about 0.1
wt % organic solvents, e.g., relative to the wt % of polymer in the
preparation.
[0052] Pure and/or Stable Polymers
[0053] The insights and technologies provided in the present
disclosure permit production and/or maintenance of, and thus
provide, substantially pure polymer preparations.
[0054] For example, in some embodiments, the present invention
provides substantially pure preparations of polymers comprising
monomers of formula (I), or salts thereof. In some embodiments, a
pure preparation is characterized in that at least 90 wt % of the
monomers in the preparation have the structure of formula (I), or a
salt thereof. In some embodiments, at least 95 wt %, at least 96 wt
%. at least 97 wt %, at least 98 wt %, at least 99 wt %, at least
99.5 wt % or more of the monomers in the preparation have the
structure of formula (I), or a salt thereof
[0055] In some embodiments, the present disclosure provides pure
polymer preparations that are stable for extended periods of time
in that the percentage of monomers having the structure of formula
(I), or salts thereof, remains above a designated level as set
forth above, over a designated period of time under selected
conditions.
[0056] In some embodiments, the preparation comprises at least 95
wt % of the polymer comprising monomer of formula (I), or salt
thereof, for at least 6 months at -20.degree. C. In some
embodiments, the preparation comprises at least 95 wt % of the
polymer comprising monomer of formula (I), or salt thereof, for at
least 1 year at -20.degree. C. In some embodiments, the preparation
comprises at least 95 wt % of the polymer comprising monomer of
formula (I), or salt thereof, for at least 2 years at -20.degree.
C. In some embodiments, the preparation comprises at least 95 wt %
of the polymer comprising monomer of formula (I), or salt thereof,
for at least 3 years at -20.degree. C.
[0057] In other related embodiments, the preparation comprises at
least 98 wt % of the polymer comprising monomer of formula (I), or
salt thereof, for at least 6 months at -20.degree. C. In some
embodiments, the preparation comprises at least 98 wt % of the
polymer comprising monomer of formula (I), or salt thereof, for at
least 1 year at -20.degree. C. In some embodiments, the preparation
comprises at least 98 wt % of the polymer comprising monomer of
formula (I), or salt thereof, for at least 2 years at -20.degree.
C. In some embodiments, the preparation comprises at least 98 wt %
of the polymer comprising monomer of formula (I), or salt thereof,
for at least 3 years at -20.degree. C.
[0058] In some embodiments, polymer preparations (e.g., pure
polymer preparations) as provided herein are substantially free of
unintended side-product polymers comprising monomers formula (I).
In some specific embodiments, such provided polymer preparations
are substantially free of monomers of formulae (IV) and/or (V):
##STR00011##
or pharmaceutically acceptable salts thereof, and/or of polymers
that comprise them.
[0059] In some embodiments, provided polymer preparations contain
less than about a maximum level of monomers of formula (IV),
monomers of formula (V), or both, or pharmaceutically acceptable
salts thereof. In some embodiments, the maximum level is about 0.5
wt %. That is, in some embodiments, the present invention provides
polymer preparations in which monomers having the structure of
formula (IV), or pharmaceutically acceptable salts thereof, are
present at a level below about 0.5 wt %, relative to the wt % of
the monomers having the structure of formula (I) in the polymer. In
some embodiments, the present invention provides polymer
preparations in which monomers having the structure of formula (V),
or pharmaceutically acceptable salts thereof, are present at a
level below about 0.5 wt %, relative to the wt % of the monomers
having the structure of formula (I) in the polymer. In some
embodiments, the present invention provides polymer preparations in
which monomers having the structure of formula (IV) or formula (V),
or pharmaceutically acceptable salts thereof, are present at a
level below about 0.5 wt %, relative to the wt % of the monomers
having the structure of formula (I) in the polymer. In some
embodiments, the maximum level is about 0.4%, 0.3%, 0.2%, 0.1%, or
less.
[0060] In some embodiments, the present invention provides polymer
preparations comprising monomers of formula (I), wherein at least
90%, 95%, 96%, 97%, 98%, or 99% or more of the monomers in the
polymer are of formula (I). In some embodiments, the present
invention provides polymer preparations comprising monomers of
formula (I), wherein not more than 0.5%, 0.4%, 0.3%, 0.2%, 0.1%, or
less of the monomers in the polymer are of formula (IV) or formula
(V).
Kits
[0061] As described herein, Applicants have found that exposure of
polymers comprising monomers of formula (I), and/or tin-containing
synthetic precursors thereof, to air, O.sub.2, moisture, organic
solvents and/or ambient or increased temperature can degrade
tin-containing fragments from the polymer and increase levels of
leachable tin in polymer preparations. Among other things,
Applicants have developed strategies for maintaining polymer
preparations under conditions that minimize such degradation.
[0062] For example, in some embodiments, the present invention
provides technologies for storing polymer preparations under inert
gas for part or all of the time from its production until it is
used to prepare and/or converted into MIBG. Thus, in some
embodiments, the present invention provides preparations of
polymers comprising monomers having the structure of formula
(I):
##STR00012##
or a pharmaceutically acceptable salt thereof, wherein polymers in
the preparations include n monomers, the preparations having a
reduced level of leachable tin, which reduced level is between
about 0 ppm to about 150 ppm, the preparations being provided in a
kit that further comprises one or more containers that store the
polymer preparations under inert gas.
[0063] In some embodiments, provided kits may comprise any of the
polymer preparations as described herein.
[0064] In some embodiments, the pharmaceutically acceptable salt is
a hydrochloric acid (HCl) salt. In other embodiments, the
pharmaceutically acceptable salt is an acetic acid (HOAc) salt.
[0065] In some embodiments, containers included in provided kits
store polymer preparations under nitrogen. In some embodiments,
containers included in provided kits store polymer preparations
under argon.
[0066] In some embodiments, containers included in provided kits
are glass vials. In some embodiments, the glass vials are made from
Type I borosilicate glass or Type III soda lime glass. In some
embodiments, the glass vials are colored, such as green or amber.
In some embodiments, the glass vials have a volume of about 0.1
mL-1.0 mL, 1.0 mL-2.0 mL, 2.0 mL-5.0 mL, 5.0 mL-10.0 mL, 10.0
mL-20.0 mL, 20.0 mL-30.0 mL, 20.0 mL-40.0 mL, 40.0 mL-50.0 mL, or
greater. In some embodiments, the glass vials have a volume of
about 2.0 mL. In some embodiments, the glass vials have a height of
about 10-50 mm. In some embodiments, the glass vials have a height
of about 30-40 mm. In some embodiments, the glass vials may have a
height of about 35 mm. In some embodiments, the glass vials have an
inner diameter of about 5-10 mm. In some embodiments, the glass
vials have an inner diameter of about 7-8 mm. In some embodiments,
the glass vials have an outer diameter of about 5-25 mm. In some
embodiments, the glass vials have an outer diameter of about 10-20
mm. In some embodiments, the glass vials have an outer diameter of
about 12-13 mm. In some embodiments, the glass vials have an outer
diameter of about 16 mm.
[0067] In some embodiments, containers included in provided kits
are glass vials having a polymeric or rubber (e.g., synthetic
rubber) stopper or closure that seals the vial and substantially
prevents an escape of inert gas, such as nitrogen, from within the
sealed vial. In some embodiments, the polymeric stopper is made
from synthetic rubber. In some embodiments, the polymeric stopper
is made from bromobutyl polymer. In some embodiments, the polymeric
stopper, such as a bromobutyl stopper, is coated with a fluorinated
polymer coating, that may be applied to the stopper, for example,
via spray-dry coating process, to render the coated stopper
substantially chemically inert.
[0068] In some embodiments, the container, such as a glass vial,
included in provided kit, is sealed with a rubber septum that
substantially prevents an escape of inert gas, such as nitrogen,
from within the sealed vial. In some embodiments, containers
included in provided kits are amber glass vials made from Type I
borosilicate glass, having a volume of about 2.0 mL, a height of
about 35 mm, and outer diameter between about 12-16 mm. In some
embodiments, the above-described amber glass vials are sealed with
a polymeric stopper made from bromobutyl polymer, where the stopper
is coated with a fluorinated polymer coating, the coating having a
thickness of about 10 .mu.m to about 20 .mu.m. In some embodiments,
the rubber septum is fastened to the glass vial via and aluminum
seal.
[0069] In some embodiments, provided kits, and/or containers
included therein, include a means, such as dry ice, or a
refrigeration unit, to cool the kit below ambient temperature
(e.g., 20.degree. C., 0.degree. C., -10.degree. C. or -20.degree.
C.).
[0070] In some embodiments, provided kits comprise instructions for
use.
[0071] In some embodiments, provided kits permit storage of polymer
preparations as described herein over extended periods of time
while preserving their stability (e.g., with respect to level of
leachable tin levels and/or with respect to unintended
side-products e.g., as described herein). In some embodiments,
stability is preserved at -20.degree. C. for a period of time that
is at least 6 months, at least 1 year at least 2 years, at least 3
years, or more.
[0072] In some embodiments, provided kits preserve stability with
respect to minimum percentage of monomers having the structure of
formula (I), or a pharmaceutically acceptable salt thereof, in a
polymer preparation. In some embodiments, such percentage is at
least 96%, 96%, 97%, 98%, 99%, 99.5%, or more.
[0073] In some embodiments, provided kits preserve stability with
respect to maximal level of one or more unintended side products.
For example, in some embodiments, provided kits preserve stability
with respect to maximum percentage of monomers having the structure
of formula (IV), or pharmaceutically acceptable salts thereof
and/or to maximum percentage of monomers having the structure of
formula (V), or pharmaceutically acceptable salts thereof, or both.
In some embodiments, such maximal percentage is less than about
0.5%, less than about 0.4%, less than about 0.3%, less than about
0.2%, less than about 0.1%, or less.
[0074] In some embodiments, provided kits preserve stability with
respect to maximal level of leachable tin content. In some
embodiments, such maximum level is less than about 150 ppm less
than about 100 ppm, less than about 50 ppm less than about 25 ppm,
or less.
[0075] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 150 ppm, 140 ppm, 130 ppm, 120
ppm, 110 ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40
ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 6 months at
-20.degree. C.
[0076] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 20 ppm for at least 6 months
at -20.degree. C.
[0077] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 150 ppm, 140 ppm, 130 ppm, 120
ppm, 110 ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40
ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 9 months at
-20.degree. C.
[0078] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 20 ppm for at least 9 months
at -20.degree. C.
[0079] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 150 ppm, 140 ppm, 130 ppm, 120
ppm, 110 ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40
ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 1 year at
-20.degree. C.
[0080] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 20 ppm for at least 1 year at
-20.degree. C.
[0081] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 150 ppm, 140 ppm, 130 ppm, 120
ppm, 110 ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40
ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 2 years at
-20.degree. C.
[0082] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 20 ppm for at least 2 years at
-20.degree. C.
[0083] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 150 ppm, 140 ppm, 130 ppm, 120
ppm, 110 ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40
ppm, 30 ppm, 20 ppm, 10 ppm, 5 ppm or less for at least 3 years at
-20.degree. C.
[0084] In some embodiments of the kit, polymer preparations have
leachable tin at a level below about 20 ppm for at least 3 years at
-20.degree. C.
[0085] In some embodiments of the kit, the polymer preparations
contain water at a level of less than 2.0 wt % water, e.g.,
relative to the wt % of polymer in the preparation. In some
embodiments of the kit, the polymer preparations contain less than
1.5 wt % water, less than about 1.4 wt % water, less than about 1.3
wt % water, less than about 1.2 wt % water, less than about 1.1 wt
% water, less than about 1.0 wt % water, less than about 0.9 wt %
water, less than about 0.8 wt % water, less than about 0.7 wt %
water, less than about 0.6 wt % water, less than about 0.5 wt %
water, less than about 0.4 wt % water, less than about 0.3 wt %
water, less than about 0.2 wt % water, or less than about 0.1 wt %
water, or less than about 0.05 wt % water, e.g., relative to the wt
% of polymer in the preparation.
MIBG Compositions and Compositions Comprising a Compound of Formula
(VI)
[0086] Among other things, the present invention provides
technologies, for example utilizing polymer preparations as
described herein, for the production of MIBG compositions, and
compositions comprising a compound of formula (VI):
##STR00013##
or pharmaceutically acceptable salts thereof, wherein R.sub.1 is a
radioisotopic label.
[0087] As used herein, the term "radioisotopic label" of R.sub.1 is
intended to mean a radioisotope of an atom or ion that enables
detection of the compound or composition that includes the
radioisotopic label. The radioisotopic label, includes, but is not
limited to, a radiohalogen isotope (i.e., atom or ion) including
any one of fluoride (.sup.18F), bromide (.sup.74Br, .sup.75Br,
.sup.76Br, .sup.77Br, .sup.78Br, .sup.80Br, .sup.82Br, .sup.83Br,
.sup.84Br, .sup.85Br, .sup.86Br, .sup.87Br, .sup.88Br, .sup.89Br or
.sup.90Br), iodide (.sup.123I, .sup.124I, .sup.125I, .sup.131I) or
astatine (.sup.209At, .sup.210At or .sup.211At).
[0088] In some embodiments, R.sub.1 is .sup.18F.
[0089] In some embodiments, R.sub.1 is .sup.74Br, .sup.75Br,
.sup.76Br, .sup.77Br, .sup.78Br, .sup.80Br, .sup.82Br, .sup.83Br,
.sup.84Br, .sup.85Br, .sup.86Br, .sup.87Br, .sup.88Br, .sup.89Br or
.sup.90Br.
[0090] In some embodiments, R.sub.1 is .sup.123I, .sup.124I,
.sup.125, .sup.131I. In some embodiments, R.sub.1 is .sup.123I. In
some embodiments, R.sub.1 is .sup.124I. In some embodiments,
R.sub.1 is .sup.125I. In some embodiments, R.sub.1 is .sup.131I. In
some embodiments, R.sub.1 is .sup.123I. In some embodiments,
R.sub.1 is .sup.131I.
[0091] In some embodiments, R.sub.1 is .sup.209At, .sup.210At or
.sup.211At. In some embodiments, R.sub.1 is .sup.209At. In some
embodiments, R.sub.1 is .sup.210At. In some embodiments, R.sub.1 is
.sup.211At.
[0092] According to some aspects, provided are pharmaceutical
compositions comprising MIBG, or the compound of formula (VI), or a
pharmaceutically acceptable salt thereof, and a pharmaceutically
acceptable carrier, adjuvant, or vehicle, wherein the MIBG is
formed by contacting iodine or an iodide salt with a polymer
preparation as described herein i.e., of polymers comprising
monomers of formula (I):
##STR00014##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the polymer preparation comprises leachable tin at a level of 0 ppm
to 150 ppm.
[0093] In some embodiments, the polymer preparation has leachable
tin at a level below about 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110
ppm, 100 ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30
ppm, 20 ppm, 10 ppm or 5 ppm.
[0094] According to further aspects, provided is a pharmaceutical
composition comprising the compound of formula (VI):
##STR00015##
or a pharmaceutically acceptable salt thereof, and a
pharmaceutically acceptable carrier, adjuvant, or vehicle, wherein
R.sub.1 is a radioisotopic label, and the pharmaceutical
composition comprises leachable tin at a level of 0 ppm to 150
ppm.
[0095] In some embodiments, provided is a pharmaceutical
composition comprising meta-iodobenzylguanidine (MIBG):
##STR00016##
or a pharmaceutically acceptable salt thereof, and a
pharmaceutically acceptable carrier, adjuvant, or vehicle, wherein
the pharmaceutical composition comprises leachable tin at a level
of 0 ppm to 150 ppm.
[0096] In some embodiments, the pharmaceutical composition,
comprising MIBG, or the compound of formula (VI) or a
pharmaceutically acceptable salt thereof, has leachable tin at a
level below about 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110 ppm, 100
ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30 ppm, 20
ppm, 10 ppm or 5 ppm.
[0097] Described herein are methods for characterizing levels of
leachable tin in any of the polymer preparations disclosed herein,
and for characterizing levels of leachable tin in any of the
disclosed pharmaceutical compositions comprising the compound of
formula (VI) or MIBG. In some embodiments, such methods include the
use of inductively coupled plasma mass spectrometry (ICP-MS). Such
methods are described in greater detail in the Examples below.
Applicants note that methods for characterizing levels of leachable
tin in any of the disclosed pharmaceutical compositions may
conveniently be conducted upon compositions comprising
non-radioisotopic analogs of compounds of formula (VI) or MIBG. For
example, a polymer comprising monomers of formula (I) may be
contacted with non-radioisotopic iodine or iodide to form
non-radioisotopic MIBG, which can safely be subjected to analytical
methods such as ICP-MS to quantify levels of leachable tin in the
non-radioisotopic MIBG composition. Such levels can readily be
correlated to compositions comprising radioisotopic MIBG formed
from radioisotopic iodide.
[0098] In some embodiments, the compound of formula (VI) is formed
by contacting a radioisotope of a halogen ion with a polymer
preparation as described herein i.e., of polymers comprising
monomers of formula (I).
[0099] In certain embodiments of provided MIBG compositions, the
MIBG is formed by contacting the iodide salt with a polymer
preparation provided herein.
[0100] In certain embodiments of provided compositions comprising
the compound of formula (VI), the compound of formula (VI) is
formed by contacting a radioisotope of fluoride, bromide, iodide or
astatine with a polymer preparation provided herein.
[0101] In certain embodiments, provided MIBG compositions, or
compositions comprising the compound of formula (VI), are
formulated for administration to a patient in need thereof
[0102] In some embodiments of the pharmaceutical composition, the
iodide salt is sodium iodide. In other embodiments, the iodide salt
is sodium I-123 iodide. In some embodiments the iodide salt is
sodium I-131 iodide.
[0103] In some embodiments, provided MIBG compositions, or
compositions comprising the compound of formula (VI), are
formulated for intravenous administration to a patient.
[0104] In some embodiments, provided MIBG compositions, or
compositions comprising the compound of formula (VI), are
formulated as an Imaging Dose to provide 1-50 mCi/kg, 5-30 mCi/kg,
10-25 mCi/kg or about 3-6 mCi/kg of radioactivity (e.g., of 1-131
or At-211), for example, upon intravenous administration to a
patient in need thereof. In some embodiments, the Imaging Dose is
used, for example, to determine if a patient meets radiological
entry criteria and/or to establish dosimetry for the subject.
[0105] In some embodiments, provided MIBG compositions, or
compositions comprising the compound of formula (VI), are
formulated as an Therapeutic Dose to provide 50-1,000 mCi/kg,
100-800 mCi/kg, 400-600 mCi/kg or about 500 mCi of radioactivity
(e.g., of 1-131 or At-211), for example, upon intravenous
administration to a patient in need thereof. In some embodiments,
the Therapeutic Dose is followed by imaging of the patient within 7
days post infusion. In some embodiments, the Therapeutic Dose is
optionally adjusted equally if warrented by results of a dosimetry
evaluation. In some embodiments, the patient will receive a second
Therapeutic Dose of MIBG at least 2, 3, 4 or more months later.
[0106] The term "patient," as used herein, means an animal,
preferably a mammal, and most preferably a human. In some
embodiments, the patient is in need of treatment for malignant
pheochromocytoma, a rare, hard-to-access neuroendocrine tumor that
develops in the core of an adrenal gland. In some embodiments, the
patient is in need of treatment for neuroendocrine tumors (NETs),
rare tumors of the nervous and endocrine systems. In some
embodiments, the NET is neuroblastoma, the most common extracranial
solid cancer in childhood and the most common cancer in infancy. In
some embodiments, the patient is a child in need of treatment for
neuroblastoma. In other embodiments, the patient is an adult in
need of treatment for pheochromocytoma, a neuroendocrine tumor of
the medulla of the adrenal glands.
[0107] The term "pharmaceutically acceptable carrier, adjuvant, or
vehicle" refers to a non-toxic carrier, adjuvant, or vehicle that
does not destroy the pharmacological activity of the compound with
which it is formulated. Pharmaceutically acceptable carriers,
adjuvants or vehicles that may be used in the compositions of this
invention include, but are not limited to, ion exchangers, alumina,
aluminum stearate, lecithin, serum proteins, such as human serum
albumin, buffer substances such as phosphates, glycine, sorbic
acid, potassium sorbate, partial glyceride mixtures of saturated
vegetable fatty acids, water, salts or electrolytes, such as
protamine sulfate, disodium hydrogen phosphate, potassium hydrogen
phosphate, sodium chloride, zinc salts, colloidal silica, magnesium
trisilicate, polyvinyl pyrrolidone, cellulose-based substances,
polyethylene glycol, sodium carboxymethylcellulose, polyacrylates,
waxes, polyethylene-polyoxypropylene-block polymers, polyethylene
glycol and wool fat.
[0108] In some embodiments, the pharmaceutical composition
comprising MIBG, or a pharmaceutically acceptable salt thereof,
particularly an acetic acid (HOAc) salt thereof, formed by
contacting the iodide salt with any of the above disclosed
preparations of a polymer comprising monomer of formula (I), may be
administered orally, parenterally, by inhalation spray, topically,
rectally, nasally, buccally, vaginally or via an implanted
reservoir. The term "parenteral" as used herein includes
subcutaneous, intravenous, intramuscular, intra-articular,
intra-synovial, intrasternal, intrathecal, intrahepatic,
intralesional and intracranial injection or infusion techniques.
Preferably, the compositions are administered intravenously.
Sterile injectable forms of the compositions of this invention may
be aqueous or oleaginous suspension. These suspensions may be
formulated according to techniques known in the art using suitable
dispersing or wetting agents and suspending agents. The sterile
injectable preparation may also be a sterile injectable solution or
suspension in a non-toxic parenterally acceptable diluent or
solvent.
[0109] In some embodiments, the sterile injectable preparation
comprises MIBG at a concentration of 0.0001-0.1 mg/mL. In some
embodiments, the sterile injectable preparation comprises MIBG at a
concentration of 0.001-0.01 mg/mL. In some embodiments, the sterile
injectable preparation has a radiochemical purity >90% or
>95%. In some embodiments, the sterile injectable preparation
comprises gentisate, for example, at a concentration of 2-200 mg/mL
or 20-25 mg/mL. In some embodiments, the sterile injectable
preparation comprises ascorbate, for example, at a concentration of
2-200 mg/mL or 48-64 mg/mL. In some embodiments, the sterile
injectable preparation comprises gentisate. In some embodiments,
the sterile injectable preparation has a pH of 3-7. In some
embodiments, the sterile injectable preparation has a pH of 4-6. In
some embodiments, the sterile injectable preparation has a pH of
4.5-5.5.
[0110] In some embodiments, provided MIBG compositions (e.g.,
formed by contacting the iodide salt with a provided polymer
preparation), or compositions comprising the compound of formula
(VI), are substantially free of (e.g., comprise less than 2 wt %
of) meta-iodobenzylamine (MIBA), meta-iodobenzylbiguanidine
(MIBBG), and/or meta-hydroxybenzylguanidine (MHBG).
##STR00017##
[0111] In some embodiments, provided MIBG pharmaceutical
compositions, or pharmaceutical compositions comprising the
compound of formula (VI), contain less than about 1.0 wt % MIBA,
relative to the wt % of the MIBG. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.5 wt % MIBA. In
some embodiments, the composition comprising MIBG, or compositions
comprising the compound of formula (VI), contain less than about
0.4 wt % MIBA. In some embodiments, the composition comprising
MIBG, or compositions comprising the compound of formula (VI),
contain less than about 0.3 wt % MIBA. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.2 wt % MIBA. In
some embodiments, the composition comprising MIBG, or compositions
comprising the compound of formula (VI), contain less than about
0.1 wt % MIBA.
[0112] In some embodiments, the pharmaceutical composition
comprising MIBG, or pharmaceutical compositions comprising the
compound of formula (VI), contain less than about 1.0 wt % MIBBG,
relative to the wt % of the MIBG. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.5 wt % MIBBG.
In some embodiments, the composition comprising MIBG, or
compositions comprising the compound of formula (VI), contain less
than about 0.4 wt % MIBBG. In some embodiments, the composition
comprising MIBG, or compositions comprising the compound of formula
(VI), contain less than about 0.3 wt % MIBBG. In some embodiments,
the composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.2 wt % MIBBG.
In some embodiments, the composition comprising MIBG, or
compositions comprising the compound of formula (VI), contain less
than about 0.1 wt % MIBBG.
[0113] In some embodiments, the pharmaceutical composition
comprising MIBG, or pharmaceutical compositions comprising the
compound of formula (VI), contain less than about 1.0 wt % MHBG,
relative to the wt % of the MIBG. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.5 wt % MHBG. In
some embodiments, the composition comprising MIBG, or compositions
comprising the compound of formula (VI), contain less than about
0.4 wt % MHBG. In some embodiments, the composition comprising
MIBG, or compositions comprising the compound of formula (VI),
contain less than about 0.3 wt % MHBG. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.2 wt % MHBG. In
some embodiments, the composition comprising MIBG, or compositions
comprising the compound of formula (VI), contain less than about
0.1 wt % MHBG.
[0114] In some embodiments, the pharmaceutical composition
comprising MIBG, or pharmaceutical compositions comprising the
compound of formula (VI), contain less than about 1.0 wt % MIBA,
MIBBG and/or MHBG, relative to the wt % of the MIBG. In some
embodiments, the composition comprising MIBG, or compositions
comprising the compound of formula (VI), contain less than about
0.5 wt % MIBA, MIBBG and/or MHBG. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.4 wt % MIBA,
MIBBG and/or MHBG. In some embodiments, the composition comprising
MIBG, or compositions comprising the compound of formula (VI),
contain less than about 0.3 wt % MIBA, MIBBG and/or MHBG. In some
embodiments, the composition comprising MIBG, or compositions
comprising the compound of formula (VI), contain less than about
0.2 wt % MIBA, MIBBG and/or MHBG. In some embodiments, the
composition comprising MIBG, or compositions comprising the
compound of formula (VI), contain less than about 0.1 wt % MIBA,
MIBBG and/or MHBG.
Polymer Synthesis and Purification
[0115] In certain embodiments, polymer preparations provided in
accordance with the present invention are prepared according to
synthetic methods of Scheme 2 as set forth below:
##STR00018##
[0116] In some embodiments, provided polymer preparations are
prepared as follows. Di-n-butyltin dichloride starting material is
reduced using hydride. As described below in Examples 1a and 1b,
Applicants discovered that reduction via NaBH.sub.4 was quicker,
more robust and higher yielding than previously-described
reactions, which typically utilized LiAlH.sub.4. Reduction with
NaBH.sub.4 was safer and more amenable to scale-up. In some
embodiments, temperature is maintained between 0.degree. C. and
10.degree. C. Applicants found that the resulting di-n-butyltin
dihydride was easier to purify upon work-up from reduction with
NaBH.sub.4 than it was upon reduction with LiAlH.sub.4. Without
being bound by theory, it is believed that freshly prepared
di-n-butyltin dihydride, upon reduction with NaBH.sub.4, generates
cleaner tin-containing starting material and contributes,
ultimately, to a cleaner form of polymer with fewer leachable
tin-containing fragments. In some embodiments, aqueous work-up of
the reduction with NaBH.sub.4 is followed by a distillative
purification of the crude di-n-butyltin dihydride.
[0117] In some embodiments, 2,3-bromobenzylamine I-6 freebase is
then reacted with 1,2-bis(chlorodimethylsilyl)ethane I-5 in
dichloromethane with triethylamine at ambient temperature for at
least about 14 hours. In some embodiments, the resultant suspension
is filtered, the product containing filtrate concentrated and
triturated with hexane to precipitate by-products that are filtered
and concentrated to a crude oil. Purification via high vacuum
distillation gives the product I-8 as colorless oil.
[0118] In the following step, di-n-butyltin dihydride I-2 is
combined with di-n-butyltin dichloride I-1 in the presence of
silica purified divinyl benzene and AIBN at ambient temperature to
form the 3,4-(2-dibutylchlorostannyl ethyl) vinyl benzene monomer
I-4. This monomer undergoes suspension polymerization in aqueous
1-octanol at reflux with additional silica purified divinyl benzene
and AIBN to form polymer I-7, which is isolated by filtration and
washed with water, prior to centrifugal washing with one or more
solvents, including acetone, methanol, toluene and
tetrahydrofuran.
[0119] The next step involves an initial reaction of I-8 in
tetrahydrofuran at -65 to -80.degree. C. with 2.5M n-butyl lithium
in hexane. Polymer I-7 is then charged in a single portion and
reaction continues at -65 to -80.degree. C. for 12-18 hours. The
suspension is warmed to room temperature, quenched with methanol
and acid, such as 1M aqueous HCl, is used to adjust the pH to 4 to
5 for removal of the silyl protecting group. Following overnight
agitation at ambient temperature, polymer I-10 is then collected by
centrifugation and washed with methanol, methanol/water (1:1), and
finally methanol.
[0120] Next, polymer I-10 is coupled with cyanamide and
triethylamine in toluene at 54-56.degree. C. for about 24 to 26
hours to form the guanidinium chloride intermediate polymer (Ia).
This is isolated and washed centrifugally with acetonitrile,
methanol and acetonitrile again prior to drying in vacuo. An
acetate salt swap is then performed via multiple (e.g., 8)
centrifugal washes using 1.0M sodium acetate in 70:30
ethanol:purified water to form the guanidinium acetate polymer
(Ib).
[0121] The resultant acetate salt of the polymer comprising monomer
of formula (I) is subjected to a multi-step purification protocol.
First, the resulting polymer (Ib) acetic acid salt is washed with
95% aqueous ethanol (8.times.4.3 vol.) then isolated by filtration
under nitrogen using a Buchner flask and funnel. Polymer (Ib) is
dried in a vacuum at ambient temperature. Second, the vacuum is
stopped and the Buchner funnel, containing polymer (Ib), is charged
with nitrogen gas and absolute ethanol (4.times.4.30 vol). The
absolute ethanol washes under nitrogen further purify polymer (Ib)
and remove traces of water from the wet-cake. Third, polymer (Ib)
is subjected to a multi-stage drying process encompassing (i)
drying at ambient temperature and pressure with a flow of nitrogen,
(ii) drying at ambient temperature under vacuum with a flow of
nitrogen, and (iii) drying at 30.degree. C. to 40.degree. C. under
vacuum with a flow of nitrogen to drive off residual solvent.
Polymer (Ib) is sensitive to excessive heat but tolerates gently
heating of this multi-stage drying process. Finally, purified
polymer (Ib) is stored under an inert gas, such as nitrogen and, in
some instances, cooled to -20.degree. C. for storage until use.
[0122] In some embodiments, the present disclosure provides and/or
utilizes a multi-step purification protocol, including aqueous
ethanol washes, anhydrous ethanol washes, vacuum, heating and
storage under nitrogen gas at reduced pressure was found to greatly
improve the purity and stability of the polymer comprising monomer
of formula (I), such that leachable tin is minimized to a level of
0 ppm to 150 ppm.
[0123] According to some aspects, provided are methods for
preparing a purified composition of a polymer comprising monomer of
formula (I):
##STR00019##
or a pharmaceutically acceptable salt thereof, the method
comprising the steps of:
[0124] solvent-treating a preparation comprising the polymer or
pharmaceutically acceptable salt thereof, by contacting the
preparation with a solvent, and then removing substantially all of
the solvent so that a solvent-depleted material comprising the
polymer or pharmaceutically acceptable salt thereof is generated;
and [0125] subjecting the solvent-depleted material to vacuum, and
to a temperature within a range of about 30.degree. C. to about
50.degree. C., the subjecting being performed under conditions and
for a time sufficient so that not more than about 150 ppm of
leachable tin is present and, therefore, a purified composition of
the polymer, or pharmaceutically acceptable salt thereof, has been
produced.
[0126] In some embodiments, the preparation is heated under an
inert gas, such as argon or nitrogen. In some embodiments, the
solvent-depleted material is protected from moisture and/or O.sub.2
and stored at ambient or reduced temperature (e.g., below
10.degree. C., 0.degree. C., -10.degree. C., -20.degree. C., or
-30.degree. C.).
[0127] In some embodiments, the present invention utilizes a
solvent that is or comprises methanol, ethanol, diethyl ether,
tetrahydrofuran, dichloromethane, hexane, acetone, toluene,
acetonitrile, or combinations thereof. In some embodiments, the
present invention utilizes a solvent that is an alcohol, for
example, methanol or ethanol. In some embodiments, the present
invention utilizes a solvent that is or comprises ethanol.
[0128] Applicants have found it beneficial, in some instances, to
run multiple (e.g., 2-15) "wash cycles," where each wash cycle
includes the steps of solvent-treating a preparation comprising the
polymer or pharmaceutically acceptable salt thereof and removing
substantially all of the solvent. In some embodiments, 2-5 wash
cycles are used whereby the preparation is solvent-treated, and
then the solvent is substantially removed, 2-5 times. In some
embodiments, 5-10 cycles are used whereby the preparation is
solvent-treated, and then the solvent is substantially removed,
5-10 times. In some embodiments, 10-15, or more wash cycles are
used whereby the preparation is solvent-treated, and then the
solvent is substantially removed, 10-15 or more times. In some
embodiments, the preparation is further subjected to one cycle of
heat at 30.degree. C. to 50.degree. C. and/or vacuum. In some
embodiments, the preparation is further subjected to 1-10 cycles of
heat at 30.degree. C. to 50.degree. C. and/or vacuum.
[0129] Without being bound by theory, Applicants found that aqueous
solvents effectively removed salts and water-soluble contaminants
from the polymer comprising monomer of formula (I), whereas
anhydrous solvents, such as absolute ethanol, effectively removed
water from the polymer preparations. Applicants found it
beneficial, in some instances, to contact a preparation with an
aqueous solvent, remove the aqueous solvent, and further contact
the preparation with an anhydrous solvent, and likewise remove the
anhydrous solvent from the polymer. For example, in some
embodiments, the polymer or salt thereof, is contacted with aqueous
ethanol, the aqueous ethanol is substantially removed, the
preparation is further contacted with anhydrous ethanol, and the
anhydrous ethanol is likewise removed from the polymer.
[0130] In some embodiments, the step of solvent-treating the
preparation comprises first and second solvent-treating steps,
performed with first and second solvents, wherein the first solvent
is a water miscible solvent, such as methanol, ethanol, or diethyl
ether, and the second solvent is an anhydrous water miscible
solvent. In some embodiments, the first solvent is aqueous
methanol, ethanol, or diethyl ether, and the second solvent is
anhydrous methanol, ethanol, or diethyl ether.
[0131] Applicants developed polymer preparations, according to the
present methods, that generally contain lower levels of water than
polymer preparations prepared according to methods described in
U.S. Pat. No. 7,658,910. Without being bound by theory, it is
believed that reduced levels of water in the presently disclosed
polymer preparations contribute to the robust stability and low
levels of leachable tin-containing impurities, relative to those of
polymer preparations prepared according to methods described in
U.S. Pat. No. 7,658,910.
[0132] In some embodiments, the resulting polymer preparations
contain water at a level of less than 2.0 wt % water, e.g.,
relative to the wt % of polymer in the preparation. In some
embodiments, the polymer preparations contain less than 1.5 wt %
water, less than about 1.4 wt % water, less than about 1.3 wt %
water, less than about 1.2 wt % water, less than about 1.1 wt %
water, less than about 1.0 wt % water, less than about 0.9 wt %
water, less than about 0.8 wt % water, less than about 0.7 wt %
water, less than about 0.6 wt % water, less than about 0.5 wt %
water, less than about 0.4 wt % water, less than about 0.3 wt %
water, less than about 0.2 wt % water, or less than about 0.1 wt %
water, or less than about 0.05 wt % water, e.g., relative to the wt
% of polymer in the preparation.
[0133] In some embodiments, the preparation is heated at 25.degree.
C. to 80.degree. C. In other embodiments, the preparation is heated
at 30.degree. C. to 60.degree. C. In some embodiments, the
preparation is heated at 30.degree. C. to 50.degree. C. In some
embodiments, the preparation is heated at 30.degree. C. to
40.degree. C.
[0134] In some embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 5-60 minutes. In some
embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 1-4 hours. In some
embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 4-12 hours. In some
embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 12-24 hours. In some
embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 1-2 days. In some
embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 2-6 days. In some
embodiments, the preparation is heated at any of the
above-indicated temperature ranges for 1-2 weeks.
[0135] In some embodiments, the preparation is subjected to a
vacuum for 1-12 hours. In some embodiments, the preparation is
subjected to a vacuum for 12-24 hours. In some embodiments, the
preparation is subjected to a vacuum for 1-2 days. In some
embodiments, the preparation is subjected to a vacuum for 2-6 days.
In some embodiments, the preparation is subjected to a vacuum for
1-2 weeks.
[0136] According to some aspects, provided are methods for
preparing meta-iodobenzylguanidine (MIBG):
##STR00020##
or a pharmaceutically acceptable salt thereof, comprising
contacting an iodide salt with preparation comprising a polymer
comprising monomer of formula (I):
##STR00021##
or a pharmaceutically acceptable salt thereof, the preparation
comprising leachable tin at a level of 0 ppm to 150 ppm.
[0137] In some embodiments, the method comprises any one of the
preparations comprising the polymer comprising monomer of formula
(I) described above.
[0138] In some embodiments, the method yields MIBG, or a
pharmaceutical composition comprising MIBG, the pharmaceutical
composition comprising leachable tin at a level of 0 ppm to 150
ppm.
Methods of Administration
[0139] In some aspects, provided is a method, the method comprising
administering to a subject a pharmaceutical composition
comprising:
[0140] (a) meta-iodobenzylguanidine (MIBG):
##STR00022##
or a pharmaceutically acceptable salt thereof, wherein MIBG is
formed by contacting an iodide salt with a preparation of a polymer
comprising monomer of formula (I):
##STR00023##
or a pharmaceutically acceptable salt thereof, the preparation of
the polymer comprising monomer of formula (I) comprising leachable
tin at a level of 0 ppm to 150 ppm;
[0141] (b) a pharmaceutically acceptable carrier, adjuvant, or
vehicle.
[0142] According to further aspects, provided is a method, the
method comprising administering to a subject a pharmaceutical
composition comprising the compound of formula (VI):
##STR00024##
or a pharmaceutically acceptable salt thereof, and a
pharmaceutically acceptable carrier, adjuvant, or vehicle, wherein
R.sub.1 is a radioisotopic label, and the pharmaceutical
composition comprises leachable tin at a level of 0 ppm to 150
ppm.
[0143] In some embodiments, the method comprises administering to a
subject a pharmaceutical composition comprising
meta-iodobenzylguanidine (MIBG):
##STR00025##
or a pharmaceutically acceptable salt thereof, and a
pharmaceutically acceptable carrier, adjuvant, or vehicle, wherein
the pharmaceutical composition comprises leachable tin at a level
of 0 ppm to 150 ppm.
[0144] In some embodiments of the method, the pharmaceutical
composition, comprising MIBG, or the compound of formula (VI) or a
pharmaceutically acceptable salt thereof, has leachable tin at a
level below about 150 ppm, 140 ppm, 130 ppm, 120 ppm, 110 ppm, 100
ppm, 90 ppm, 80 ppm, 70 ppm, 60 ppm, 50 ppm, 40 ppm, 30 ppm, 20
ppm, 10 ppm or 5 ppm.
[0145] In some embodiments of the method, the pharmaceutical
composition has leachable tin at a level within a range of about 0
ppm to about 100 ppm upon administration. In some embodiments of
the method, the pharmaceutical composition has leachable tin at a
level within a range of about 0 ppm to about 75 ppm upon
administration. In some embodiments of the method, the
pharmaceutical composition has leachable tin at a level within a
range of about 0 ppm to about 50 ppm upon administration. In some
embodiments of the method, the pharmaceutical composition has
leachable tin at a level within a range of about 0 ppm to about 25
ppm upon administration. In some embodiments of the method, the
pharmaceutical composition has leachable tin at a level within a
range of about 0 ppm to about 10 ppm upon administration. As used
herein, the term "upon administration" refers to a period of time
at or just prior to administration, for example, on the day prior
to administration, on the same day as administration, within eight
hours of administration, with two hours of administration, within
one hour of administration, or at the same time as administration
to the subject.
[0146] In some embodiments of the method, the preparation of a
polymer is any of the preparations described herein.
[0147] In some embodiments of the method, the iodide salt is sodium
I-131 iodide.
[0148] In some embodiments of the method, the subject is in need of
imaging for one or more potential neuroendocrine tumors in the
subject. In some embodiments of the method, the subject is in need
of treatment for one or more neuroendocrine tumors in the subject.
In some embodiments of the method, the neuroendocrine tumors are
metastatic. In some embodiments of the method, at least one or more
neuroendocrine tumors are located within the adrenal glands of the
subject. In some embodiments of the method, the subject is in need
of treatment for one or more pheochromocytomas. In some embodiments
of the method, the subject is in need of treatment for one or more
paragangliomas, i.e., outside the adrenal glands of the subject. In
some embodiments of the method, the subject is in need of treatment
for one or more neuroblastomas.
EXEMPLIFICATION
[0149] The following Examples are offered as illustrative as a
partial scope and particular embodiments of the invention and are
not meant to be limiting of the scope of the invention.
Abbreviations and chemical symbols have their usual and customary
meanings unless otherwise indicated. Unless otherwise indicated,
the compounds described herein have been prepared, isolated and
characterized using the Schemes and other methods disclosed herein
or may be prepared using the same or similar procedures.
##STR00026##
Example 1a
Synthesis of Di-n-Butyltin Dihydride 1-2, Via LiAlH.sub.4
[0150] Di-n-butyltin dichloride (25.0 g, 1.0 eq) was dissolved in
diethyl ether (1.65 vol) at ambient temperature to form a solution.
Separately, a solution of 1M lithium aluminum hydride in diethyl
ether solution (1.0 eq) and diethyl ether (2.48 vol) was prepared
and added at .ltoreq.23.degree. C. over 60 minutes, with subsequent
reflux at 34-35.degree. C. for 17 hours 40 minutes. Hydroquinone
(0.023 eq) was then charged and the reaction slowly quenched via
the drop-wise addition of purified water at .ltoreq.25.degree. C. A
solution of potassium sodium tartrate tetrahydrate (0.95 eq) in
purified water (3.31 vol) was prepared and charged to the
suspension at ambient temperature, with subsequent agitation for 1
hour at 23.degree. C. A grey bi-phasic "sludge" was formed with
large clumps of by-products present. TLC analysis indicated the
reaction was complete (90:10 cyclohexane:ethyl acetate eluent).
Diethyl ether extractions of the aqueous sludge were problematic,
with poor phase separation and blockages of the outlet valve during
discharge from the vessel. After drying over magnesium sulphate,
washing and concentration, 17.4 g (90% yield) of crude
di-n-butyltin dihydride was obtained. This was purified via high
vacuum distillation. Di-n-butyltin dihydride was collected at 5-12
mbar between .about.56-74.degree. C. as colorless oil in .about.65%
yield. It was found that this reaction was not robust, and would be
challenging to scale-up, mainly due to the difficult work-up.
##STR00027##
Example 1b
Synthesis of Di-n-Butyltin Dihydride 1-2, Via NaBH.sub.4
[0151] The following reduction with NaBH.sub.4 was adapted from
methods described by A. G. Hernan et al., Journal of Organometallic
Chemistry, 691, (2006), pp 1466-1475.
[0152] Small-Scale:
[0153] Sodium borohydride (5.33 eq) was dissolved in purified water
(11.3 vol) at 0.degree. C. and deoxygenated by bubbling nitrogen
for 30 minutes. A solution of di-n-butyltin dichloride (9.0 g, 1.0
eq) was prepared in 11.3 vol of diethyl ether and added slowly over
a period of 45 minutes, with the solution then stirred for a
further 15 minutes once addition was complete. The product
containing organic layer was the separated, washed with purified
water (2.times.2.78 vol), dried over magnesium sulphate, filtered
and concentrated under vacuum to give di-n-butyltin dihydride as a
colorless oil (6 g, 85% yield). .sup.1H NMR confirmed the
di-n-butyltin dihydride was formed. To ensure high purity
di-n-butyltin dihydride was produced, distillative purification was
added.
[0154] Large Scale:
[0155] The sodium borohydride-based reduction was successfully
scaled to 90 g. The reduction was again complete by TLC after 20
minutes and work-up proceeded to give 67.6 g (97% yield) of crude
di-n-butyltin dihydride. This underwent distillative purification
from a 1.0 L RBF with Vigreux column. No foaming was observed and
53.5 g (77% yield) of dihydride was collected as a clear colorless
liquid between 5-6 mbar at 56.degree. C. .sup.1H and .sup.13C NMR
confirmed di-n-butyltin dihydride had been collected. GC analysis
indicated a purity of >99% area. Although the lower aqueous
phase during the washing step was still a suspension it was much
less problematic to separate from the upper product containing
diethyl ether phase, relative to the corresponding reaction with
LiAlH.sub.4. This reduction via NaBH.sub.4 was quicker, more robust
and higher yielding than the corresponding reaction with
LiAlH.sub.4.
##STR00028##
Example 2
Synthesis of
1-(3-Bromobenzyl)-2,2,5,5-tetramethyl-1,2,5-azadisololidine,
1-8
[0156] Free-Basing:
[0157] 3-Bromobenzylamine hydrochloride (1.0 eq) was dissolved in
purified water (15.8 vol) at ambient temperature. Separately sodium
hydroxide (1.05 eq) was dissolved in purified water (0.83 vol) and
added to the above solution at ambient temperature and agitated for
30 minutes. The freebase was extracted using 3.times.5.0 vol
dichloromethane washes, which were dried over magnesium sulphate
prior to filtration to remove the drying agent and subsequent
rotary concentration to dryness at 35 to 40.degree. C.
3-Bromobenzyl amine freebase was obtained as a yellow/orange oil in
.about.100% yield.
[0158] Reaction:
[0159] 3-Bromobenzylamine (48.7 g, 1.0 eq) was dissolved in
dichloromethane (7.4 vol) and triethylamine (2.75 eq) to form a
solution, which was cooled under nitrogen to 0-5.degree. C.
Separately a solution of 1,2-bis(chlorodimethylsilyl)ethane (1.0
eq) in dichloromethane (5.13 vol) was prepared and added drop-wise
over .about.30 min at 0-5.degree. C. The resultant suspension was
allowed to warm to ambient and stir for a minimum of 14 hours after
which the reaction was filtered to remove by-products, the wet-cake
washed with dichloromethane (2.times.1.54 vol) and concentrated to
a crude oil at 35-40.degree. C. in vacuo. The crude product was
triturated with hexane (6.2 vol) to further precipitate
by-products, filtered and the wet-cake washed with hexane
(2.times.1.54 vol). The filtrate was again concentrated to a crude
oil at 40-45.degree. C. in vacuo. Distillation purification was
used to isolate
1-(3-bromobenzyl)-2,2,5,5-tetramethyl-1,2,5-azadisololidine which
was collected between 150-160.degree. C. between 5-10 mbar as a
colorless oil in .about.62% yield.
##STR00029##
Example 3
Synthesis of Polymer Comprising Monomer I-7
[0160] 3,4-Divinylbenzene was purified using a silica gel column to
remove radical scavengers prior to usage in this process.
Di-n-butyltin dichloride (0.97 eq) was dissolved in filtered
divinylbenzene (1.23 eq) at ambient temperature then cooled to
<10.degree. C. Di-n-butyltin dihydride (1.0 eq) was then charged
to the reaction mixture followed by filtered divinylbenzene (1.18
eq) and AIBN (0.040 eq). Cooling was removed and the solution
agitated at <30.degree. C. for 14 to 18 hours to form the
monomer I-4.
[0161] To this was then charged a solution of methylcellulose (15
cPs, 0.023 w/w) in purified water (8.94 vol) at ambient temperature
followed by filtered divinylbenzene (0.55 eq), 1-octanol (3.7 vol)
and AIBN (0.065 eq). The resultant suspension was heated to reflux
at (.about.98-102.degree. C.) at .about.500 rpm and agitated for
7-9 hours to form polymer comprising monomer I-7. Heating was
removed and the mixture agitated for at least 14 hours prior to the
addition of purified water (9.6 vol).
[0162] Polymer comprising monomer I-7 was collected by filtration
and re-slurried a further five times with purified water (each 9.6
vol) with isolation by filtration. This was followed by the
following re-slurries, each of which is isolated by centrifugation:
Acetone (5.times.7.7 vol); Methanol (2.times.7.7 vol); Toluene
(3.times.7.7 vol); and THF (2.times.7.7 vol).
[0163] Polymer comprising monomer I-7 was then dried in vacuo to
constant weight (<1% loss on drying over 1 hour minimum) at
ambient temperature. Yield 56%.
##STR00030##
Example 4
Synthesis of Polymer Comprising Monomer I-10
[0164] 1-(3-Bromobenzyl)2,2,5,5-tetramethyl-1,2,5-azadisilolidine
(1.06 eq.) was charged to a flask followed by tetrahydrofuran (8.75
vol.) and the solution cooled to <-65.degree. C. 2.5M n-butyl
lithium in hexane (1.06 eq.) was added over 30 minutes. Polymer
comprising monomer I-7 was added in a single dry portion after
which the reaction mixture is stirred at <-65.degree. C. for 7-9
hours then allowed to warm to room temperature for 1-2 hours.
Methanol was added followed by 1M HCl (aq.) to adjust the pH to
4-5. The polymer comprising monomer I-10 was then collected by
centrifugation. The liquid was decanted and polymer comprising
monomer I-10 washed sequentially with methanol (4.times.6.25 vol.),
methanol/water (1:1) (2.times.6.25 vol.), methanol (4.times.6.25
vol.) and then dried in a vacuum oven giving polymer comprising
monomer I-10 in a yield of 82%.
##STR00031##
Example 5
Guanidinylation of Polymer Comprising Monomer I-10 to Form Polymer
Comprising Monomer (Ia) HCl
[0165] Toluene (8.6 vol.) was charged to a flask and heated to
54-56.degree. C. Polymer comprising monomer I-10 (1.0 eq.) was
added, followed by cyanamide (9.13 eq.) and triethylamine (0.018
eq.). The reaction mixture was stirred at 54-56.degree. C. for
24-26 hours then cooled to ambient temperature. Polymer comprising
monomer (Ib) was isolated by centrifugation and washed sequentially
with acetonitrile (4.times.4.7 vol), methanol (4.times.4.7 vol.)
and acetonitrile (2.times.4.7 vol.). The isolated polymer was dried
in a vacuum oven at ambient temperature.
[0166] Applicants identified cyanamide coupling reaction time (24
to 26 hours) and temperature (54-56.degree. C.) as critical
parameters for controlling impurity formation, particularly mIBBG.
A 10 g trial of this reaction was performed to monitor impurity
formation between .about.20 to 48 hours during cyanamide coupling
at 54 to 56.degree. C. At each time point analyzed, .about.2.5 ml
of the suspension was removed, filtered and washed with 5.times.5
mL of methanol prior to vacuum drying at ambient temperature.
[0167] The results of these experiments showed a gradual decrease
in mIBA starting material from 0.35% at 19.5 hours to 0.09% after
48 hours. The mIBBG impurity gradually increased to 1.02%, but only
after 48 hrs. Within a 15 to 30, 18 to 28, or more particularly
24-26 hour reaction time window, the reaction appears to give a
good balance between low residual mIBA, whilst not elevating mIBBG
formation.
[0168] The above-described impurity time point formation
experiments suggest that the process, in some embodiments, should
be operated within the supplied process parameters of e.g.,
50-60.degree. C. for 15 to 30 hours, 52-58.degree. C. for 20 to 28
hours, or, more particularly, 54-56.degree. C. for 24 to 26
hours.
##STR00032##
Example 6
Counter Ion Exchange of Polymer Comprising Monomer (Ia) HCl to Form
and Purify Polymer Comprising Monomer (Ib) HOAc
[0169] Step 1:
[0170] Counter ion exchange of polymer comprising monomer (Ia)
hydrochloride salt was achieved by slurrying in 1M sodium acetate
in 70% aqueous ethanol, followed by and centrifugation (9.times.4.3
vol.).
[0171] Step 2:
[0172] The resulting polymer comprising monomer (Ib) HOAc salt was
purified by washing with 95% aqueous ethanol (8.times.4.3 vol.)
then isolated by filtration under nitrogen using an appropriate
clean, dry Buchner flask and funnel. Polymer comprising monomer
(Ib) (84%. yield) was dried in a vacuum oven at ambient
temperature.
[0173] Step 3:
[0174] Vacuum was stopped and the Buchner funnel containing polymer
comprising monomer (Ib) was charged with absolute ethanol
(4.times.4.30 vol) under nitrogen gas. The absolute ethanol washes,
under nitrogen, were found to further purify polymer comprising
monomer (Ib) and remove traces of water from the wet-cake.
Example 7
Analytical Methods for Determination of Leachable Tin Levels by
ICP-MS
[0175] Concentrations of leachable tin in polymer comprising
monomer (Ib) were determined according to the general analytical
methods outlined in the Tables below.
TABLE-US-00002 TABLE 1 Instruments, Equipment, Materials and
Reagents Description Instruments ICP-MS Agilent 7900 Balance
Minimum 5 place balance Pestle and Mortar Flask Shaker Stuart
Scientific Equipment Plasticware Various sizes of volumetric flasks
and measuring cylinders Plastic 50 ml, 15 ml, and 10 ml tubes of
centrifuge suitable grade with tubes volume markings Auto pipettes
Varying capacity from 50 .mu.l to 5000 .mu.l Plastic 500 ml
volumetric pipettes Syringes 10 ml Syringe filters PTFE Acrodisc
0.2 .mu.m Materials Indium (In) Standard Tin (Sn) Standard Cerium
(Ce) Standard Cobalt (Co) Standard Yttrium (Y) Standard Tuning
solution Reagents Water UHQ Grade Ethanol Absolute
NitricAcid(67-70%) ICP-MS grade Hydrochloric Acid 20% ICP-MS
Grade
TABLE-US-00003 TABLE 2 Preparation of Reagents Reagent Description
Storage Expiry Diluent A 5% Ethanol Ambient 1 25 ml Absolute
Ethanol diluted to month 500 ml in volumetric flask Diluent B 2%
Nitric Acid Ambient 1 29.4 mL Concentrated Nitric acid month made
up to 1 L in a volumetric flask
TABLE-US-00004 TABLE 3 Internal Standard Preparation Make to Volume
With Solution Replicates Add (mL) Diluent Storage Expiry 2 ppm In 1
5.0 ml of 10 ppm 25 ml B Ambient 10 Internal In Internal days
standard standard 2 ppm Sn 1 1.0 ml of 100 ppm 50 B Ambient 10
Standard Sn Standard days 2 ppm Sn 1 1.0 ml of 100 ppm 50 B Ambient
10 Check Sn Standard days Standard
TABLE-US-00005 TABLE 4 Working Standard Preparation Make to With
Solution Add volume (ml) Diluent Storage Expiry Calibration 1 ml
concentrated nitric acid + 50 ml in UHQ ambient 10 Blank 2.5 ml
ethanol and 0.5 ml plastic water days internal standard centrifuge
tube. 50 ppb 2.5 ml of 2 ppm Sn Standard + 100 ml UHQ Ambient 10
working 5.0 ml Ethanol + 1.0 ml of water days standard Internal
Standard + 2.0 ml conc. Nitric acic 150 ppb 7.5 ml of 2 ppm Tin
Standard + 100 ml UHQ Ambient 10 working 5.0 ml Ethanol + 1 ml of
water days standard Internal Standard + 2.0 ml conc. Nitric acid 50
ppb check 2.5 ml of 2 ppm Sn check 100 ml UHQ Ambient 10 standard
Standard + 5.0 ml Ethanol + water Days 2.0 ml conc. Nitric acid
Sample Preparation Steps:
[0176] 1. Using a pestle and mortar, grind enough drug to weigh the
below to a fine powder. [0177] 2. In a clean Teflon 50 ml
centrifuge tube, accurately weigh approximately 40 mg of drug
material. [0178] 3. Add 10.0 ml of 5% ethanol. [0179] 4. Shake on
low for 1 hour. [0180] 5. Filter through 0.45 .mu.m PTFE filters
into a HDPE bottle. Add 1 drop of 2% nitric acid to the sample.
[0181] 6. Prepare a Method blank with the samples by proceeding
through the above steps using UHQ water in place of the sample.
Prepare the method blank and the samples in singular. Store at
ambient with an expiry date of 6 days.
TABLE-US-00006 [0181] TABLE 5 Instrument Parameters: The ICP-MS
instrument is to be set up with the following parameters as an
example: Parameter Setting Forward Power (7500c) 1500, (7500a) 1300
Acquire Integration Time 0.10 sec Sn and 0.05 sec In per point
Integration Mode Auto Replicates 3 Points per peak 3 Validated
masses .sup.118Sn, .sup.120Sn Preferred Mass .sup.118Sn Internal
Standard Mass .sup.115In Rinse Time 100 sec(may be increased if
needed) Rinse rate 0.5rps Rinse Solution 1% HNO.sub.3 and HCl
Uptake time 40 sec (may be increased if needed) Uptake rate 0.5 rps
Stabilization Time 20 sec Analysis Pump Rate 0.1 rps Spray Chamber
Quartz Double Pass Nebulizer Concentric Nebulizer Flow rate 0.95 to
1.16 L/min All other settings Determined by Tune
TABLE-US-00007 TABLE 6 Tuning Requirements Parameter Setting Tuning
Masses .sup.59Co, .sup.89Y, .sup.140Ce Resolution @ .sup.59Co,
.sup.89Y, .sup.140Ce .+-.0.10 AMU, W-10% 0.65 to 0.80 Minimum CPS
.sup.89Y, .sup.140Ce 200,000 (20,000 Counts/0.1 sec) .sup.89Y,
.sup.140Ce % RSD .ltoreq.10% Oxide 156/140 AMU .ltoreq.2% Double
Charged 70/140 AMU .ltoreq.5%
TABLE-US-00008 TABLE 7 Interference Equations Affected Isotope
Correction .sup.120Sn 120 * 1-125 * 0.01344726 .sup.115In 115 *
1-118 * 0.01403799
TABLE-US-00009 TABLE 8 Isotope LOQ's Isotope LOQ (.mu.g/L)
.sup.118Sn 0.3 .sup.120Sn 0.3
Method Procedure
[0182] 1. Set up the ICP-MS according to the parameters listed in
(Tables 5-7) and Instrument SOP. [0183] 2. Perform a tune using the
tuning solution. Tune the ICP-MS to obtain the desired resolution,
sensitivity, oxide ratio and doubly charged ratios as specified in
Table 6. Perform a P/A factor using the 150 ppm Tin Standard.
[0184] 3. Prepare the standards and sample solutions as per above
sections and the Sample Preparation Steps. [0185] 4. Add 75 .mu.L
if Indium internal standard to 7.5 ml of filtered sample and mix.
Load the samples and standards in the auto-sampler. [0186] 5.
Calibrate the instrument with the calibration blank and the 50 ppm
standard. [0187] 6. Run the blank as a sample after the calibration
is complete. The blank must read less than the LOQ (Table 8). If
the blank is out of specification, investigate the cause and
correct the problem before continuing with the analysis. [0188] 7.
Run the calibration check standard as a sample after the blank is
run. The check standard must read 50 ppm.+-.5 ppm, and the RSD
between the 3 replicate instrument readings must be less than 4%.
If the check standard is out of specification, investigate the
cause and correct the problem before continuing with the analysis.
[0189] 8. Analyze the method blank. It is best if the method blank
reads less than the LOQ (Table 8). If the method blank is above
these values, but the element concentration in the sample is
greater than 10 times the method blank level or less than the LOQ,
the samples can be run as prepared. If the element concentration in
the samples is less than 10 times the method blank level, but above
the LOQ, re-prepare both the blank and the samples. Take any
necessary steps to achieve a clean blank. [0190] 9. Analyze the
samples. Samples may be diluted further as needed to bring within
the linear range. The upper limit of the linear range verified
during validation is 5000 .mu.g/L. Maintain acid strength on all
dilutions and total internal standard concentration of 20 .mu.g/L
indium in all dilutions. [0191] 10. Analyze the 50 ppm calibration
standard and the blank after every 10 samples, or at the end of the
samples, whichever comes first. Do not run more than 10 samples
before running the 50 ppm standard and a blank. The 50 ppm standard
must read 50 ppm.+-.5 ppm, the RSD between the 3 replicates
instrument readings must be <4% and the blank must read less
than the LOQ. If the 50 ppm standard or the blank is out of
specification, the instrument must be recalibrated and all samples
analyzed from the time of the last acceptable standard and the
blank must be rerun. [0192] 11. Analyze the 50 ppm standard and the
blank at the end of the analysis. The 50 ppm standard must read 50
ppm.+-.5 ppm, the RSD between the 3 replicate instrument readings
must be <4%, and the blank must read less than the LOQ. If the
50 ppm standard or the blank is out of specification, the
instrument must be recalibrated and all samples analyzed from the
time of the last acceptable standard and blank must be rerun.
[0193] 12. Place the instrument in standby mode according to
SOP.
TABLE-US-00010 [0193] TABLE 9 Analysis - Perform the Following
Typical Injection Sequence ICP-MS Wash X Cal Blank X Calibration
Standards X Wash X IQC standard X Wash X Samples (including
duplicates) X Spiked sample(s) X Wash X Check standard after 10
sample and end of X sequence Wash X
TABLE-US-00011 TABLE10 Calculations .mu.g _ sample g = ( C .times.
D .times. V ) ( W ) ##EQU00001## C Concentration of element read
from the instrument in .mu.g/L V Volume of sample preparation, in
mL W Weight of sample used, in mg D Dilution factor (A dilution of
1 mL to 50 mL final volume would yield a D of 50)
[0194] Conversions for the mass and volume units are incorporated
into the above equation. Report data as .mu.g/g of tin in the
sample. Concentration can be read from the calibration curve
directly. If the sample requires dilution to have an element
concentration within the calibration range, the dilution factor
must be taken into account when determining the final concentration
in the sample.
Example 8
Comparative Analysis of Leachable Tin Level in Samples of Polymer
Comprising Monomer (Ib) Compositions Prepared According to Methods
Disclosed in U.S. Pat. No. 7,658,910
TABLE-US-00012 [0195] TABLE 11 Leachable Tin by ICP-MS Conditions
Result (Sn) Range at time = 0 155-318 ppm Mean (n = 9) = 198.3 +/-
SD 84.5 ppm Range after three 576-660 ppm years at -20.degree. C.
Range after three 818-928 ppm years at 25.degree. C., 60% relative
humidity Range after three 847-1207 ppm years at 40.degree. C., 75%
relative humidity
The above analyses shows that leachable tin was present at high
levels (e.g., 155-318 ppm) in Polymer (Ib) prepared according to
methods disclosed in U.S. Pat. No. 7,658,910. The analysis further
shows that levels of leachable tin increased over time due to
exposure to moisture, O.sub.2 and/or ambient and elevated
temperature.
Example 9
Analysis of Leachable Tin Levels from Samples of Polymer Comprising
Monomer (Ib) Compositions Prepared According to Methods of Examples
1-6
TABLE-US-00013 [0196] TABLE 12 Leachable Tin by ICP-MS Storage
Conditions and Result (Sn) GMP lots, unless stated otherwise
Duration 25.degree. C. 60% 40.degree. C. 75% (in months)
-20.degree. C. Relative Humidity Relative Humidity 0 18-19 ppm 19
ppm 19 ppm (GMP lot) 7.9 ppm (non-GMP lot) Mean (n = 2) = 13 ppm 1
20 ppm 243 ppm 582 ppm 3 14 ppm 304 ppm 636 ppm 6 15 ppm 327 ppm
447 ppm 9 12 ppm 476 ppm GMP = Good manufacturing practices
The above analyses shows that leachable tin was present at reduced
levels (e.g., 7.9-19 ppm), for extensive durations, in Polymer (Ib)
prepared according to the present methods of examples 1-6.
Example 10
Analytical Method for Determination of Moisture Content by Oven
Coulometric Karl Fischer Titration
TABLE-US-00014 [0197] TABLE 13 Instruments, Equipment, Materials
and Reagents Description Instruments KF Coulometer With oven
sampler Balance Minimum 5 place Equipment Generating Cell without
diaphragm, Mettler electrode Dried overnight at 75.degree. C. prior
to use Vials, seals & cap Desiccator Silica Gel Reagents
Anolyte Karl Fischer Reagent AG-oven (Sigma Aldrich Catalogue No.
34739 or equivalent) Gas Type Nitrogen, flow set to 150-200
mL/min
TABLE-US-00015 TABLE 14 Instrument Parameters Parameter Value
Sample Parameters Type Mass Minimum (g) 0.135 Maximum (g) 0.165
Entry Before Speed (%) 40 Mix time (s) 300 Set Temperature
160.degree. C. Control Parameters Current (.mu.A) 2.0 End point
(mV) 100 Gen.speed Normal Termination Parameters Max. time (s) 1200
Drift stop Rel. Drift (.mu.g/min) 15 Blank (.mu.g) Auto Drift
Request Calculation 1 R1 = X [%] * f1 F1 = 1.000 Unit % Decimal
Places 2 Statistics Yes Max. srel (%) 0.000 Calculation 2 R2 = X
[mg] * f2 F2 = 1.000 Unit mg Decimal Places 3 Statistics Yes Max.
srel (%) 0.000 Standby Yes Report Output Print. + Comp. Type
GLP
TABLE-US-00016 TABLE 15 Test Vials - Prepare the test vials as
described in the table below. Close immediately with a seal and
cap. Solution Replicates Add Storage Expiry Drift Vial 1 Aluminum
insert Ambient Use immediately Blank Vial 1 N/A Ambient Use
immediately Sample 2 150 mg (.+-.10%) Ambient Use immediately Vial
sample
TABLE-US-00017 TABLE 16 Analysis - Perform the following analysis
sequence: Water Determination Blank X Sample 1 replicate 1 X Sample
1 replicate 2 X Sample 2 replicate 1 X Sample 2 replicate 2 X . . .
up to a maximum of 13 analyses . . .
TABLE-US-00018 TABLE 17 Calculations Water Water content is
calculated by the instrument according to the Content following
equation: Water Content ( % w / w ) = { Water - [ B + ( D .times. T
) ] } 1000 .times. 100 W sample .times. 1000 ##EQU00002## Where
Water = Water content (.mu.g) B = Blank (.mu.g) D = Drift
(.mu.g/min) T = Titration Time (minutes) W.sub.sample = Weight of
sample (g) Ensure that replicate results agree within: If water
content <0.1% no limit 0.1%-1.0% agree within 0.2% absolute
>1.0% agree within 0.5% absolute
TABLE-US-00019 TABLE 18 Reporting Water Content Report the mean of
two replicates. Report results <0.3% w/w as <0.3% w/w. Record
the data on an analytical worksheet/workbook. Compare the results
obtained against the relevant specification limit. If the results
obtained are in compliance with the specification limit report the
results on the RFA form. If the results fail to meet the
specification, initiate an OOS investigation.
Example 11
Moisture Content Analysis for Compositions of Polymer Comprising
Monomer (Ib) Prepared According to Methods of Examples 1-6
TABLE-US-00020 [0198] TABLE 19a Moisture content Test Specification
Result Residual Moisture (Water .ltoreq.1.5% 0.92% (GMP) Content by
Karl Fischer) at 1.0% (non-GMP) time = 0
TABLE-US-00021 TABLE 19b Moisture content over various durations
Storage conditions and Results (Residual Moisture i.e.; Water
Content by Karl Fischer) GMP lots, unless stated otherwise Duration
25.degree. C. 60% 40.degree. C. 75% (in months) -20.degree. C.
Relative Humidity Relative Humidity 0 0.92% (GMP) 0.92% 0.92% 1.0%
(non- GMP) 1 0.99% 0.86% 1.1% 3 0.60% 1.6% 0.78% 6 0.80% 0.71%
0.89% 9 0.67% 0.89%
Example 12
Analytical Method for the Determination of Residual Solvents in
Composition of Polymer Comprising Monomer (Ib), Using GC Headspace
Analysis
TABLE-US-00022 [0199] TABLE 20a Instruments, Equipment, Materials
and Reagents (Alternative A) Description Instruments GC Gas
chromatograph with FID and Headspace Sampler Balance Minimum 5
place balance Equipment Column RES-SOLV 30 m .times. 0.53 mm 1.00
.mu.m Liner 4 mm ID open tube liner (Agilent Septa 210-3003) High
temperature - Bleed/Temp optimized (Agilent 5183- 4757 or
equivalent) Glassware Grade A Headspace vials 20 mL Materials
ARS5483 Isopropyl acetate ARS5496 Tetrahydrofuran Reagents DMSO
Analytical Grade
TABLE-US-00023 TABLE 20b Instruments, Equipment, Materials and
Reagents (Alternative B) Description Instruments GC Gas
chromatograph with FID and Headspace Sampler Balance Minimum 5
place balance Equipment Column ZB-624, 60 m .times. 0.53 mm, 3.00
.mu.m Liner 2 mm ID open tube liner (Agilent5181-88-18) Septa High
temperature - Bleed/Temp optimized (Agilent 5183-4757 or
equivalent) Glassware Grade A Headspace vials 20 mL Materials ARS
5443 Diethylether ARS5916 Dichloromethane ARS5815 Triethylamine
ARS5413 Hexane ARS5467 Acetone ARS5414 Methanol ARS5402 Toluene ARS
5814 Tetrahydrofuran ARS5424 Acetonitrile ARS5465 Ethanol ARS5828
1-Octanol Reagents Analytical Grade N,N- dimethylacetamide
(DMA)
TABLE-US-00024 TABLE 21 Preparation of reagents Reagent Description
Storage Expiry Blank & DMSO (or N,N-dimethylacetamide Ambient 1
month Standard/ (DMA)) Use single bottle for Sample entire analysis
Diluent
TABLE-US-00025 TABLE 22a Instrument Parameters (Alternative A)
Value GC Oven Parameters Initial temperature 40.degree. C. Initial
time 1.70 minutes Total run time 15.37 minutes Rate Final Final
hold (.degree. C./min) Temperature (.degree. C.) time (min)
Temperature ramp 6.00 90.0 0 30.00 250.0 0 Inlet Parameters Mode
Split Initial Temperature 220.degree. C. Split ratio 7:1 Gas Type
Helium Column Parameters Column RES-SOLV, 30 m .times. 0.53 mm, 1.0
.mu.m Mode Constant Flow Initial flow 4.9 Values Detector
Parameters Temperature 260.degree. C. Hydrogen flow 45 mL/minute
Air flow 450 mL/minute Mode Constant makeup flow Make up flow
(Nitrogen) 10 mL/minute Headspace Parameters Oven Temperature
130.degree. C. Loop Temperature 140.degree. C. Transfer Line
Temperature 150.degree. C. GC Cycle 25 minutes Vial Equilibration
Time 15 minutes Vial Pressurisation Time 0.2 minute Loop Fill Time
0.15 minute Loop Equilibration Time 0.05 minute Injection Time 1
minute Agitation High
TABLE-US-00026 TABLE 22b Instrument Parameters (Alternative B)
Value GC Oven Parameters Initial temperature 45.degree. C. Initial
time 3.0 minutes Total run time 26.0 minutes Rate Final Final hold
(.degree. C./min) Temperature (.degree. C.) time (min) Temperature
ramp 10.00 255.0 2.0 Inlet Parameters Mode Split Initial
Temperature 220.degree. C. Split ratio 7:1 Gas Type Helium Column
Parameters Column ZB-624, 60 m .times. 0.53 mm, 3.0 .mu.m Mode
Constant Flow Initial flow 4.0 mL/min Values Detector Parameters
Temperature 300.degree. C. Hydrogen flow 45 mL/minute Air flow 450
mL/minute Mode Constant makeup flow Make up flow (Nitrogen) 10
mL/minute Headspace Parameters Oven Temperature 130.degree. C. Loop
Temperature 140.degree. C. Transfer Line Temperature 155.degree. C.
GC Cycle 32 minutes Vial Equilibration Time 15 minutes Vial
Pressurisation Time 0.2 minute Loop Fill Time 0.2 minute Loop
Equilibration Time 0.2 minute Injection Time 1 minute Agitation
High
TABLE-US-00027 TABLE 23 Test Solutions - Prepare test solutions as
described in the table below. Transfer 5 mL of test solutions to
individual 20 mL GC headspace vials, preparing one vial for each
injection required. Prepare sample solutions directly into GC
headspace vials. Make to Volume Test with diluent Material
Replicates Add (mL) Storage Expiry Stock 1 ~50 mL diluent 100
Ambient 24-40 Standard 1 1000 mg ARS5483 hours Stock 1 ~50 mL
diluent 100 Ambient 24-40 Standard 2 360 mg of ARS5496 hours
Working 1 10.0 mL of Stock Standard 1 100 Ambient 24-40 Standard
and 1.0 mL Stock Standard 2 hours Samples 2 250 mg (.+-.10 mg) 5 -
Alternative A Ambient 24-40 Alternative A 2 - Alternative B hours
100 mg (.+-.10 mg) Alternative B
TABLE-US-00028 TABLE 24 Analysis - A typical run sequence is shown
below. Sequence Number of Injections Blank 1 Standard 1 Standard 1
Working Standard 1-6 Blank 1 Sample 1 replicate 1 1 Sample 1
replicate 2 1 Blank 1 Sample 2 replicate 1 1 Sample 2 replicate 2 1
. . . up to a maximum of 7 injections between bracketing standards
. . . Standard 1
TABLE-US-00029 TABLE 25a Data Processing (Alternative A)
Integration Integrate each named solvent peak in the standard and
if present in the test solutions. Residual Solvent Typical
Retention Time (minutes) Typical retention Tetrahydrofuran 3.4
times Isopropyl acetate 4.0 Ensure the following System Suitability
Criteria are met: Parameter Injections Acceptance criteria System
Suitability Retention Time First 3 RSD .ltoreq.2% Criteria
Standards for each solvent Response First 3 RSD .ltoreq.15%
Standards for each solvent Retention Time All standards RSD
.ltoreq.2% for each solvent Response All standards RSD .ltoreq.15%
for each solvent Retention Time All samples Within .+-.0.5 minutes
of mean Std retention time
TABLE-US-00030 TABLE 25b Data Processing (Alternative B)
Integration Integrate each named solvent peak in the standard and
if present in the test solutions. Residual Solvent Typical
Retention Time (minutes) Typical retention Diethyl ether 6.3 times
Dichloromethane 7.4 Triethylamine 10.3 Hexane 8.1 Acetone 6.7
Methanol 5.1 Toluene 12.6 Tetrahydrofuran 9.5 Acetonitrile 7.2
Ethanol 6.1 1-Octanol 18.5 Ensure the following System Suitability
Criteria are met: Parameter Injections Acceptance criteria System
Suitability Retention Time First 6 RSD .ltoreq.2% Criteria
Standards for each solvent Response First 6 RSD .ltoreq.15%
Standards for each solvent Retention Time All standards RSD
.ltoreq.2% for each solvent Response All standards RSD .ltoreq.15%
for each solvent Retention Time All samples Within .+-.0.5 minutes
of mean Std retention time
TABLE-US-00031 TABLE 26 Calculations Residual Solvent Calculate the
concentrations of Tetrahydrofuran and Isopropylacetate using
Content the following equation: Residual Solvent Content ( ppm ) =
R Sample .times. W standard .times. DF sample .times. 1000000 R
standard .times. W sample .times. DF standard ##EQU00003## Where:
R.sub.sample = Response for solvent in sample R.sub.standard = Mean
response for all standard injections W = Weight of sample or
standard (mg) DF = Dilution factor of sample or standard Ensure the
replicate results agree within 100 ppm absolute for results <500
ppm and within .+-.25% for results .gtoreq.500 ppm. Reporting Limit
(LOQ) Reporting Limit ( ppm ) = W standard .times. DF sample
.times. 1000000 .times. 10 W sample .times. DF standard .times. N
##EQU00004## Where: W.sub.sample = Nominal sample weight (mg)
W.sub.standard = Weight of solvent in standard (mg) N = Signal to
noise ratio of solvent in first standard DF = Dilution factor of
sample or standard
TABLE-US-00032 TABLE 27 Reporting Residual Solvent Report the
amount of each residual solvent present Content at .gtoreq. the
reporting limit (LOQ), to the nearest integer. Report all solvents
not present or present at less than the reporting limit as
`<LOQ`.
Example 13
Analysis of Residual Solvents in Composition of Polymer Comprising
Monomer (Ib), Prepared According to Methods of Examples 1-6, as
Determined by GC Headspace Analysis
TABLE-US-00033 [0200] TABLE 28 Residual Solvents Results Results
non- Results non- Residual Solvents Specification GMP GMP lot A GMP
lot B by GC (ppm) lot (ppm) (ppm) (ppm) Diethyl ether .ltoreq.5000
<1 7 <1 Dichloromethane .ltoreq.600 <11 ND <11
Triethylamine Report result <2 ND <2 Hexane .ltoreq.290 <1
ND <1 Acetone .ltoreq.5000 21 21 <3 Methanol .ltoreq.3000 47
58 <5 Toluene .ltoreq.890 <3 ND <3 Tetrahydrofuran
.ltoreq.720 <2 ND <2 Acetonitrile .ltoreq.410 <5 56 <5
Ethanol .ltoreq.5000 479 4530 156 1-Octanol Report result <101
ND <101 ND = not detected
Non-GMP lot A, having 4530 ppm ethanol, was subjected to re-drying
under vacuum under a stream of nitrogen, and converted to non-GMP
lot B, having 156 ppm ethanol.
Example 14
HPLC Analytical Method for the Determination of Purity, Impurities
and Leachable Degradation Products from Polymer Comprising Monomer
(Ib)
TABLE-US-00034 [0201] TABLE 29 Instruments, Equipment, Materials
and Reagents Instruments HPLC Reversed Phase HPLC system with UV
detection Equipment Column Waters XBridge C18, 100 .times. 4.6 mm,
3.5.mu.rm Materials m-lodobenzylguanidine (mlBG) m-lodobenzylamine
hydrochloride (mIBA) m-lodobenzylbiguanidine (mIBBG)
Benzylguanidine (BG) m-hydroxybenzylguanidine (mHBG)
TABLE-US-00035 TABLE 30 Preparation of Reagents Reagent Description
Storage Expiry Mobile 0.1% TFA/2.0% ACN in water Ambient 7 days
Phase A (Typically add 1 mL TFA and 20 mL acetonitrile to 500 mL of
water in a volumetric flask and dilute to 1000 mL with water)
Mobile 0.1% TFA in Acetonitrile Ambient 1 month Phase B (Typically
add 1 mL TFA to 500 mL acetonitrile in a volumetric flask and
dilute to 1000 mL with acetonitrile) Buffer C Phosphate Buffer, pH
7.4 2-8.degree. C. 7 days (Typically dissolve 0.13 g (.+-.2%)
NaH.sub.2PO.sub.4 and 0.54 g (.+-.0.011 g) Na.sub.2HPO.sub.4 in 490
mL water, adjust pH to 7.4 if necessary with 1M NaOH or phosphoric
acid and dilute to 500 mL with water) Diluent D 1.0 mg/mL Sodium
Thiosulphate in phosphate buffer 2-8.degree. C. 7 days (Typically
dissolve 100 mg (.+-.10 mg) sodium thiosulphate in Buffer C and
dilute to 100 mL with Buffer C) Diluent E UHQ water Ambient 7 days
Solution F Oxidant solution Ambient Prepare Mix 1.34 mL 30%
Hydrogen peroxide and 0.2 mL acetic fresh on acid in a 5 mL
volumetric flask. each day Dilute to volume with UHQ water. of use
Solution G 0.02M sodium sulphate/0.1M sodium Hydroxide in water
Weigh 56.8 mg (.+-.2.84 mg) into a 20 mL volumetric flask and
dilute to volume with 0.1M sodium hydroxide. Solution H Sodium
Iodide Stock Solution Weigh 400 mg (.+-.40 mg) into a 20 mL
volumetric flask and dilute to volume with Solution G.
TABLE-US-00036 TABLE 31 Instrument Parameters Parameter Value
Sample Temperature Ambient Column Temperature +.degree. C.
(.+-.2.degree. C.) Flow Rate 2.0 L/minute Time (minutes) % A % B
Gradient 0 100 0 1 100 0 12 74 26 13 50 50 15 50 50 16 100 0 20 100
0 Total Run Time 20 minutes Wavelength 210 nm Injection Volume 20
.mu.L and 100 .mu.L (refer to injection sequence) Needle Wash 90/10
v/v Water/Acetonitrile
TABLE-US-00037 TABLE 32 Standard Dilutions Make to Volume volume
With Test Solution Stock Solution (mL) (mL) Diluent Storage Expiry
System Primary Stock 0.2 10 D Ambient 24 hours Suitability
solutions (200 .mu.L) Stock Solution of each System System 1.0 10 D
Ambient 4 days Suitability Suitability Solution 2% Stock Solution
Sensitivity System 0.15 1 D Ambient 24 hours solution 0.3%
Suitability Solution 2%
TABLE-US-00038 TABLE 33 Purity, Impurities and Leachables Sample
Solutions - Note: Impurities are determined by iodinating the
3-benzyl guanidine supported on the resin and determining the
purity and impurities of the mlBG product. Prepare the sample
solutions as described in the table below. Solution Replicates
Preparation Storage Expiry Purity & Impurities 3 As detailed
Ambient 75 hours Sample below Purity & Impurities 2 Ambient 75
hours Matrix Blank Leachables Sample 2 Ambient 49 hours Leachables
Blank 1 Ambient 49 hours Purity and impurities Sample and Matrix
Blank Preparation procedure Weigh 80 mg (.+-.8.0 mg) sample into a
20 mL volumetric flask. For blank matrix preparation, omit sample.
Add in the following order: 1) 0.5 mL ethanol, swirl and stand for
5 minutes minimum to wet. 2) 2.0 mL water (Diluent E). 3) 1.0 mL
solution H. 4) 0.5 mL Solution F. Vortex the mixture for 5 seconds.
Mix reaction mixture on a flask shaker at 500 for 60 minutes.
Dilute to volume with UHQ water (Diluent E), Transfer the mixture
to a centrifuge tube and centrifuge for 15 minutes at 4000 rpm.
Dilute 4.0 mL supernatant liquid of blank and one of the samples
only to 25 mL with Diluent D. Analyze the prepared sample according
to Sample Concentration Check sequence. Calculate volume of stock
sample required for each of two remaining samples to obtain a mIBG
concentration of 100 .mu.g/mL .+-. 20%. Prepare the blank and the
other two samples by diluting calculated volume of supernatant
liquid to 25 mL with Diluent D. Analyze the prepared samples
according to Purity, Impurities and Leachables sequence. Leachables
Sample and Blank Preparation procedure Weigh 20 mg (.+-.2.0 mg)
sample into a COC vial. For blank preparation, omit Add 7.5 mL
water (Diluent E). Mix for 5 seconds. Incubate the vials at room
temperature at 20-28.degree. C. for 60 .+-. 10 min. Filter the
samples and blank through a 0.2 .mu.m PTFE syringe filter. Analyze
samples without any further dilution.
TABLE-US-00039 TABLE 34 Data Processing Typical retention time of
Typical retention mlBG: -10.3 minutes time Peak RT (min) RRT mHBG
3.85 0.38 BG 5.85 0.57 mIBA 8.16 0.79 mIBBG 9.54 0.93
Example 15
Determination of Purity, Impurities and Leachable Degradation
Products in Compositions of Polymer Comprising Monomer (Ib),
Prepared According to the Methods of Examples 1-6
TABLE-US-00040 [0202] TABLE 35a Purity, Impurities and Leachable
Degradation Products in Polymer (Ib) at time = 0 months Results
non- Test Specification Results GMP lot GMP lot Purity by HPLC:
.gtoreq.98% MIBG (iobenguane) MIBG 99.2% MIBG 99.1% reaction with
iodine .ltoreq.1.0% MIBA MIBA 0.27% MIBA 0.39% .ltoreq.1.0% MIBBG
MIBBG MIBBG Report unknown impurities <0.15% <0.16%
.gtoreq.0.3% area Unknown Unknown impurities: impurities: 0.26%
Area 0.34% Area Leachable TOC in .ltoreq.1% <0.01% 0.24% water
HPLC assay of Benzylguanidine .ltoreq.0.1% Benzylguanidine:
Benzylguanidine: leachable degradation (.ltoreq.0.04 .mu.g/mL) Not
Detected <0.01% products Meta-hydroxy- Meta-hydroxy-
Meta-hydroxy- benzylguanidine .ltoreq.0.1% benzylguanidine:
benzylguanidine: (.ltoreq.0.04 .mu.g/mL) Not Detected <0.01%
Total unknown impurities Total unknown Total unknown .ltoreq.0.5%
(.ltoreq.0.2 .mu.g/mL) impurities: impurities: 0.01% ND ND = not
detected
TABLE-US-00041 TABLE 35b Purity and Impurities in Polymer (Ib) over
time Storage Conditions and Results (GMP lot, purity over time at
various conditions) 25.degree. C. 60% 40.degree. C. 75% Duration
Relative Relative (in months) & -20.degree. C. Humidity
Humidity 0 MIBG % 99.2 99.2 99.2 MIBA % 0.27 0.27 0.27 MIBBG %
<0.15 <0.15 <0.15 Unknown impurities: 0.26 0.26 0.26 %
Area 1 MIBG % 99.2 99.5 99.4 MIBA % <0.3 <0.3 <0.3 MIBBG %
<0.3 <0.3 <0.15 Unknown impurities: 0.27 <0.3 <0.28
% Area 3 MIBG % 99.2 99.3 99.1 MIBA % <0.3 0.25 <0.3 MIBBG %
<0.3 <0.3 <0.3 Unknown impurities: <0.3; <0.3
<0.3; <0.3 0.32; <0.3; <0.3 % Area (two runs) (two
runs) (three runs) 6 MIBG % 99.3 99.3 98.8 MIBA % <0.3 <0.3
<0.3 MIBBG % <0.3 <0.3 <0.3 Unknown impurities:
<0.3; <0.3 <0.3; 0.26 0.59; <0.3; <0.3 % Area (two
runs) (two runs) (three runs) 9 MIBG % 99.0 98.8 MIBA % 0.3 0.3
MIBBG % <0.3 <0.3 Unknown impurities: <0.3; 0.3; <0.3
five runs, % Area (three runs) all <0.3
Example 16
Iobenguane Formulation
[0203] Iobenguane was prepared from (Ultratrace.RTM.) polymer
comprising monomer (Ib), where the polymer was prepared according
to the methods of Examples 1-6. Iobenguane was formulated and
sealed in vials as described below in Table 36.
TABLE-US-00042 TABLE 36 Iobenguane Formulation Total Fill Volume
1.5-2.5 mL/vial Total Fill 20-25 mL/vial (Dosimetry) Volume
(Therapeutic) Active [I-131]-MIBG Storage .ltoreq.-70.degree. C.
Pharmaceutical Condition Ingredient: Container 30 mL sterile, empty
evacuated vial (Hollister Stier P/N 7521ZA) Closure 20 mm Lyo
NovaPure Stopper (West/19700311) 20 mm Aluminum seal
(Wheaton/224178-01) Standard Test Method Specification Acceptance
Criteria Method Type DESCRIPTION Appearance Clear solution, free of
visible QC-STM-0034 Visual particles Inspection IDENTIFICATION
TESTS Radiochemical [I-131]-MIBG retention time is 90-110%
QC-STM-0026 HPLC-UV- Identification of reference standard
Radiometric Detection Radionuclidic Gamma Photon Emission at 364
.+-. USP <821> Gamma Identity 10 keV spectroscopy ASSAY @ TOC
MIBG 0.001-0.010 mg/mL QC-STM-0026 HPLC-UV concentration Ascorbate
48-64 mg/mL QC-STM-0016 HPLC-UV Gentisate 20-25 mg/mL QC-STM-0016
HPLC-UV Radioactive 13.5-16.5 mCi/mL @ TOC QC-STM-0026 Dose
Concentration Calibrator Total 20-42 mCi/vial @ TOC USP <821>
Dose Radioactivity Calibrator (Dosimetry) Total 270-413 mCi/vial @
TOC USP <821> Dose Radioactivity Calibrator (Therapeutic)
PHYSICAL TESTS pH 4.5-5.5 QC-STM-0021 pH meter RADIOCHEMICAL PURITY
TESTS Radiochemical .gtoreq.96% QC-STM-0026 HPLC- Purity
Radiornetric Detection Total .ltoreq.4 QC-STM-0026 HPLC-
radiochemical Radiornetric impurities (free I- Detection 131 and
other impurities) MICROBIOLOGICAL TESTS Bacterial .ltoreq.2 EU/mL
STM-MIC- USP <85> by Endotoxins GEN-10- gel-clot 0001 method
Sterility No growth MIC-STM-0005 USP <71> by Membrane
Filtration Filter Integrity .gtoreq.47 psi PRD-STM- Bubble Test
0001 Point
Example 17
Phase II Study Evaluating the Efficacy and Safety of
Ultratrace.RTM. Iobenguane I-131 in Patients with Malignant
Relapsed or Refractory Pheochromocytoma/Paraganglioma
Objectives--Primary Objective:
[0204] To determine the proportion of study subjects with a
reduction (including discontinuation) of all antihypertensive
medication by at least 50% for at least six months or two cycles,
from two Therapeutic Doses each at 500 mCi (or 8 mCi/kg, for
subjects weighing 62.5 kg or less) of Ultratrace iobenguane I 131
administered approximately three months apart.
Objectives--Secondary Objectives:
[0205] To evaluate the safety of Ultratrace iobenguane I 131 in
subjects with malignant pheochromocytoma/paraganglioma, including
human radiation absorbed dose-estimates to normal organs.
[0206] To assess the proportion of subject with overall tumor
response of complete response (CR) or partial response (PR) per
RECIST criteria
[0207] To assess the proportion of subjects with overall tumor
response of CR, PR or MR, (moderate response, i.e., decrease in the
sum of the longest diameters of the target lesions of 15-30%, with
no evidence of progressive disease [PD] in non-target per RECIST
criteria
[0208] To assess bone lesion status on the Soloway Scale
[0209] To assess tumor marker response in 24 br urine and other
serum/plasma tumor markers associated with
pheochromocytoma/paraganglioma.
[0210] To describe changes from baseline in the overall quality of
life through the EORTC QLQ-C30 questionnaire post-treatment
[0211] To describe changes from baseline in symptoms using the
National Institute of Health (NIH) Quality of Life and Symptoms
Questionnaire of Pheochromocytoma and Paraganglioma post
treatment
[0212] To assess change in use of analgesics and pain
medications
[0213] To describe Karnofsky Performance Status post-treatment
[0214] To assess overall survival, up to 5 years post-treatment
Study Design
[0215] This is a multi-center, open-label, single arm study. It is
anticipated that approximately 75 subjects will be enrolled to
ensure fifty-eight subjects given two Therapeutic Doses each at 500
mCi (or 8 mCi/kg for subjects weighing 62.5 kg or less) of
Ultratrace iobenguane I 131 will be evaluable for efficacy and
safety. Prior to administration of the first Therapeutic Dose,
subjects will be given an Imaging Dose (3 mCi-6 mCi) of: Ultratrace
iobenguane I 131 and will undergo iobenguane I 131 scintigraphic
scans to evaluate tumor avidity as wells to measure normal organ
distribution and allow for the calculation of radiation dosimetry
to normal organs. Both Therapeutic Doses for a subject will be
appropriately decreased by the same amount if results of the
dosimetry study indicate an adjustment is warranted.
[0216] Tumors will be measured by computed tomography (CT) or
magnetic resonance (MR) at baseline and at 3, 6, 9 and 12 months
after the first Therapeutic Dose. A bone scan will be performed at
Screening/baseline, and if probable metastatic disease. is observed
additional bone scans will be performed at Months 3, 6, 9, and 12.
Overall tumor response at 3, 6, 9 and 12 months per RECIST criteria
will be assessed centrally by independent, blinded readers. If the
study site has the capability to perform flurodeoxyglucose (FDG)
scans, they may be performed to assess viable tumor tissue at
baseline and 3, 6, 9, and 12 months. Tumor markers [serum
chromogranin A, plasma free metanephrines and normetanephrines, 24
hour urinary vanillylmandelic acid (VMA), plasma catecholamines
(dopamine, epinephrine and norepinephrine), 24 hour urinary
catecholamines (dopamine, epinephrine and norepinephrine) and
urinary metanephrines and normetanephrines will be evaluated by a
central laboratory at intervals described in the protocol. Renal
function will be assessed through either creatinine clearance or
Glomerular Filtration Rate (GFR) at baseline and at the Months 6
and 12 Effficacy Visits. Evaluation of thyroid function (T3 T4 and
TSH) and clinical evaluation of possible dry mouth will be
performed at the 12 month Efficacy Visit. Use and dose of
antihypertensive, pain and other medication required for tumor
associated signs and symptoms will be recorded on an on-going
basis, including on an outpatient basis. Subject-reported Quality
of Life measurements will be obtained through the EORTC QLQ-C30 v3
and the NIH Quality of Life and Symptoms Questionnaire for
Pheochromocytoma and Paraganglioma. The frequency of the procedures
is summarized in the Schedule of Procedures.
[0217] Safety will be assessed through analyses of treatment
emergent adverse events (AEs), as well as baseline and pre- and
post-infusion ECGs, physical examinations, vital signs
measurements, laboratory measurements (including clinical
chemistry, hematology and urinalysis), and human radiation absorbed
dose estimates to target lesions and normal organs.
Study Duration
[0218] Subjects will attend study visits from the time of signed
informed consent through 12 months after the first Therapeutic Dose
of Ultratrace iobenguane I 131. They will then enter long-term
follow-up, and remain in follow-up for 5 years after the first
therapeutic dose.
Inclusion Criteria
[0219] All subjects must: 1. Provide written informed consent (and
assent for subjects less than 18 years of age) and be willing to
comply with protocol requirements 2. Be at least 12 years of age 3.
Have a documented (medical record) diagnosis of either
pheochromocytoma or paraganglioma that was confirmed by histology
or a physician using other supportive data (e.g., abnormal
metaiodobenzyl guanidine (MIBG) diagnostic study, or elevated tumor
markers). 4. Be ineligible for curative surgery for
pheochromocytoma 5. Have failed a prior therapy for
pheochromocytoma/paraganglioma or are not candidates for
chemotherapy or other curative therapies 6. Be on stable
antihypertensive medication regimen for tumor-related hypertension
for at least 30 days prior to the first therapeutic dose. A stable
antihypertensive medication regimen is defined as no addition or
deletion of antihypertensive medication and no change in total
daily dose or route of administration for currently used
antihypertensive medication(s) in the 30 days prior to first
therapeutic dose. 7. Have at least one tumor site by CT or MR or
iobenguane I 131 scan 8. Have definitive MIBG tumor avidity 9. Have
an expected survival period of at least 6 months as prognosticated
by physician
Exclusion Criteria
[0220] Subjects will be excluded if any of the following conditions
are observed: 1. <50% of FDG (if data are available) positive
lesions are MIBG avid. 2. Pregnant or nursing females 3. Active
central nervous system (CNS) lesions by CT or MR scanning within 3
months of study entry 4. New York Heart Association class IV heart
failure, symptomatic congestive heart failure [New York Heart
Association class IV with another medical disorder], unstable
angina pectoris, cardiac arrhythmia 5. Received any previous
systemic radiotherapy resulting in marrow toxicity within 3 months
of study-entry or have active malignancy (other than
pheochromocytoma/paraganglioma) requiring additional treatment
during the active phase or follow up period of the Ultratrace
iobenguane I 131 trial. (Prior iobenguane I 131 therapy is allowed
if not within 3 months prior to the first therapeutic dose). 6.
Administered prior whole-body radiation therapy 7. Received
external beam radiotherapy to >25% of bone marrow 8.
Administered prior chemotherapy within 30 days of study entry or
have active malignancy (other than pheochromocytoma/paraganglioma)
requiring additional treatment.
9. Karnofsky Performance Status is <60
10. Platelets <80,000/.mu.L
[0221] 11. Absolute neutrophil count (ANC)<1,200/.mu.L 12. Total
bilirubin >1.5 times the upper limit of normal 13. AST/SGOT or
ALT/SGPT>2.5 times the upper limit of normal 14. Diagnosed with
AIDS or HIV-positive per patient medical history 15. Active chronic
alcohol abuse, chronic liver disease (excluding liver metastases),
or hepatitis (A, B or C, detected by positive testing for HbsAg and
anti-HCV as stated in patient medical history) 16. Renal
dysfunction/impairment (defined as creatinine clearance of <30
mL/min or Glomerular Filtration Rate (GFR) of <30 mL/min)
because of the possibility of delayed Ultratrace iobenguane I 131
excretion and increased whole body dose 17. Known allergy to
iobenguane that has required medical intervention 18. Received a
therapeutic investigational compound and/or medical device within
30 days before admission into this study 19. Receiving a medication
which inhibits tumor uptake of iobenguane I 131 20. Any medical
condition or other circumstances (i.e., uncontrolled current
illness including but not limited to, ongoing or active infection
or psychiatric illness/social situations that would limit
compliance with the study requirements). 21. Any other condition,
that in the opinion of the investigator, may compromise the safety
or compliance of the subject or would preclude the subject from
successful completion of the study
Study Drug
[0222] Each subject will be administered 3 mCi to 6 mCi Ultratrace
iobenguane I 131, referred to as the Imaging Dose, to confirm that
subject meets radiological entry criteria and to establish
dosimtetry. All subjects meeting entry criteria will then receive
the investigational product referred to as the Therapeutic Dose
(500 mCi or 8 mCi/kg if the subject weighs 62.5 kg or less) of
Ultratrace iobenguane I 131, followed by imaging within 7 days post
infusion. The Therapeutic Doses will be adjusted equally if
warranted by results of the dosimetry evaluation. At least 3 months
later, subjects will receive the second Therapeutic Dose.
Imaging Parameters
[0223] During the baseline period, CT or MR scans of the chest,
abdomen and pelvis with IV contrast (unless medical condition or
allergy prevents its use) and a bone scan will be acquired to
determine extent of disease. Obtaining renal volume for each kidney
is required. Anatomical volumes may be measured for other organs
and tissues to further evaluate absorbed dose.
[0224] After the Imaging Dose (3 mCi to 6 mCi) of Ultratrace
iobenguane I 131, subjects will have an Ultratrace iobenguane I 131
anterior and posterior planar whole body scan at 1 hour, 1-2 days
and 2-5 days following the dose to evaluate biodistribution and
(for the first dose) to confirm uptake in at least one known tumor
that meets RECIST criteria. At least 18 hours separation between
each of the image acquisitions is required. The tumor to background
ratio should be >2, and may be best visualized beginning at the
24 hour image to allow background clearance. For example, a liver
lesion should be 2X background normal liver while soft tissue
lesions would use background in surrounding soft tissue.
[0225] Subjects will have an Ultratrace iobenguane I 131 whole body
scan within 7 days following each Therapeutic Dose to further
assess biodistribution.
[0226] Subjects will have follow-up CT or MR scans at 3, 6, 9 and
12 months after the first Therapeutic Dose of Ultratrace iobenguane
I 131 to assess tumor response. Subjects may also have optional
follow up FDG scans at 3, 6, 9 and 12 months after the first
Therapeutic Dose of Ultratrace iobenguane I 131. Bone scans will be
performed at Month 3, 6, 9, 12, if probable metastatic disease is
observed on the Screening bone scan. Subjects may undergo
additional scars at unscheduled visits for confirmation of
response.
[0227] All images will be sent to the central imaging core lab for
evaluation after anonymization. Off-site. CT or MR assessment will
be conducted by independent, CT and MR-experienced readers in
accordance with the charter issued by the imaging core laboratory.
These readers will be blinded to clinical subject information as
described in the Imaging Charter. The readers will determine
objective tumor response according to RECIST criteria. On-site
interpretation of CT or MR images may also be performed, but only
the results of the blinded read will be used for the objective
tumor response evaluations.
[0228] As part of long-term follow-up, a subject may receive
additional scans to monitor disease status per institutional
standard of care; these images will not be evaluated by a central
laboratory.
Endpoints--Primary Endpoint:
[0229] The primary endpoint for this trial is the proportion of
study subjects with a reduction (including discontinuation) of all
antihypertensive medication by at least 50% for at least six months
or two cycles Ultratrace iobenguane I 131. The primary endpoint
will be assessed at the time of study completion or
discontinuation, whichever occurs first.
Endpoints--Secondary Endpoints:
[0230] Proportion of subjects with overall tumor response of CR or
PR per RECIST criteria,
[0231] Proportion of subjects with overall tumor response of CR, PR
or MR (moderate response) per RECIST criteria
[0232] Bone lesion response per the Soloway Scale
[0233] Tumor marker response in 24 hr urine and other serum/plasma
tumor markers associated with pheochromocytoma/paraganglioma
[0234] Status of hypertension and changes in blood pressure
[0235] Quality of-Life per the recommended guidelines from the
EORTC QLQ-C30 manual
[0236] Symptoms as evaluated through the NIH Quality of Life and
Symptoms Questionnaire for Pheochromocytoma and Paraganglioma.
[0237] Change in use of analgesics and pain medications
[0238] Overall survival (OS), defined as the time from the date of
enrollment to the date of death from any cause. OS time will be
censored at the last date the subject is known to be alive when the
confirmation is absent or unknown.
[0239] Safety assessed by changes in lab values, physical exams or
vital signs, and the occurrence of treatment emergent adverse
events
[0240] Human radiation absorbed dose estimates to normal organs
Sample Size
[0241] It is anticipated that approximately 75 subjects will be
enrolled to ensure that 58 subjects receive two doses and are
evaluable for safety and efficacy. The one-sided alternative
hypothesis of the study is that the proportion of subjects
experiencing a reduction (including discontinuation) of all
antihypertensive medication by at least 50% for at least six months
or two cycles is 0.25, against the null hypothesis that the
proportion is 0.10. Sample size of 58 subjects in the Per Protocol
Set was based on a one-sided significance level of .alpha.=0.025
and power of 0.90 (90%).
Example 18
Comparison of Leachable Tin Levels in Compositions Comprising
MIBG
[0242] Provided are exemplary methods to compare leachable tin
levels in compositions comprising MIBG prepared from polymer
comprising a monomer of formula (I). Such polymers may be prepared,
for example, according to (a) methods described in U.S. Pat. No.
7,658,910, (to yield relatively high levels of leachable tin) or
(b) methods of Examples 1-6 (to yield relatively low levels of
leachable tin).
[0243] Low levels of leachable tin are desirable in the cleaved
MIBG product formed by iodination of a relatively tin-free
dialkylstannane-functionalized polymeric drug substance precursor
(DSP), prepared according to methods of Examples 1-6. Low levels of
leachable tin in the DSP are expected to afford an iodinated drug
substance likewise containing low levels of tin. Tin is a Class 3
impurity according to U.S. and other regulatory authorities.
[0244] By contrast, relatively high levels of leachable tin in the
polymer methods prepared according to methods described in U.S.
Pat. No. 7,658,910 may carry through to the MIBG drug substance
after its cleavage from the resin by iodination. Tin levels in MIBG
may be investigated in order to provide quantitative data on the
extent to which high and low levels of leachable tin content in the
polymer precursor affect the leachable tin levels in the MIBG drug
substance.
[0245] Without being bound by theory, leachable tin levels in
polymer comprising a monomer of formula (I) generally derive from
solvolysis of the organostannane linkage between the arylguanidine
moiety and the poly(divinylbenzene) resin. This solvolysis reaction
can be mediated by residual solvents, e.g., ethanol and water, both
of which may be used, in some embodiments, in the final washing
sequence prior to vacuum drying. A comparison of washing and drying
steps are provided in Table 1 below for methods described in U.S.
Pat. No. 7,658,910 relative to those in Examples 1-6.
TABLE-US-00043 Washing Drying Methods described 95:5 EtOH:H.sub.2O
Vacuum desiccator at ambient in U.S. Pat. No. (10 washes by Buchner
temperature, to constant weight 7,658,910 filtration) Methods of
95:5 EtOH:H.sub.2O 3 Stage Drying sequence in Vacuum Examples 1-6
(8 washes by centrifugation) Oven EtOH (anhydrous) 1) Ambient
temperature with N.sub.2 (6 washes by Buchner flow, no vacuum, 1-2
hours filtration) 2) Ambient temperature with N.sub.2 flow, full
vacuum, .gtoreq.14 hours 3) 30 .+-. 3.degree. C. with N.sub.2 flow,
full vacuum, .gtoreq.14 hours to constant weight
[0246] A single batch of polymer comprising a monomer of formula
(I) can be manufactured through an ion exchange step whereby
polymer-supported benzylguanidinium chloride is exchanged to the
acetate salt form. Prior to the final washing and drying sequence,
the resin can be split into two sub-lots and the final washing and
drying sequence performed separately on each sub-lot according to
(a) methods described in U.S. Pat. No. 7,658,910 or (b) methods of
Examples 1-6. Both sub-lots can be analyzed by full release
testing. In this manner, batches of resin can be manufactured
according to (a) methods described in U.S. Pat. No. 7,658,910
(yielding relatively high levels of residual tin) or (b) methods of
Examples 1-6 (yielding relatively low levels of residual tin).
[0247] Both of sub-lots (a) and (b) can then be subjected to
iodination using the method of Example 14 above; the respective
MIBG solutions thus formed can then each be tested by ICP-MS for
tin content using methods, such as that of Example 19 below. As
leachable tin has been observed by Applicants to increase
substantially during storage when the resin is packaged after the
washing and drying procedures in U.S. Pat. No. 7,658,910, a further
aspect of this experiment would be to perform a stability study,
whereby respective resins are stored for 1, 3, and 6 months at
reduced temperatures (e.g., -20.degree. C.). At each timepoint the
analyses can be performed, including (1) analyses of each resin for
leachable tin content, and following iodination of each polymer,
(2) tin content testing on each of the cleaved MIBG drug substances
or pharmaceutical compositions comprising the same.
Example 19
Representative ICP-MS Protocols
1. Scope
[0248] This procedure is suitable for the determination of elements
detectable by ICP-MS in matrices that yield relatively clear
aqueous solutions by dissolution, acid digestion and microwave
digestion. The method also covers matrices that yield clear
solutions in organic solvents with low carbon content such as
Methanol, Ethanol and DMSO.
[0249] ICP-MS can be used to conduct analyses for, but is not
limited to, the following elements Al, Au, As, B, Ba, Be, Bi, Ca,
Cd, Ce, Co, Cr, Cs, Cu, Er, Eu, Fe, Ga, Gd, Hg, Ho, Hf, In, Ir, K,
La, Li, Lu, Mg, Mn, Mo, Na, Nd, Ni, Os, P, Pb, Pd, Pr, Pt, Re, Rb,
Rh, Ru, Sb, Se, Sm, Sn, Sr, Ta, Te, Th, TL, Tm, U, V, W, Zn and
Zr.
[0250] The range of this technique is generally effective for, but
not limited to, a concentration of analyte between 0.1 mg/kg-1000
mg/kg in sample.
[0251] The analyst should be aware that certain element
combinations may result in poor solubility after digestion e.g.
silver and chloride, barium and sulphur. However, 10% HCl will keep
up to 10 .mu.g/mL Ag in aqueous solution due to complexation (Ag+
in solution as the Ag(Cl).sup.X-(X-1)).
[0252] Elements not suited to this method include: Silicon, which
can precipitate in acid solutions, and Titanium (if from TiO.sub.2)
which has poor solubility.
[0253] Not all organic materials can be digested using microwave
techniques. For aqueous solutions, the following are special cases
and may need to be prepared separately: Osmium: Nitric acid should
not be used. Use Hydrochloric acid instead. Silver: dilute
Hydrochloric acid should be avoided. Tin: solution should be
prepared in 10-20% Hydrochloric Acid.
2. Instruments, Equipment, Materials and Reagents
TABLE-US-00044 [0254] Description Instruments ICP-MS Agilent 7900
Balance Minimum 5 place balance Microwave Mars 5 Equipment Plastic
ware Various sizes of volumetric flasks and measuring cylinders
Plastic Centrifuge 50 mL, 15 mL and 10 mL Tubes tubes of suitable
grade with volume markings Auto Pipettes Varying capacity from 50
.mu.L to 10000 .mu.L Materials 10 ppm, 1000 ppm or 10000 ppm stock
standards (single or multi-element solutions). Other stocks can be
used if CoA is provided. Reagents Water UHQ Nitric Acid 67-70%
ICP-MS Grade Hydrochloric Acid 35% ICP-MS Grade Hydrogen Peroxide
30% ICP-MS Grade Other ICP grade reagents can be used if
required.
3. Instrument Setup for Organic (e.g. Methanol, Ethanol and DMSO or
their Mixtures with Aqueous Acidic Solutions)
[0255] Change torch to 1.5 mm ID, remove ISTD tubing, put the
needle into a 1 ppb Agilent tune solution (aqueous), turn on the
plasma and do only Torch Axis Setting of the start-up. Switch off
the plasma and wait for standby. Change the plasma mode in the
hardware window to organic solvent and switch off SC cooling (for
DMSO only).
[0256] Load and Adjust Suitable Organic Solvent Template
[0257] Prepare 1 ppb tune solution by diluting with the organic
matrix (DMSO, Ethanol or other solvents). Add 1% HNO.sub.3 to the
organic tune solution for better stability. Go to Tune, run Auto
Tune then save the template as a batch with suitable name. Edit
sample list and add to the queue. Note: [0258] It is recommended to
add 1-5% acid to all organic samples and standards for better
stability [0259] Waste tubing should be organic for DMSO. [0260]
Sample tubing should be Tygon MH3 (Glass Expansion) or equivalent.
[0261] Ni cones can be used for Ethanol and DMSO. However, Pt cones
are better and they should be used for solvents with higher carbon
content.
4. Preparation of Reagents
TABLE-US-00045 [0262] Reagent Description Storage Expiry Diluent A
Water (or organic if instrument is Ambient 7 days set up for
organics)
[0263] The diluent for samples and calibration standards/internal
standards/QCs should be matched if possible.
5. Standards Preparation
[0264] 5.1 General Consideration
[0265] Analysts should be careful when using mixed element
standards that the final matrix is suitable for all the elements in
that standard regardless of whether they are needed in the analysis
e.g. silver will precipitate from dilute hydrochloric acid
solutions.
[0266] Standard solutions should be matrix matched as closely as
possible to the samples with respect to nitric and hydrochloric
acid concentration (or organic content in case organic solvents are
used)
[0267] As a minimum, the following calibration solutions are
required: [0268] Calibration blank [0269] Two calibration standards
[0270] Independent check standard as per above sections [0271]
Reporting/specification limit standard as per above sections. This
standard may be used as one of the calibration standards (can be
skipped if the limit is too high to be included in the
analysis).
[0272] All standard solutions require the addition of one or more
internal standards. Alternatively, online internal standard
addition can be used.
[0273] Typically standards prepared at 1.0 ppb and 10 ppb provide
an acceptable range. If only trace levels are expected, the 10 ppb
standard may be replaced with a 0.1 ppb standard. If higher levels
are expected, the 1 ppb may be replaced with a 100 ppb standard.
These concentrations are only meant as a guide. Alternative
concentrations may be prepared if more applicable to the range and
reporting requirement of the customer.
[0274] To reduce the risk of contamination, calibration solutions
are made up in capped 50 mL plastic centrifuge tubes. The tubes
have calibrated volumetric markings and must be used for dilution
of solutions that do not contain internal standard or where
internal standard is introduced online. The volume scale on
uncalibrated tubes may be used for the final dilution as accurate
dilution to the final volume is not necessary where internal
standard is added.
[0275] Acid concentrations should not exceed 10% v/v for ICP-MS
analysis while implementing nickel cones.
[0276] All standard preparations must be clearly documented in the
analyst's raw data. Standards at higher concentrations may be
prepared where results are over range, but linearity must be
demonstrated. This can be achieved by adding the additional
standard solutions to the analytical run. If the response is within
10% of expected, linearity is confirmed.
[0277] 5.2 Preparation of Internal Standard
[0278] The following may be used as a dilution scheme for preparing
internal standards; however alternative schemes that do not
compromise on accuracy are also acceptable:
[0279] Prepare the internal standard and standard solutions as
described in the table below. These internal standard solutions
provide a range of masses suitable for routine use, however,
alternative elements may be used if deemed more appropriate.
TABLE-US-00046 Make to Volume With Solution Replicate Add (mL)
Diluent Storage Expiry 1000 ppb 1 5 mL of 10 ppm 50 A Ambient 7
days Mixed stock (Scandium, Internal yttrium, indium, Standard
terbium and bismuth standards) + 1 mL of nitric acid 200 ppb 1 1 mL
of 10 ppm 50 A Ambient 7 days Mixed stock (Scandium, Internal
yttrium, indium, Standard for terbium and Online bismuth standards)
+ Addition 1 mL of nitric acid
[0280] 5.3 Calibration Standards--Preparation
[0281] The following may be used as a dilution scheme for preparing
calibration standards; however alternative schemes that do not
compromise on accuracy are also acceptable: Prepare the stock
standard solution (secondary mix standard) as described in the
table below.
TABLE-US-00047 Make to Volume With Solution Replicates Add (mL)
Diluent Storage Expiry 1000 ppb 1 0.5 mL 10 ppm Hg + 50 A Ambient 7
days Secondary 5 mL of stock metal Mixed standard (10 ppm) Standard
as required + (100 ppb Hg) 1 mL of nitric acid
[0282] Calibration Blank
[0283] Add acid to deionised water in a 50 mL centrifuge tube to
match the concentration in the final sample preparations. Add 0.5
mL of the mixed internal standard solution and dilute to volume
with water
[0284] 1 ppb Mixed Working Standard (0.1 ppb Hg)
[0285] Add 0.05 mL of the secondary mixed standard to a 50 mL
plastic centrifuge tube. Add acid as for the calibration blank and
0.5 mL of the mixed internal standard solution. Dilute to
volume.
[0286] 10 ppb Mixed Working Standard (1 ppb Hg)
[0287] Add 0.50 mL of the secondary mixed standard to a 50 mL
plastic centrifuge tube. Add acid as for calibration blank and 0.5
mL of the mixed internal standard solution. Dilute to volume.
[0288] 100 ppb Mixed Working Standard (10 ppb Hg)
[0289] Add 5.00 mL of the secondary mixed standard to a 50 mL
plastic centrifuge tube. Add acid as for calibration blank and 0.5
mL of the mixed internal standard solution. Dilute to volume.
[0290] Expiry
[0291] The calibration standards should be prepared fresh for each
analysis and not stored for longer than 24 hours. Note: it is
advised that Mercury calibrations do not exceed 1 Oppb due to its
longer washout times in the instrument. Calibration solutions
containing mercury will require a matrix containing 1% hydrochloric
acid.
6. Quality Control Preparation
[0292] An independent QC (IQC) standard should be prepared from an
alternate stock source and analysed after the calibration. Results
for IQC standards must be within 85-115% of the expected
(certified) value.
[0293] One sample must be analysed in duplicate for every batch or
part of a batch of 10 provided sufficient material is available.
Typically the difference between two results should be within 10%
of the mean, but this will not always be achievable (when measuring
near the instrument quantitation limit, for example).
TABLE-US-00048 Number of Samples Number of Duplicates 1-10 1 11-20
2 21-30 3 31-40 4
[0294] If matrix effects are anticipated, a sample should be spiked
with each element to be determined before digestion or dissolution
(if appropriate). Spike recovery must be within 85-115% of target
for quantitative analysis. The spike concentration should be
appropriate to the requirement of the test. For limit tests a spike
at the specification limit would be appropriate. Spike recoveries
provide information regarding collective effect of matrix
interferences and analytical procedures recoveries, and should be
performed at least once for each matrix type in the batch if matrix
effects are anticipated. Recoveries are normally calculated as a
percentage of spike added, against spike detected after subtraction
of the contribution from the sample. However where the contribution
from the sample exceeds the spike amount added, the recovery may be
expressed as a percentage of the total element detected against the
total element expected. When spiking at the specification for limit
tests, lower recoveries may be accepted provided that the
concentration of the element in the test solution is less than half
the concentration in the spike solution.
[0295] If a clear solution cannot be obtained, a sample should be
spiked with each element to be determined before preparation.
Centrifuging slightly turbid solutions are acceptable and data will
be verified from the performance of the spike recovery which must
be within 85-115% of target.
[0296] Internal standard is required for all analysis and is added
at a suitable concentration. Recovery of the internal standard must
be in the range 70%-130%. Alternatively, online internal standard
addition can be used and MassHunter will monitor internal standard
variation between run. This should be in the range 70%-130%.
[0297] A calibration standard should be prepared at the required
reporting/specification limit (if applicable). The calculated
concentration must be within 80-120%. (can be skipped if the limit
is too high to be included in the analysis)
7. Sample Preparation and Handling
[0298] If complete dissolution is achieved using diluted acid (e.g.
10% HNO3). Digestion is not required.
[0299] Acid digestion using concentrated acid can be an alternative
if dissolution is not achievable using diluted acid.
[0300] Microwave digestion is to be used if acid digestion does not
give clear solution. Refer to A01-189 for microwave digestion.
Check that the material is suitable for digestion.
[0301] Organic solvents are an alternative option instead of
digestion where suitable.
[0302] Ensure the sample is homogenous. Lumpy samples should be
crushed and blended with a plastic spatula prior to sampling.
[0303] The EasyPrep should be acid cleaned prior to use. A cleaning
run using the digestion acid mix to be used for samples should be
performed. Note: acids used for cleaning should not be the high
purity grades used for sample analysis. Analar grades or equivalent
are considered suitable for this purpose.
[0304] When performing trace analysis, the maximum sample weight
that can be digested is approximately 0.5 g. Typically, this will
be digested in 10 mL of acid.
[0305] Prepare a spike and duplicate preparation using the same
size aliquot where possible as required by the QC requirements. The
spike is prepared by adding a suitable aliquot of the secondary
mixed standard prior to the addition of digestion. It is
recommended that the quantity of spike added matches the
specification limit for the sample, or a quantity equivalent to the
amount expected in the sample.
[0306] If a reduced volume of acid is used, purified water must be
added to make the total volume of liquid 10 mL.
[0307] Digest the samples in accordance with microwave digestion
AOI-189 at 210.degree. C.
[0308] When digestion is complete, the sample is transferred to a
50 mL plastic centrifuge tube. If mercury is to be determined,
hydrochloric acid should be added so that the preparation has a
nominal concentration of 10% hydrochloric acid. For example, if 10
mL nitric acid has been used in digestion, then 5 mL of
hydrochloric acid should be added at this stage. Where reverse
aquaregia has been used, an additional 2 mL of nitric acid and 3 mL
of hydrochloric should be added. The solution is diluted to 50 mL
with water. Samples requiring tin or silver will require a further
5 mL of hydrochloric acid to be added before making up to volume to
give a 20% hydrochloric acid solution.
[0309] Further dilute the preparation so that the acid
concentration does not exceed 10% v/v. In general, 1.0 mL of the
digest stock and 0.10 mL of the mixed internal standard solution is
diluted to 10 mL with water. Alternate dilution ratio may require
adjustment to the acid volume added. See sections above. In general
working solutions should contain 2% nitric acid and 1% hydrochloric
acid (if mercury is required).
[0310] All solutions prepared for MS analysis must be clear without
any precipitate. The presence of insoluble material in the digested
sample may mean that the preparation method is unsuitable for
analysis or incomplete. Further digestion after adding 2 mL
hydrogen peroxide may be tried.
[0311] If a clear solution cannot be obtained, centrifuging
slightly turbid solutions are acceptable (see sections above). Data
will be verified from the performance of the spike recovery.
General Notes:
[0312] The sample preparation technique detailed above is intended
as a generic outline; any combination of acids may be employed if
it is known to be beneficial and provides a clear aqueous solution
after digestion. [0313] For most applications nitric acid alone is
suitable, but nitric and hydrochloric acids (8:2 known as reverse
aquaregia) are used for palladium, silver, tin, gold and platinum.
Alternative acids can be used if solubility is satisfactory. [0314]
For materials that are difficult to digest (e.g. plastics), the
addition of 1 mL of hydrogen peroxide to the nitric acid may also
be used. [0315] Solutions for mercury require a final matrix
containing 1% hydrochloric acid to ensure stability and good
washout times in the instrument. [0316] The total inorganic solids
must not exceed 0.3% in the final test solution for ICP-MS
analysis. [0317] Digested sample solutions should not be considered
stable for more than 1 week and dilutions of stock digests should
be made on the day of analysis.
8. Instrument Parameters
[0318] Startup will optimise the basic performance of the
instrument. The optimisation performed in Startup is applied to the
basic performance of the instrument. The optimisation specific to
the analysis is performed by the auto tune in each batch.
[0319] Example of instrument method parameters is detailed
below:
TABLE-US-00049 Parameter Value Acquisition Number of points per
mass 3 Replicates 3 Sweep 100 AutoTune On P/A factor adjustment On
Peristaltic Pump Before Acquisition Uptake Speed 0.30 rps Uptake
Time 60 sec Stabilisation Time 60 sec After Acquisition (Probe
Rinse) Rinse Speed 0.30 rps Rinse on rinse port (sample) 30 sec
Rinse on rinse port (STD) 30 sec After Acquisition (Rinse) Rinse
Vial 1 2 Rinse Speed 0.30 rps Rinse or rinse vial (Step 1) 60 sec
Rinse or rinse port (Step 1) 0 sec Rinse Vial 2 1 Rinse Speed 0.30
rps Rinse or rinse vial (Step 2) 30 sec Rinse or rinse port (Step
2) 0 sec Rinse Vial 3 1 Rinse Speed 0.20 rps Rinse or rinse vial
(Step 3) 30 sec Rinse or rinse port (Step 3) 0 sec Execute
Pre-emptive rinse Off Pre-emptive Time 0 sec Terminate a rinse step
at the end of Acq Off
9. Analysis
[0320] When performing analysis on unknown matrices it is
recommended that at least two isotopes of each element are selected
(if possible). Data is reported for the isotope based on the
following criteria. [0321] Free from polyatomic and isobaric
interference [0322] Best QC data [0323] Highest abundance
[0324] Perform the following typical injection sequence:
TABLE-US-00050 ICP-MS Wash X Cal Blank X Calibration Standards X
Wash X IQC standard X Wash X Samples (including duplicates) X
Spiked sample(s) X Wash X Check standard after 10 sample and end of
sequence X Wash X
[0325] The wash solution is an acid diluent made up to match the
acid concentration (or solvent) of the calibration blank. The
readings obtained for the wash solutions should be monitored to
ensure counts for the elements being tested are returning to their
background levels. If this is not the case, the sequence will need
to be restarted inserting additional washes as required to ensure
minimal carry over between test solutions. Minimal increases in the
background readings are allowed.
10. System Suitability--Acceptance Criteria
[0326] Reagent/process blank is to be run using the same
preparation methods as the sample to assess the background levels
of the reagents used for the sample preparation and contamination
from external sources. Results may not be reported <3 times the
blank concentration.
[0327] The RSD of each result reading of analyst and internal
standard should be <10%. An RSD above this value indicates poor
stability and indication of a possible problem with the instrument,
except at levels approaching zero.
[0328] The calibration graphs are assessed for linearity.
Calibrations should have a correlation coefficient
.gtoreq.0.998.
[0329] A calibration standard should be prepared at the required
quantitation/reporting limit if possible. The calculated
concentration, based on the calibration must be within 80-120% of
the expected concentration. (can be skipped if the limit is too
high to be included in the analysis, if there is no pre-defined
limit, or if the limit is for the collective concentrations of more
than one element e.g. total Hg, As and Cd<1 ppm).
[0330] A check calibration standard is run every 10 samples, and as
the final sample in the sequence, to ensure excessive drift does
not occur over the course of the run. The results should be between
85-115% of the expected value.
[0331] Results for IQC standards must be within 85-115% of the
expected (certified) value.
11. Calculations
[0332] Results in ppb: Calculate the concentration of the trace
elements using the following equation: Results(ppb)=Concentration
in test solution (ppb) x Dilution
12. Reporting
[0333] Trace Element Content: Report the results to 2 significant
figures
EQUIVALENTS
[0334] While several embodiments of the present invention have been
described and illustrated herein, those of ordinary skill in the
art will readily envision a variety of other means and/or
structures for performing the functions and/or obtaining the
results and/or one or more of the advantages described herein, and
each of such variations and/or modifications is deemed to be within
the scope of the present invention. More generally, those skilled
in the art will readily appreciate that all parameters, dimensions,
materials, and configurations described herein are meant to be
exemplary and that the actual parameters, dimensions, materials,
and/or configurations will depend upon the specific application or
applications for which the teachings of the present invention
is/are used. Those skilled in the art will recognize, or be able to
ascertain using no more than routine experimentation, many
equivalents to the specific embodiments of the invention described
herein. It is, therefore, to be understood that the foregoing
embodiments are presented by way of example only and that, within
the scope of the appended claims and equivalents thereto, the
invention may be practiced otherwise than as specifically described
and claimed. The present invention is directed to each individual
feature, system, article, material, kit, and/or method described
herein. In addition, any combination of two or more such features,
systems, articles, materials, kits, and/or methods, if such
features, systems, articles, materials, kits, and/or methods are
not mutually inconsistent, is included within the scope of the
present invention. In some embodiments, the term "about" as used
herein means+/-2%, 5%, or 10%. In some embodiments, the term
"substantially pure" as used herein means 99%, 98%, 95% or 90%
pure.
* * * * *