U.S. patent application number 16/277016 was filed with the patent office on 2019-11-14 for suspensions of cyclosporin a form 2.
The applicant listed for this patent is Allergan, Inc.. Invention is credited to E. Quinn Farnes, Anuradha V. Gore, Prem Swaroop Mohanty.
Application Number | 20190343917 16/277016 |
Document ID | / |
Family ID | 47278531 |
Filed Date | 2019-11-14 |
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United States Patent
Application |
20190343917 |
Kind Code |
A1 |
Gore; Anuradha V. ; et
al. |
November 14, 2019 |
SUSPENSIONS OF CYCLOSPORIN A FORM 2
Abstract
Disclosed herein are methods of formulating cyclosporin A Form
2.
Inventors: |
Gore; Anuradha V.; (Irvine,
CA) ; Mohanty; Prem Swaroop; (Irvine, CA) ;
Farnes; E. Quinn; (Laguna Beach, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Allergan, Inc. |
Irvine |
CA |
US |
|
|
Family ID: |
47278531 |
Appl. No.: |
16/277016 |
Filed: |
February 15, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14995868 |
Jan 14, 2016 |
10206971 |
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16277016 |
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14325167 |
Jul 7, 2014 |
9238002 |
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14995868 |
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13677014 |
Nov 14, 2012 |
8796222 |
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14325167 |
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61559866 |
Nov 15, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 9/0014 20130101;
A61P 27/02 20180101; A61K 47/26 20130101; A61K 38/13 20130101; A61K
9/14 20130101; A61K 47/06 20130101; A61P 27/14 20180101; C07K 7/645
20130101; A61K 9/0048 20130101; A61K 47/10 20130101 |
International
Class: |
A61K 38/13 20060101
A61K038/13; C07K 7/64 20060101 C07K007/64; A61K 9/00 20060101
A61K009/00; A61K 9/14 20060101 A61K009/14; A61K 47/10 20060101
A61K047/10; A61K 47/26 20060101 A61K047/26; A61K 47/06 20060101
A61K047/06 |
Claims
1. A nanosuspension formulation comprising particles of cyclosporin
A form 2 and a vehicle, wherein the average size (d90) of the
particles is less than about 10 .mu.m.
2. The formulation of claim 1, wherein the vehicle comprises at
least one surfactant and at least one stabilizer.
3. The formulation of claim 2, wherein cyclosporin is at a
concentration of about 0.01% to about 10%.
4. The formulation of claim 3, wherein the vehicle comprises one or
more surfactants selected from the group consisting of
polyoxyethylene (20) sorbitan monooleate, polyethylene glycol 660
hydroxystearate, polyoxyethylene (40) stearate Myrj 52, pluronic
F68, polyoxyethylene sorbitan monolaurate, and sodium
glycocholate.
5. The formulation of claim 3, wherein the vehicle comprises one or
more surfactants selected from the group consisting of
polyoxyethylene (20) sorbitan monooleate at a concentration of
about 0.1% to about 5% (w/v), polyethylene glycol 660
hydroxystearate at a concentration of about 0.1% to about 5% (w/v),
polyoxyethylene (40) stearate Myrj 52 at a concentration of about
0.1% to about 5% (w/v), pluronic F68 at a concentration of about
0.1% to about 5% (w/v), polyoxyethylene sorbitan monolaurate at a
concentration of about 0.1% to about 5% (w/v), and sodium
glycocholate at a concentration of about 0.1% to about 5%
(w/v).
6. The formulation of claim 4, wherein the vehicle comprises at
least one stabilizer selected from the group consisting of hydroxy
propyl cellulose, hydroxypropylmethyl cellulose,
hydroxyethylcellulose, polyvinyl pyrolidone, and
carboxymethylcellulose.
7. The formulation of claim 5, wherein the vehicle comprises one or
more stabilizers each selected from the group consisting of
hydroxypropyl cellulose at a concentration of about 0.1% to about
5% (w/v), hydroxypropylmethyl cellulose at a concentration of about
0.1% to about 5% (w/v), hydroxyethylcellulose at a concentration of
about 0.1% to about 5% (w/v), and polyvinyl pyrolidone at a
concentration of about 0.1% to about 5% (w/v), and
carboxymethylcellulose at a concentration of about 0.1% to about 5%
(w/v).
8. The formulation of claim 7, wherein the vehicle further
comprises one or more ingredients selected from glycerin, mannitol,
Pemulen TR-2, sodium citrate dihydrate, potassium chloride, boric
acid, sodium borate decahydrate, and water.
9. The formulation of claim 7, wherein the vehicle further
comprises one or more ingredients selected from glycerin at
concentration of about 1.0% to about 2.2%, mannitol at
concentration of about 0.5%, Pemulen TR-2 at concentration of about
0.01% to about 0.1%, sodium citrate dihydrate at concentration of
about 0.4%, potassium chloride at concentration of about 0.14%,
boric acid at concentration of about 0.25%, sodium borate
decahydrate at concentration of about 0.41%, and water.
10. The formulation of claim 1, wherein the average size of the
particles is less than about 1 .mu.m.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This patent application is a continuation of copending U.S.
patent application Ser. No. 14/995,868, filed Jan. 14, 2016, which
is a continuation of U.S. patent application Ser. No. 14/325,167,
filed Jul. 7, 2014, now issued as U.S. Pat. No. 9,238,002, which is
a divisional of U.S. patent application Ser. No. 13/677,014, filed
Nov. 14, 2012, now issued as U.S. Pat. No. 8,796,222, which claims
priority to U.S. Provisional Patent Application No. 61/559,866,
filed Nov. 15, 2011, the entire contents of which are hereby
incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates to the fields of nanotechnology and
drug formulation technology.
BACKGROUND
[0003] Cyclosporine A is the active ingredient in Restasis.RTM., a
drug that is used to treat dry eye disease. Cyclosporin A is poorly
soluble in water, and so is currently formulated either by
dissolving the drug in oil to form an emulsion, or by mixing the
drug with high levels of surfactants and/or solubilizers to form an
aqueous solution. The inventors have discovered a formulation of
cyclosporin A using a new crystalline polymorph of cyclosporin A,
to create nanosuspensions comprising particles of cyclosporin A
having an average size of around 1 micrometer or less (to put that
number in perspective, the average thickness of a human hair is
around 100 micrometers).
[0004] A nanosuspension of cyclosporin A, when delivered topically
to the eye, may have one or more advantages, including the
following: [0005] a higher bioavailability compared to suspensions,
due to the higher surface area available for dissolution; [0006] a
longer retention on the eye due to smaller particles, leading to
further improvement in bioavailability; [0007] a lower potential
for foreign body sensation or particle irritation, thus reducing
tearing and drainage of formulations from the eye; [0008] a lower
level of surfactants or solubilizers in the formulation, improving
tolerability and bioavailability of the drug.
BRIEF DESCRIPTION OF THE FIGURES
[0009] FIG. 1 shows the particle size distribution of cyclosporin A
Form 2 nanosuspensions prepared using a high pressure homogenizer
compared to suspensions prior to milling.
[0010] FIG. 2 compares the particle size distribution of
cyclosporin A Form 2 nanosuspensions prepared using different
surfactants and stabilizers.
[0011] FIG. 3 shows the particle size distribution of Formulation
diluted in vehicle containing Na CMC.
[0012] FIG. 4 shows average particle size of a nanosuspension using
cyclosporin A Form 3 compared to a nanosuspensions using Form 2
after milling using a microfluidizer. Form 2 Forms a nanosuspension
(particle size <1 .mu.m) while Form 3 does not.
[0013] FIGS. 5-13 show the results when four different formulations
according to the invention (summarized in Table 2) and
Restasis.RTM. are administered to NZW female rabbits (two rabbits
total, one formulation per eye) in a single topical dose:
[0014] FIG. 5 shows concentrations in the cornea.
[0015] FIG. 6 summarizes pharmacokinetic data.
[0016] FIG. 7 shows concentrations in the bulbar conjunctiva.
[0017] FIG. 8 shows concentrations in the palpebral
conjunctiva.
[0018] FIG. 9 summarizes pharmacokinetic data for the bulbar
conjunctiva and palpebral conjunctiva.
[0019] FIG. 10 shows concentrations in the bulbar conjunctiva.
[0020] FIG. 11 shows concentrations in the palpebral
conjunctiva.
[0021] FIG. 12 shows concentrations in the lacrimal gland.
[0022] FIG. 13 summarizes pharmacokinetic data for lacrimal
gland.
[0023] FIG. 14 depicts characteristic X-ray powder diffraction
(XRPD) patterns of CsA in a new crystalline form (designated as
Form 2 herein), tetragonal form (designated as Form 1 herein), and
orthorhombic form (designated as Form 3 herein).
[0024] FIG. 15 depicts the XRPD diffractogram of CsA crystalline
Form 2.
[0025] FIG. 16 depicts the water sorption/desorption profile of CsA
Form 2.
[0026] FIG. 17 depicts MDSC analysis of CsA Form 2 recovered from
0.04% formulation with 1% PS80.
[0027] FIG. 18 shows the simulated XRPD pattern of cyclosporine A
forms.
DETAILED DESCRIPTION
Cyclosporin A
[0028] Cyclosporin A (CsA) is a cyclic peptide having the following
chemical structure:
##STR00001##
Its chemical name is
cyclo[[(E)-(2S,3R,4R)-3-hydroxy-4-methyl-2-(methylamino)-6-octenoyl]-L-2--
aminobutyryl-N-methylglycyl-N-methyl-Lleucyl-L-valyl-N-methyl-L-leucyl-L-a-
lanyl-D-alanyl-N-methyl-L-leucyl-N-methyl-L-leucyl-Nmethyl-L-valyl].
It is also known by the names cyclosporine, cyclosporine A,
ciclosporin, and ciclosporin A. It is the active ingredient in
Restasis.RTM. (Allergan, Inc., Irvine, Calif.), an emulsion
comprising 0.05% (w/v) cyclosporin. Restasis.RTM. is approved in
the United States to increase tear production in patients whose
tear production is presumed to be suppressed due to ocular
inflammation associated with keratoconjunctivitis sicca.
Cyclosporin a Form 2
[0029] Cyclosporin A is known to exist in an amorphous form, liquid
crystal form, tetragonal crystalline form (form 1), and an
orthorhombic form (form 3). A new crystalline form, cyclosporin A
Form 2, has recently been discovered.
[0030] The XRPD pattern of CsA Form 2 differs significantly from
the tetragonal form and orthorhombic form (FIG. 14). The major
crystalline peaks for CsA form 2 appear at (2.theta.) when scanned
by an X-ray diffractometer with X-ray source as Cu K.alpha.
radiation, .lamda.=1.54 .ANG., at 30 kV/15 mA: 7.5, 8.8, 10.2,
11.3, 12.7, 13.8, 14.5, 15.6 and 17.5 (d-spacing in crystal lattice
at about 11.8, 10.0, 8.7, 7.8, 7.0, 6.4, 6.1, 5.6 and 5.1 .ANG.,
respectively, FIG. 15). These major peaks are defined as those
being unique to Form 2 relative to the orthorhombic or tetragonal
forms; as well as, peaks having an intensity greater than 5 times
the background.
[0031] In one embodiment, the new crystalline form (Form 2) of CsA
is a nonstoichiometric hydrate of Cyclosporin A. In another
embodiment, the crystalline Form 2 is represented by the
formula:
##STR00002##
wherein X is the number of molecules of water and varies from 0 to
3. In one embodiment, X in the above formula is 2.
[0032] Form 2 appears to be a kinetically stable form of CsA in
aqueous suspensions. Suspensions containing Form 2 show no
conversion to other known polymorphic or pseudomorphic forms upon
storage. It has been found that Form 1 and the amorphous form
convert to Form 2 in the presence of water.
[0033] The single crystal structure of the hydrate form of CsA Form
2 has been determined and the crystal structure parameters are
listed in Table 2. These results indicate that Form 2 is unique
compared to other known crystalline forms of cyclosporine A.
TABLE-US-00001 TABLE 1 Crystal data and data collection parameters
of crystal structure solution of CsA Form 2. formula
C.sub.52H.sub.115N.sub.11O.sub.14 formula weight 1238.67 space
group P 2.sub.1 2.sub.1 2.sub.1 (No. 19) a (.ANG.) 12.6390(5) b
(.ANG.) 19.7562(8) c (.ANG.) 29.266(2) volume (.ANG..sup.3)
7383.6(7) Z 4 d.sub.calc (g cm.sup.-3) 1.114 crystal dimensions
(mm) 0.27 .times. 0.16 .times. 0.12 temperature (K) 150 radiation
(wavelength in .ANG.) Cu K.sub.3 (1.54184) monochromator confocal
optics linear abs coef (mm.sup.-1) 0.640 absorption correction
applied empirical.sup.a transmission factors (min, max) 0.80, 0.93
diffractometer Rigaku RAPID-II h, k, l range -13 to 13 -21 to 21
-32 to 21 2.theta. range (deg) 5.38-115.00 mosaicity (deg) 1.31
programs used SHELXTL F.sub.0oo 2704.0 weighting
1/[.sigma..sup.2(Fo.sup.2) + (0.0645P).sup.2 + 0.0000P] where P =
(Fo.sup.2 + 2Fc.sup.2)/3 data collected 37360 unique data 9964
R.sub.int 0.077 data used in refinement 9964 cutoff used in
R-factor calculations F.sub.o.sup.2 > 2.0 s(F.sub.o.sup.2) data
with I > 2.0 s(l) 6597 number of variables 834 largest shift/esd
in final cycle 0.00 R(F.sub.o) 0.061 R.sub.w(F.sub.o.sup.2) 0.145
goodness of fit 1.037 absolute structure determination Flack
parameter.sup.b (0.0(3))
[0034] The asymmetric unit of this CsA Form 2 contains one
cyclosporine A molecule and two water molecules. It is possible
that any small molecule that can hydrogen bond to water could play
the role of space filler, which would give a range of potential
structures running from the orthorhombic dihydrate to distorted
monoclinic dihydrate The XRPD pattern calculated from the
single-crystal structure is shown in FIG. 8 and it matches the
experimental pattern shown in FIG. 2. These matching patterns
further corroborate that Form 2 is a unique and pure crystalline
form of cyclosporine A.
[0035] Without wishing to be bound by theory, thermogravimetric
analysis combined with KF titration and vapor sorption desorption
analysis (VSA) suggest that CsA Form 2 is a non-stoichiometric
hydrate of CsA. The vapor sorption analysis of Cyclosporine Form 2
indicates that water content in the new crystal form reversibly
varies with relative humidity as shown in FIG. 16. Similar to the
tetragonal form, the new CsA form undergoes a phase transition to a
liquid crystal or amorphous form at 124.4.degree. C. prior to
melting as indicated by the modulated differential calorimetric
(MDSC) analysis (FIG. 17).
[0036] Cyclosporin A Form 2 may be obtained by suspending amorphous
0.05% cyclosporin A (w/v) in 1% Polysorbate 80, heating the
solution to 65.degree. C., holding it at that temperature for 24
hours, and then recovering the precipitate by vacuum filtration.
One can then use the cyclosporin A Form 2 thus obtained to generate
additional amounts, using Cyclosporin A Form 2 as a seed crystal;
in this method, one suspends about 30 g cyclosporin A in a solution
of 900 ml water containing 1% (w/v) Polysorbate 80, heats the
solution to 65.degree. C., and then seeds it with 0.2 g of
cyclosporin A Form 2 at a temperature of 52.degree. C. The solution
is then stirred for about 22 hours at a temperature of between
about 61.degree. C. and 65.degree. C., and then recovers the
precipitate that results.
[0037] Further details regarding CsA Form 2 may be found in U.S.
patent application Ser. No. 13/480,710, the entire contents of
which are incorporated by reference herein.
Suspensions of Cyclosporin a Form 2
[0038] Compositions of the invention are ophthalmically acceptable
suspensions of Cyclosporin A form 2. By "ophthalmically
acceptable," the inventors mean that the suspensions are formulated
in such a way as to be non-irritating when administered to the eye
of a mammal, such as a human. In one embodiment, the compositions
are suspensions; that is, they comprise particles of cyclosporin A
form 2, having an average particle size greater than about 1 .mu.m,
dispersed throughout a liquid vehicle. In another embodiment, the
compositions are nanosuspensions; that is, they comprise particles
of cyclosporin A form 2, having an average particle size of less
than about 1 .mu.m, that are dispersed throughout a liquid
vehicle.
[0039] In one embodiment, the suspension comprises cyclosporin A
form 2 at a concentration of about 0.001% to about 10% (w/v). In
one embodiment, the suspension comprises cyclosporin A form 2 at a
concentration of about 0.001% (w/v) to about 0.01%, about 0.001%
(w/v) to about 0.04% (w/v), about 0.001% (w/v) to about 0.03%
(w/v), about 0.001% (w/v) to about 0.02% (w/v), or about 0.001%
(w/v) to about 0.01% (w/v). In another embodiment, the suspension
comprises cyclosporin A form 2 at a concentration of about 0.01%
(w/v) to about 0.05%, about 0.01% (w/v) to about 0.04% (w/v), about
0.01% (w/v) to about 0.03% (w/v), about 0.01% (w/v) to about 0.02%
(w/v), or about 0.01% (w/v) to about 0.01% (w/v). In another
embodiment, the suspension comprises cyclosporin A form 2 at a
concentration of about 0.01% (w/v) to about 0.1%, about 0.1% (w/v)
to about 0.5% (w/v), about 0.01% (w/v) to about 1% (w/v), or about
1% (w/v) to about 10%.
[0040] For example, the suspensions may comprise about 0.001%
(w/v), about 0.002% (w/v), about 0.003% (w/v), about 0.004% (w/v),
about 0.005% (w/v), about 0.006% (w/v), about 0.007% (w/v), about
0.008% (w/v), about 0.009% (w/v), about 0.01% (w/v), about 0.015%
(w/v), about 0.02% (w/v), about 0.025% (w/v), about 0.03% (w/v),
about 0.035% (w/v), about 0.04% (w/v), about 0.045% (w/v), about
0.05% (w/v), about 0.055% (w/v), about 0.06% (w/v), about 0.065%
(w/v), about 0.07% (w/v), about 0.075% (w/v), about 0.08% (w/v),
about 0.085% (w/v), about 0.09% (w/v), about 0.095% (w/v), about
0.1% (w/v), about 0.15% (w/v), about 0.2% (w/v), about 0.25% (w/v),
about 0.3% (w/v), about 0.35% (w/v), about 0.4% (w/v), about 0.45%
(w/v), about 0.5% (w/v), about 0.55% (w/v), about 0.6% (w/v), about
0.65% (w/v), about 0.7% (w/v), about 0.75% (w/v), about 0.8% (w/v),
about 0.85% (w/v), about 0.9% (w/v), about 0.95% (w/v), or about
1.0% (w/v) cyclosporin A form 2.
[0041] In one embodiment, the suspension comprises a surfactant. In
one embodiment, the surfactant is selected from polyoxyethylene
(20) sorbitan monooleate (Polysorbate 80), polyethylene glycol 660
hydroxystearate (Solutol), polyoxyethylene (40) stearate Myrj 52
(POE-40-Stearate), pluronic F68 (Polaxamer 188), polyoxyethylene
sorbitan monolaurate (Polysorbate 20), and sodium glycocholate
(NaGC). The vehicle may contain all of these surfactants, or one,
two, three, four, or five of them.
[0042] One can use between about 0.001% (w/v) and about 5% (w/v) of
the surfactant. In one embodiment, the suspensions contain about
0.001% (w/v) to about 1% (w/v), about 0.001% (w/v) to about 0.1%
(w/v), about 0.01% (w/v) to about 0.1% (w/v), or about 0.1% (w/v)
to about 1% (w/v) of the surfactant. For example, the suspensions
may contain about 0.001% (w/v), about 0.002% (w/v), about 0.003%
(w/v), about 0.004% (w/v), about 0.005% (w/v), about 0.006% (w/v),
about 0.007% (w/v), about 0.008% (w/v), about 0.009% (w/v), about
0.01% (w/v), about 0.02% (w/v), about 0.03% (w/v), about 0.04%
(w/v), about 0.05% (w/v), about 0.06% (w/v), about 0.07% (w/v),
about 0.08% (w/v), about 0.09% (w/v), about 0.1% (w/v), about 0.2%
(w/v), about 0.3% (w/v), about 0.4% (w/v), about 0.5% (w/v), about
0.6% (w/v), about 0.7% (w/v), about 0.8% (w/v), about 0.9% (w/v),
about 1% (w/v), about 2% (w/v), about 3% (w/v), about 4% (w/v), or
about 5% (w/v) of the surfactant.
[0043] When using more than one surfactant, the suspension may
contain the same or different amounts of each.
[0044] In addition to a surfactant, the suspensions may comprise a
stabilizer. In one embodiment, the stabilizer is selected from
hydroxy propyl cellulose, hydroxypropylmethyl cellulose,
hydroxyethylcellulose, polyvinyl pyrolidone,
carboxymethylcellulose, Pemulen.RTM., and Pemulen.RTM. TR-2.
Pemulen.RTM. is the trade name for high molecular weight,
crosslinked copolymers of acrylic acid and C10-C30 alkyl acrylate
produced by Lubrizol Corp. Pemulen.RTM. TR-2 is a C10-30 alkyl
acrylate crosspolymer containing a higher level of hydrophobic
groups than other Pemulen.RTM. polymers. The vehicle may contain
all of these stabilizers, or none of them, or it may contain one,
two, three, four, or five of them.
[0045] One can use between about 0.01% (w/v) and about 10% (w/v) of
the stabilizer. In one embodiment, the suspensions contain about
0.01% (w/v) to about 1% (w/v), or about 0.01% (w/v) to about 0.1%
(w/v), or about 0.1% (w/v) to about 1% (w/v) of the stabilizer. For
example, the suspensions may contain about 0.01% (w/v), about 0.02%
(w/v), about 0.03% (w/v), about 0.04% (w/v), about 0.05% (w/v),
about 0.06% (w/v), about 0.07% (w/v), about 0.08% (w/v), about
0.09% (w/v), about 0.1% (w/v), about 0.2% (w/v), about 0.3% (w/v),
about 0.4% (w/v), about 0.5% (w/v), about 0.6% (w/v), about 0.7%
(w/v), about 0.8% (w/v), about 0.9% (w/v), about 1% (w/v), about 2%
(w/v), about 3% (w/v), about 4% (w/v), about 5% (w/v), about 6%
(w/v), about 7% (w/v), about 8% (w/v), about 9% (w/v), or about 10%
of the stabilizer.
[0046] When using more than one surfactant, the suspension may
contain the same or different amounts of each.
[0047] In addition to a surfactant, the vehicle may also comprise a
tonicity adjustor selected from glycerin, mannitol, sodium citrate
dihydrate, potassium chloride, boric acid, and sodium borate
decahydrate. The tonicity adjustor is added as needed to achieve
the desired tonicity; the vehicle may contain all of these tonicity
adjusters, or none of them, or it may contain one, two, three,
four, or five of them. In one embodiment, the tonicity adjustors
are present in an amount of between about 0.1 (w/v) and about 10%
(w/v). When using more than one tonicity adjustor, the suspension
may contain the same or different amounts of each.
[0048] The suspension usually contains water, in an amount
sufficient to provide a desired pH, tonicity, and other
characteristics that would make the suspension appropriate for
administration to the eye.
Methods of Preparing Suspension of Cyclosporin a Form 2
[0049] The formulations of the invention may be made by mixing
cyclosporin A form 2 with the appropriate surfactants, stabilizers,
and tonicity adjustors, as described above, to form a suspension If
fine particles of cyclosporin A are desired, the suspension is then
milled using a high pressure homogenizer, such as those
commercially available from Microfluidics Intl Corp. of Newton,
Mass. A unique and surprising property of cyclosporin form A 2 is
that it may be milled, if desired, to obtain a suspension with an
average particle size (d90) of less than 1 .mu.m. The cyclosporin A
in such a nanosuspension has higher bioavailability compared to
other (macro) suspensions of cyclosporin A, due to the higher
surface area available for dissolution; bioavailability is further
enhanced because the smaller particles enable the Cyclosporin A to
be retained on the eye longer. The smaller particles of the
nanosuspensions result in a formulation with a lower potential to
produce a foreign body sensation or other irritation that a subject
perceives when the formulation is instilled in the eye. Also,
because the particles are smaller, they associate more readily with
surfactants and stabilizers, thereby permitting one to use lower
concentrations of them.
[0050] After the cyclosporin A form 2 suspension is milled, it is
diluted to obtain the final product.
Methods of Treatment
[0051] Compositions of the invention may be used to treat any
condition of the eye which is known to be amenable to topical
treatment with cyclosporin A (such as with Restasis.RTM.) at the
concentrations stated here. For example, compositions of the
invention may be used to treat patients suffering from dry eye, to
treat blepharitis and meibomian gland disease, to restore corneal
sensitivity that has been impaired due to refractive surgery on the
eye, to treat allergic conjunctivitis and atopic and vernal
keratoconjunctivitis, and to treat ptyregia, conjunctival and
corneal inflammation, keratoconjuntivitis, graft versus host
disease, post-transplant glaucoma, corneal transplants, mycotic
keratitis, Thygeson's superficial punctate keratitis, uveitis, and
Theodore's superior limbic keratoconjunctivitis, among other
conditions.
[0052] The International Dry Eye Workshop (DEWS) defines dry eye as
"a multifactorial disease of the tears and ocular surface that
results in symptoms of discomfort, visual disturbance, and tear
film instability with potential damage to the ocular surface,
accompanied by increased osmolarity of the tear film and
inflammation of the ocular surface." It includes those conditions,
such as keratoconjunctivitis sicca, that are caused by tear
deficiency or excessive evaporation of tears.
[0053] Blepharitis is a chronic disorder producing inflammation of
the anterior and posterior lid margin, with involvement of skin and
its related structures (hairs and sebaceous glands), the
mucocutaneous junction, and the meibomian glands. It can also
affect the conjunctiva, tear film, and the corneal surface in
advanced stages and may be associated with dry eye. Blepharitis is
commonly classified into anterior or posterior blepharitis, with
anterior affecting the lash bearing region of the lids, and
posterior primarily affecting the meibomian gland orifices.
[0054] Meibomian gland disease most often occurs as one of three
forms: primary meibomitis, secondary meibomitis, and meibomian
seborrhea. Meibomian seborrhea is characterized by excessive
meibomian secretion in the absence of inflammation (hypersecretory
meibomian gland disease). Primary meibomitis, by contrast, is
distinguished by stagnant and inspissated meibomian secretions
(obstructive hypersecretory meibomian gland disease). Secondary
meibomitis represents a localized inflammatory response in which
the meibomian glands are secondarily inflamed in a spotty fashion
from an anterior lid margin blepharitis.
[0055] Impaired corneal sensitivity often occurs after refractive
surgery, such as photorefractive keratectomy, laser assisted
sub-epithelium keratomileusis (LASEK), EPI-LASEK, customized
transepithelial non-contact ablation, or other procedures in which
the corneal nerves are severed. Impaired corneal sensitivity may
also occur after viral infection, such as by HSV-1, HSV-2, and VZV
viruses. Patients with impaired corneal sensitivity often complain
that their eyes feel dry, even though tear production and
evaporation may be normal, suggesting that "dryness" in such
patients is actually a form of corneal neuropathy that results when
corneal nerves are severed by surgery or inflamed after viral
infection.
[0056] Allergic conjunctivitis is an inflammation of the
conjunctiva resulting from hypersensitivity to one or more
allergens. It may be acute, intermittent, or chronic. It occurs
seasonally, that is, at only certain time of the year, or it occurs
perennially, that is, chronically throughout the year. Symptoms of
seasonal and perennial allergic conjunctivitis include, in addition
to inflammation of the conjunctiva, lacrimation, tearing,
conjunctival vascular dilation, itching, papillary hyperlasia,
chemosis, eyelid edema, and discharge from the eye. The discharge
may form a crust over the eyes after a night's sleep.
[0057] Atopic keratoconjunctivitis is a chronic, severe form of
allergic conjunctivitis that often leads to visual impairment.
Symptoms include itching, burning, pain, redness, foreign body
sensation, light sensitivity and blurry vision. There is often a
discharge, especially on awakening from a night's sleep; the
discharge may be stringy, ropy, and mucoid. The lower conjunctiva
is often more prominently affected than the upper conjunctiva. The
conjunctiva may range from pale, edematous, and featureless to
having the characteristics of advanced disease, including papillary
hypertrophy, subepithelial fibrosis, formix foreshortening,
trichiasis, entropion, and madurosis. In some patients the disease
progresses to punctate epithelial erosions, corneal
neovascularization, and other features of keratopathy which may
impair vision. There is typically goblet cell proliferation in the
conjunctiva, epithelial pseudotubular formation, and an increased
number of degranulating eosinophils and mast cells in the
epithelium. CD25+ T lymphocytes, macrophages, and dendritic cells
(HLA-DR.sup.+, HLA-CD1+) are significantly elevated in the
substantia propria.
[0058] Like atopic keratoconjunctivitis, vernal
keratoconjunctivitis is a severe form of allergic conjunctivitis,
but it tends to affect the upper conjunctiva more prominently than
the lower. It occurs in two forms. In the palpebral form, square,
hard, flattened, closely packed papillae are present; in the bulbar
(limbal) form, the circumcorneal conjunctiva becomes hypertrophied
and grayish. Both forms are often accompanied by a mucoid
discharge. Corneal epithelium loss may occur, accompanied by pain
and photophobia, as may central corneal plaques and Trantas'
dots.
EXAMPLES
[0059] The invention is further illustrated by the following
examples.
Example 1
[0060] The inventors prepared the following compositions:
TABLE-US-00002 TABLE 1 Formulations of cyclosporin A prepared in
Example 1 A B C D E F Ingredient Concentration % (w/v) CsA 0.01 to
0.05 Polysorbate 80 0.001 to 0.05 Glycerin 1 1.2 1.2 1 1.2 2.2
Mannitol 0.5 CMC 0.5 HEC 0.1-0.5 Pemulen TR-2 0.01-0.1 0.05-0.1
HPMC 0.1-1.0 PVP 0.1-10.0 Sodium Citrate 0.4 0.4 0.4 0.4 0.4
Dihydrate Potassium 0.14 Chloride Boric Acid 0.25 0.25 0.25 0.25
0.25 Sodium Borate 0.41 0.41 0.41 0.41 0.41 Decahydrate Purified
Water qs Qs qs qs qs Qs
[0061] The formulations of Table 1 were prepared by the following
process:
[0062] 1. Preparation of Concentrated Cyclosporin a Nanosuspensions
[0063] a. Cyclosporin A was mixed with an appropriate vehicle to
form a suspension. The concentration of Cyclosporin A in this
suspension is in the range of 1-10%. [0064] b. The cyclosporin A
suspension was milled using a high pressure homogenizer (a
Microfluidizer.RTM., manufactured by Microfluidics, Newton, Mass.)
or a ball mill to get nanosuspensions such that d90<11 Jm.
[0065] c. Vehicles used for preparation of nanosuspension
concentrate are as listed in Table 1
[0066] 2. Preparation of Final Product [0067] a. The concentrated
nanosuspensions prepared in Step-1 were diluted in vehicles
suitable for ophthalmic dosing to obtain final product at required
dose strength of cyclosporin A. Vehicles suitable for dilution may
contain buffers, stabilizers, gelling agents and/or dilution to
obtain final formulations with desired concentration of CsA. [0068]
b. Compositions of nanosuspension formulations prepared after
dilution of the nanosuspension concentrates are listed in Table
2,
[0069] Particle-size distribution of the different Formulations are
shown in FIGS. 1, 2, and 3.
[0070] FIG. 1 shows the particle size distribution of cyclosporin A
Form 2 nanosuspensions prepared using a high pressure homogenizer
compared to suspensions prior to milling.
[0071] FIG. 2 compares the particle size distribution of
cyclosporin A Form 2 nanosuspensions prepared using different
surfactants and stabilizers.
[0072] FIG. 3 shows the particle size distribution of Formulation
diluted in vehicle containing Na CMC (Table-2, vehicle A). Note
that no change in particle size is seen in the diluted Formulations
over 2 weeks as compared to the nanosuspension concentrate.
[0073] Average particle size of cyclosporin A Form 3 are shown in
FIG. 4. Cyclosporin A Form 2 Forms a nanosuspensions (particle size
<1 .mu.m) while Form 3 does not.
[0074] These experiments show that Form 2 consistently produced
nanosuspensions with lower particle size than any other crystalline
form of CsA. The smaller particle size of Form 2 nanosuspensions is
an advantage over other forms; among other reasons, it is expected
to show higher bioavailability due to larger surface area for
dissolution and longer retention in the eye, as well as improved
physical stability.
Example 2
[0075] The inventors prepared the cyclosporin A nanosuspensions
listed in Table 2, below:
TABLE-US-00003 TABLE 2 Formulations of cyclosporin A prepared in
Example 2 Restasis .RTM. A A1 B1 D Ingredient Concentration (% w/w)
Nano-suspension CsA -- 0.05 0.05 0.01 0.05 Polysorbate 80 -- 0.005
0.005 0.001 -- Na glychocholate -- -- -- -- from suspension Oil
Phase CsA 0.05 -- -- -- -- Castor oil 1.25 -- -- -- -- Aqueous
Vehicle PS80 1 0.045 0.045 0.049 0.05 Glycerin 2.2 2.2 2.2 2.2 2.2
Citric acid*H2O -- -- 0.007 -- -- Na2HPO4*7H2O -- -- 0.134 -- --
Pemulen TR-2 0.05 0.05 -- 0.05 0.05 Gellan Gum -- -- 0.6 -- --
Purified water QS QS QS QS QS
[0076] The inventors administered the above formulations to NZW
female rabbits (two rabbits total, one formulation per eye) in a
single topical dose. Results are summarized in FIGS. 5-13. They
show that formulation B1 delivers a 5-fold lower dose of
cyclosporin A (0.01% versus 0.05%) but maintains comparable cornea
exposure to 0.05% Restasis.RTM. as well as improves delivery to the
bulbar and palpebral conjunctiva.
* * * * *