U.S. patent application number 15/338051 was filed with the patent office on 2017-07-06 for phospholipid depot.
This patent application is currently assigned to Latitude Pharmaceuticals Inc.. The applicant listed for this patent is Andrew Xian Chen, Hailiang Chen. Invention is credited to Andrew Xian Chen, Hailiang Chen.
Application Number | 20170189532 15/338051 |
Document ID | / |
Family ID | 43541855 |
Filed Date | 2017-07-06 |
United States Patent
Application |
20170189532 |
Kind Code |
A1 |
Chen; Andrew Xian ; et
al. |
July 6, 2017 |
PHOSPHOLIPID DEPOT
Abstract
The present invention is directed to compositions and methods of
preparation of phospholipid depots that are injectable through a
fine needle.
Inventors: |
Chen; Andrew Xian; (San
Diego, CA) ; Chen; Hailiang; (San Diego, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chen; Andrew Xian
Chen; Hailiang |
San Diego
San Diego |
CA
CA |
US
US |
|
|
Assignee: |
Latitude Pharmaceuticals
Inc.
San Diego
CA
|
Family ID: |
43541855 |
Appl. No.: |
15/338051 |
Filed: |
October 28, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13523860 |
Jun 14, 2012 |
9517202 |
|
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15338051 |
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PCT/US2010/060964 |
Dec 17, 2010 |
|
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13523860 |
|
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61288220 |
Dec 18, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 47/28 20130101;
A61K 31/727 20130101; A61K 47/22 20130101; A61K 9/107 20130101;
A61K 47/02 20130101; A61K 47/44 20130101; A61K 31/546 20130101;
A61K 31/573 20130101; A61K 31/138 20130101; A61K 31/4174 20130101;
A61K 38/27 20130101; A61K 47/24 20130101; A61P 3/10 20180101; A61K
31/485 20130101; A61K 9/06 20130101; A61K 31/192 20130101; A61K
9/0019 20130101; A61K 38/215 20130101; A61K 47/20 20130101; A61K
31/445 20130101; C07K 2317/21 20130101; A61K 38/1816 20130101; A61K
38/28 20130101; A61K 9/1617 20130101; A61K 47/10 20130101; A61K
31/5513 20130101; A61K 47/26 20130101; C07K 16/241 20130101; A61K
31/337 20130101; A61K 31/167 20130101; A61K 31/519 20130101; A61K
38/26 20130101; A61P 17/00 20180101 |
International
Class: |
A61K 47/24 20060101
A61K047/24; A61K 9/00 20060101 A61K009/00; A61K 9/06 20060101
A61K009/06; A61K 47/44 20060101 A61K047/44; A61K 9/16 20060101
A61K009/16; A61K 47/28 20060101 A61K047/28; A61K 47/22 20060101
A61K047/22; A61K 47/26 20060101 A61K047/26; A61K 38/28 20060101
A61K038/28; A61K 47/18 20060101 A61K047/18; A61K 47/02 20060101
A61K047/02; A61K 47/10 20060101 A61K047/10; A61K 47/20 20060101
A61K047/20; A61K 31/485 20060101 A61K031/485; A61K 31/337 20060101
A61K031/337; A61K 31/167 20060101 A61K031/167; A61K 38/26 20060101
A61K038/26; A61K 38/21 20060101 A61K038/21; A61K 31/727 20060101
A61K031/727; A61K 38/18 20060101 A61K038/18; A61K 38/27 20060101
A61K038/27; C07K 16/24 20060101 C07K016/24; A61K 31/546 20060101
A61K031/546; A61K 31/445 20060101 A61K031/445; A61K 31/573 20060101
A61K031/573; A61K 31/192 20060101 A61K031/192; A61K 31/4174
20060101 A61K031/4174; A61K 31/519 20060101 A61K031/519; A61K
31/138 20060101 A61K031/138; A61K 31/5513 20060101 A61K031/5513;
A61K 9/107 20060101 A61K009/107 |
Claims
1. A nanoemulsion based injectable one-phase gel composition,
comprising: about 20% to about 60% by weight of a phospholipid
based on the total weight of the gel, wherein the phospholipid is a
member selected from the group consisting of a lecithin,
phosphatidylcholine or a mixture thereof; 0.1% to 65% by weight
water based on the total weight of the gel; 1% to 50% by weight of
an oil based on the total weight of the gel, wherein the
phospholipid comprising particles are stacked together and have a
size of less than 200 nm in diameter; wherein the composition has
an increased degree of order as shown by an increase in the
Scherrer crystalline domain size over a composition containing the
same quantities of the same components but prepared by a process
without forming a nanodispersion and the discrete phospholipid
particles; and is extrudable or injectable through a 25 G, 1/2 inch
long needle from a 1 cc syringe at an extrusion rate of 2 cc/min by
an applied force of no more than 12 pounds.
2. The gel composition of claim 1, further comprising a
pharmacologically active agent having concentration of no more than
20% by weight of the final gel composition.
3. The gel composition of claim 2, wherein the pharmacologically
active agent is a heat-sensitive pharmacologically active
agent.
4. The gel composition of claim 2, wherein the pharmacologically
active agent is a protein or peptide.
5. The gel composition of claim 2, wherein the pharmacologically
active agent is a member selected from the group consisting of an
insulin, an insulin analog, a crystalline insulin with zinc and/or
protamine, an NPH insulin, and a combination thereof.
6. The gel composition of claim 1, wherein the phospholipid
comprises 20% to 40% by weight based on the total weight of the
gel.
7. The gel composition of claim 1, wherein the phospholipid is a
lecithin.
8. The gel composition of claim 1, wherein the oil is selected from
the group consisting of a synthetic oil, a vegetable oil, a medium
chain oil, ethyl oleate, fatty acid, vitamin E, vitamin E
succinate, cholesterol, or a mixture thereof.
9. The gel composition of claim 1, further comprising one or more
sugars selected from the group consisting of sucrose, dextrose,
lactose, glucose, trehalose, maltose, mannitol, sorbitol, glycerol,
amylose, starch, amylopectin, or a mixture thereof.
10. The gel composition of claim 1, further comprising one or more
non-aqueous solvents selected from the group consisting of ethanol,
propylene glycol, glycerol, sorbitol, polyethylene glycol, ethyl
oleate, or a mixture thereof.
11. The gel composition of claim 1, further comprising a functional
pharmaceutical excipient selected from the group consisting of an
acidifying agent, an alkalizing agent, a pH buffering agent, a
metal ion chelator, an antioxidant, a preservative, a
tonicity/osmotic pressure modifier, a condensing agent, a
solubilizing agent, or a mixture thereof.
12. The gel composition of claim 1, wherein the gel composition has
a small-angle X-ray scattering diffractogram of FIG. 10 and a
lattice d spacing of 67 .ANG. and 33 .ANG..
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 13/523,860 filed Jun. 14, 2012, issued on Dec.
13, 2016 under U.S. Pat. No. 9,517,202 B2, which application is a
continuation of PCT/US2010/060964, filed Dec. 17, 2010, which
application claims priority to U.S. Provisional Patent Application
No. 61/288,220, filed Dec. 18, 2009, the teachings of all of which
are hereby incorporated by reference in their entireties for all
purposes.
FIELD OF THE INVENTION
[0002] The present invention relates to phospholipid depot
compositions for insulin and other drugs and methods for
preparation.
BACKGROUND OF THE INVENTION
[0003] An injectable depot is designed to prolong the duration of
action and reduced the frequency of injection for a drug. Such
depots are generally administered by subcutaneous or intramuscular
injection or by injection or instillation into body tissues,
vessels or cavities. A depot prolongs the action of a
pharmacologically active agent by releasing it into surrounding
tissues from a reservoir slowly over time. A 1-day, 7-day or 30-day
depot release profile, which enables a once-a-day, once-a-week or
once-a-month injection schedule, respectively, would be highly
desirable for convenience and better patient compliance.
[0004] Various materials have been employed for depot compositions.
The most common depot-forming materials are biodegradable synthetic
polymers, e.g., polylactic-co-glycolic acid (PLGA) and polylactic
acid (PLA). The biodegradable polymer depot generally comes in two
common forms: microcapsules/microspheres and polymer gels. The
PLGA/PLA depots have been used in several FDA approved drugs i.e.,
Zoladex.TM. (goserelin acetate) and Lupron Depot.TM. (leuprolide
acetate), which are PLGA microcapsules and microsphere,
respectively. Eligard.TM. is in a polymer gel made by dissolving a
drug and PLGA in a strong organic solvent i.e.,
N-methyl-2-pyrrolidone.
[0005] A major disadvantage of the polymer depots is that they
require large diameter needles for injection or implantation due to
the physical size of the microcapsules/microspheres and/or the high
viscosity of the polymer gel. For example, 14- or 16-gauge (G)
needles are required for implantation of Zoladex.TM. and 18 G or 20
G needles for injection of Eligard.TM.. However, in common medical
practice, needles of size greater than 21 G are generally not used
for injection because they cause significant pain and psychological
trauma for patients. For drugs like insulin, which are
self-administered daily, fine 25-27 G needles and 1 cc syringes are
used. The injectability or ease with which the end user can
self-inject through such a system will be key to such a drug's user
compliance and therapeutic efficacy. For discussion purposes
herein, the injectability of a syringe-administered depot is
quantitatively defined as meeting the "Acceptable Injectability
Criterion" if it requires an applied force of no more than 10
pounds to be extruded from a 1 cc syringe through a 25 G 1/2 inch
long needle at rate of 2 cc/min. Such a scenario represents typical
conditions during the self-administration of insulin and other
self-injected drugs.
[0006] Moreover, PLGA and PLA are insoluble in water and both
require extremely strong organic solvents such as methylene
chloride, chloroform or N-methyl-2-pyrrolidone to fabricate the
microcapsules/microspheres or gels. Unfortunately, most biological
molecules such as protein drugs are incompatible with strong
solvents. Methylene chloride or N-methyl-2-pyrrolidone, which are
used in PLGA/PLA production, denature insulin immediately upon
contact.
[0007] Phospholipids (PL) are naturally occurring substances in the
human body and are the major constituents of cell membranes. These
molecules have an established record of safety and biocompatibility
as components in injected medicines. PL are also generally
insoluble in water (like the PLGA polymers) and following injection
into tissue and coming into contact with aqueous body fluids and
tissues, PL can precipitate and trap a co-administered drug, to
form a drug-PL co-precipitate that can function as a depot. Over
time, this mass diffuses slowly into a surrounding tissue and/or is
degraded by phospholipase, which is an enzyme distributed
throughout the body that slowly hydrolyzes phospholipids, resulting
in a slow release of the trapped drug. With such favorable safety,
solubility and biocompatibility properties, it would appear that
phospholipids are ideal depot materials. However, to date, there
has been few successful depot drug product based on phospholipids.
One primary problem is the poor injectability associated with
phospholipid-based compositions.
[0008] This inventor has discovered that a high concentration
(i.e., 20-80%) of phospholipids is generally required in order to
form the mass that permits depot functionality. However, once the
phospholipid concentration exceeds about 20% in a composition, the
composition becomes thick, viscous and difficult to inject through
fine needles without using an excessively high force. For example,
Phosal 50PG, Phosal 50SA, and Phosal 50MCT (produced by the America
Lecithin Company) are liposome-forming compositions containing
about 50% phospholipids dissolved in propylene glycol/ethanol, oil,
and medium chain oil, respectively. With their honey-like
consistency, the Phosal compositions are very difficult to inject
using a conventional hypodermic needle and syringe. It requires
more than 20 pounds of force to extrude Phosal through a 25 G V2
inch long needle from a 1 cc syringe at a plunger speed of 2
cc/min. Thus, it will take 2-5 minutes or more to manually extrude
1 mL of the Phosal-based depot through a 26 G needle even using a
very high force--which is impractical for general medical use and
definitely not suitable for self-administration. Therefore,
acceptable injectability using fine hyperdermic needles has been a
main reason preventing phospholipids from becoming useful depot
materials. This invention discloses phospholipid depots with
surprisingly good injectability that meets the Acceptable
Injectability Criterion, as defined above.
[0009] Another difficulty working with phospholipids is that
phospholipids are only soluble in certain organic solvents (e.g.,
ethanol) or oil (e.g., vegetable oil) and many drugs (such as
insulin or other protein drugs) are only soluble and stable in
water, but not soluble or stable in solvents or oils that can
dissolve phospholipids. Therefore, it has been impossible to
manufacture phospholipid-based depots using conventional solvent
methods or other methods disclosed in prior art without having the
solvent-sensitive drugs precipitate or degrade (See WO 2006/002050,
U.S. Pat. No. 5,807,573, WO/1994/008623, U.S. Pat. No. 5,004,611
and Harry Tiemesseen, et al. (2004) European Journal of
Pharmaceutics and Biopharmaceutics Volume 58 (2005), pp
587-593).
[0010] Another hurdle in the production of phospholipid depots
relates to difficulty in preparing a depot suitable for injection
under sterile conditions. Many drugs are heat-sensitive and cannot
survive heat sterilization (e.g., autoclaving) or radiation
sterilization. This is especially true for biological drugs such as
insulin and other protein drugs. In many cases, the only practical
way to sterilize a protein-containing composition is by filtration
through a 0.2- or 0.45-micron pore membrane to remove any microbial
contaminants. With a 20-80% phospholipid content, the thick
consistency of the depot compositions precludes any possibility of
sterilization by filtration. Therefore, this invention also teaches
unique methods for preparing depots that may be sterilized by
filtration.
[0011] Insulin is the mainstay for treatment of virtually all type
1 and many type 2 diabetic patients. Insulins and insulin
formulations are divided into two types: (1) quick onset/short
acting and (2) long-acting. The first type ("preprandial") is used
to control transient elevated blood glucose levels that occur after
meals. Long-acting insulin is used to maintain a controlled
baseline level of glucose level over a long duration such as 12-24
hours. A long-acting insulin or insulin formulation is thus
referred to as "basal insulin"
[0012] Basal insulin therapy is utilized to achieve "glycemic
control," which is the maintenance of blood glucose levels at a
constant and acceptable level without fluctuations. Sufficient
glycemic control requires plasma glucose levels to be maintained
within normal limits (70-130 mg/dl, or 3.9-7.2 mmol/L) and
indistinguishable from that in a non-diabetic person. Glucose level
fluctuations, especially the high peaks and valleys resulting from
poor glycemic control, are high risk factors for
diabetes-associated complications that can lead to morbidity and
mortality. Therefore, to achieve adequate glycemic control, an
ideal basal insulin formulation should deliver insulin to the
circulation at a constant rate (i.e., peak-less) over a prolonged
period of time, such as 24 hours. Human insulin itself has a rapid
onset and short duration of action (the half-life of insulin is
only about 5-6 minutes in the circulation). Therefore, a human
insulin depot formulation requires an approach that is capable of
both sequestering and releasing it slowly and constantly to address
the requirements needed for a successful basal insulin therapy.
[0013] The pharmacological efficacy of insulin can be readily
monitored by following the post-administration plasma glucose
concentration-time profile and the plasma insulin
concentration-time profile. The former measures insulin's
glucose-lowering efficacy or the pharmacodynamic or PD profile and
the latter measures the insulin plasma levels as a pharmacokinetic
or PK profile.
[0014] The currently available basal human insulin formulations in
the US include the NPH (Neutral Protamine Hagedorn) insulin sold
under the trade names of Humulin N and Novolin N by Eli Lilly and
Company and Novo Nordisk, respectively. NPH insulin, which was
invented in the 1930's by Hans Christian Hagedorn, is a suspension
of zinc-insulin crystalline complexes combined with the positively
charged polypeptide, protamine. The complexation with zinc and
protamine turns the insulin into insoluble particles after
injection that slowly release insulin.
[0015] Despite its long history of use (over 70 years), NPH is not
an ideal depot formulation for basal insulin therapy. The following
shortcomings are well known: [0016] High C.sub.max: The NPH PK
profile has a pronounced peak or C.sub.min. that occurs in about 4
hours after subcutaneous injection. This high C.sub.max causes
hypoglcermia. Since basal insulin is typically given at bedtime,
the 4 hr post-injection hypoglycemic phase normally occurs when the
patient is asleep. However, if the patient were to awaken in the
middle of the night and get out of bed, the hypoglycemic episode
could lead to fainting. [0017] Short duration of action: NPH
releases a substantial amount of its insulin within the first few
hours and is depleted in about 14-16 hours, making it suitable only
as a twice-a-day (BID) formulation. This deficiency disqualifies
NPH as a true, once-a-day (QD) formulation. [0018] High
peak-to-valley ratio of plasma insulin: In clinical practice, BID
regimens for NPH are still unable to stem high C.sub.max (peak) and
low C.sub.min (valley) fluctuations. The resulting sub-optimal
glycemic control increases the risk for diabetic complications.
[0019] Poor dose uniformity: For suspensions like NPH, an intrinsic
problem is the inability to achieve uniform injection-to-injection
dosing in a small volumes--even with strict adherence to the
rigorous pre-injection mixing/shaking instructions. For NPH this
difficulty is further compounded because it is typically injected
in very small volumes (<1 mL). Thus, the variability with
respect to the amount of insulin injected dose-to-dose for NPH can
be as high as 10-20%, which also contributes to poor glycemic
control.
[0020] More recently, two basal insulin drugs, LANTUS.RTM. (insulin
glargine, Sanofi-aventis) and LEVEMIR.RTM. (insulin detemir, Novo
Nordisk), were developed and subsequently approved. Both
LANTUS.RTM. and LEVEMIR.RTM. are insulin analogs, in that they are
chemically modified insulin and are not the authentic human insulin
molecule. In contrast to NPH, LANTUS.RTM. releases insulin in a
"peak-less" (peak to trough ratio less than 5 within 24 hours after
each injection) PK profile over 24 hours, which are key factors
underlying the drug's applicability as a once-a-day dose and its
achievement of better glycemic control. Compared to NPH,
LEVEMIR.RTM. has a less spiky PK profile but its duration of action
is somewhat similar to NPH, making it suitable only for BID dosing.
Of these two basal insulin analogs, LANTUS.RTM. has clear
advantages over NPH owing to its 24 hr peak-less insulin PK
profile.
[0021] Recently, LANTUS.RTM. has been reportedly linked to certain
cancers. The FDA noted: "3 of 4 observational studies suggest an
increased risk for cancer associated with use of Lantus." (Pink
Sheet, Jul. 6, 2009, p. 30). LANTUS.RTM. is also associated with a
high incidence of injection site pain possibly due to its low pH
formulation (pH 4). Unlike human insulin, the long-term safety of
the insulin analogs are unclear.
[0022] Despite the recent advances for insulin drugs, there is a
need for improved basal insulin formulations that provide a 24 hr
peak-less PK profile. Moreover, there remains a need for a
phospholipid depot suitable for injection under sterile conditions.
A method is needed to enable a water-soluble or
solvent-incompatible drug to be incorporated into a phospholipid
depot. The present invention satisfies these and other needs.
BRIEF SUMMARY OF THE INVENTION
[0023] The present invention provides compositions and methods for
preparing phospholipid depots that are injectable through a fine
needle. Advantageously, the gels are easily injectable through a
fine needle even though they preferably have a high phospholipid
content (e.g., 20-80%). The inventive gels are substantially
uniform or one-phase, i.e., the pharmacologically active agent is
uniformly distributed and remains uniformly distributed throughout
the gel matrix, even after centrifugation at 1000 RPM for 5
minutes. This invention also relates to unique methods for the
preparation of depots that allow for the intimate mixing or
incorporation of water-soluble or solvent-incompatible drugs into
phospholipid depots.
[0024] As such, in one embodiment, the present invention provides a
one-phase gel composition, comprising:
[0025] 20 to 80% by weight of one or more phospholipids;
[0026] optionally a pharmacologically active agent; and
[0027] 0.1 to 70% by weight water, wherein the gel composition is
extrudable through a 25 G 1/2 inch long needle from a 1 cc syringe
at an extrusion rate of 2 cc/min by an applied force of no more
than 12 pounds. The phospholipid depots are one-phase gels that can
be aqueous or substantially anhydrous. In preferred embodiments,
the formulation contains about 1 to about 20% pharmacologically
active agent. In one embodiment, the optional pharmaceutical active
ingredient is absent or not present and the gel is useful as a
dermal filler.
[0028] In yet another embodiment, the present invention provides a
method for preparing a one-phase gel composition, comprising:
[0029] a) forming a primary dispersion comprising one or more
phospholipid(s) and an excessive amount of water;
[0030] b) homogenizing the primary dispersion to form a
nanodispersion with an average particle size of about 30 nm to
about 200 nm in diameter;
[0031] c) optionally passing the nanodispersion through a 0.2- or
0.45-micron filter; and
[0032] d) removing the excessive water to obtain a one-phase gel
composition.
[0033] In certain embodiments, the one-phase gel is an aqueous gel.
In other embodiments, the one-phase gel is substantially an
anhydrous gel. In certain embodiments, the one-phase gel further
comprises a pharmacologically active agent. When a
pharmacologically active agent is present, it may be is added
before step "b" or it may be added after step "b." In other
embodiments, it may be added before as well as after step "b."
[0034] In other embodiments, the present invention provides a
one-phase aqueous gel made by methods herein. The gel can be
aqueous or a substantially anhydrous gel made by methods
herein.
[0035] In certain embodiments, the aqueous or substantially
anhydrous gels are transparent in appearance and silky smooth to
the touch. Theologically, the inventive gels are shear thinning and
thixotropic, which are desired properties for good
extrudability/injectability through a fine needle. In contrast, the
same compositions, when prepared by known prior art methods, result
in thick pastes that are very difficult or impossible to inject
through a fine hypodermic needle.
[0036] These and other aspects, objects and embodiments will become
more apparent when read with the accompanying detailed description
and the figures that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIGS. 1A-1C show three translucent aqueous gels. FIG. 1A:
aqueous gel (T-5) contains 37% water, but has no pharmacologically
active agent in the T-5 composition as in EXAMPLE 1. FIG. 1B and
FIG. 1C: aqueous gels each containing 100 unit/mL recombinant human
insulin and 50% water but made with soy lecithin (FIG. 1B) or a
synthetic phospholipid (POPC) (FIG. 1C), both as in EXAMPLE 3.
[0038] FIG. 2 illustrates pharmacokinetic profile in dogs following
a subcutaneous (SC) or intramuscular injection (IM) at 0.25 mg/kg
dose of buprenorphine in an anhydrous gel (F-27 as in EXAMPLE
6).
[0039] FIG. 3 illustrates prolonged local analgesic/anesthetic
efficacy of lidocaine in an anhydrous gel (F-20 as in EXAMPLE 8) in
guinea pigs following an intracutaneous injection compared to
placebo anhydrous gel.
[0040] FIG. 4 shows difference in injectability through 27 G
needles after 5-second manual extrusion using 1 mL syringes between
two phospholipid preparations containing the same composition (T-4)
as in EXAMPLE 1 but prepared by different methods. The clear gel is
an anhydrous gel (in top syringe) and was prepared according to the
method in EXAMPLE 1 and the opaque gel (bottom syringe) was
prepared by the method taught in other prior arts wherein all
components were mixed and homogenized. After applying the same
force and duration to the syringes, substantially more aqueous gel
was ejected, compared to the opaque paste prepared according to
other existing methods.
[0041] FIG. 5 illustrates the superior uniformity and physical
stability of an aqueous gel produced using the methods of the
present invention (right, T-4 as in EXAMPLE 1) compared to a paste
produced by mixing the same components but using a different
process than the aqueous gel (left). After centrifugation (13,000
rpm, 10 minutes), the paste separates into liquid and solid phases
whereas the aqueous gel remains as a uniform, single-phase gel.
[0042] FIGS. 6A-6B. show a representative injection force versus
time profile for the insulin-containing aqueous gel (F-43) in
EXAMPLE 14 (upper panel). The test measured the force necessary to
eject the gel from a 1 cc syringe through a 25 G 1/2 inch long
needle at rate of 2 cc/min. For comparison, the force profile for
glycerin is shown in the lower panel. With a maximum injection
force of less than 1.25 pounds, F-43 can be regarded as very
injectable. Even as a gel, it was much easier to inject than the
liquid glycerin, which required approximately 8 pounds of
force.
[0043] FIG. 7 shows blood glucose levels following a subcutaneous
injection of a 20 IU/kg insulin dose for four different basal
insulin formulations in the streptozotosin (STZ)-induced type-I
diabetic Sprague Dawley rat animal model. Data points are mean
values from 3 rats and error bars represent the standard error of
the mean.
[0044] FIGS. 8A-8B show the plasma insulin levels (upper panel)
measured using a human insulin ELISA kit and the blood glucose
levels (lower panel) measured by a glucometer following
subcutaneous injection of two different basal insulin formulations
in the streptozotosin (STZ)-induced type-I diabetic Sprague Dawley
rats. Data points are mean values from 4 rats and error bars
represent the standard error of the mean.
[0045] FIG. 9 is a schematic representation of the speculated
conversion from a nanodispersion (left) to a PG (right) upon
removal of water. The circles depict the nanosized phospholipid
particles in the nanodispersion, and the space between the dots are
filled with water as in an aqueous gel or oil as in an anhydrous
gel.
[0046] FIG. 10 shows SAXS diffractograms for F-43 PG prepared
according to the method disclosed in the present invention ("F-43
PG according to the present invention") and the same composition as
F-43, but prepared by direct mixing ("Same composition by other
method").
DETAILED DESCRIPTION OF THE INVENTION
I. Definitions
[0047] The phrase "Acceptable Injectability Criterion" as used
herein includes quantitatively defining a formulation that requires
an applied force of no more than 10 pounds to extrude the
formulation from a 1 cc syringe through a 25 G 1/2 inch long needle
at rate of 2 cc/min. In certain instances, the applied force is not
more than 6 pounds, 7 pounds, 8 pounds, 9 pounds, 10 pounds, 10.5
pounds, 11 pounds, 12 pounds, 13 pounds, 14 pounds, 15 pounds, 16
pounds, 17 pounds, 18 pounds, 19 pounds or 20 pounds, to extrude
the formulation from a 1 cc syringe through a 25 G .sup.1/.sub.2
inch long needle at rate of 2 cc/min. Such a scenario represents
typical conditions during the self-administration of insulin and
other self-injected drugs.
[0048] The term "acidifying agent" includes a pharmaceutically
acceptable acid such as hydrochloric acid, acetic acid, and
sulfuric acid, and the like.
[0049] As used herein, the term "alkalizing agent" includes a
pharmaceutically acceptable base such as sodium hydroxide,
potassium hydroxide, ammonium hydroxide, lysine, arginine, and the
like.
[0050] As used herein, the term "antimicrobial preservative"
includes a pharmaceutical additive that can be added to an
injectable pharmacologically active agent and be used to inhibit
the growth of bacteria and fungi. The antimicrobial preservatives
useful in this invention include, but are not limited to, cresols,
phenol, benzyl alcohol, ethanol, chlorobutanol, parabens, imidura,
benzylkonium chloride.
[0051] As used herein, the term "antioxidant" includes primarily
reducing agents. The reducing agents useful in this invention
include, but are not limited to, ascorbic acid or salts thereof,
ascorbyl palmitate, sodium metabisulfite, propyl gallate, butylated
hydroxyanisole, butylated hydroxytoluene, tocopherol, methionine or
salts thereof, citric acid or salts thereof, reducing sugars, or
mixtures thereof.
[0052] As used herein, the term "aqueous phase" includes a water
solution containing pharmaceutically acceptable additives, such as
acidifying, alkalizing, pH buffering, chelating, condensing and
solubilizing agents, antioxidants and antimicrobial preservatives,
tonicity/osmotic modifying agent, other biocompatible materials or
therapeutic agents. In certain embodiments, such additives assist
in stabilizing the pharmacologically active agent and depot
compositions and in rendering the compositions biocompatible.
[0053] As used herein, the term "condensing agent" includes a
pharmaceutically acceptable chemical that reduces solubility,
alters release rate or increases stability of the pharmacologically
active agent. For example, zinc ion forms insoluble crystals of
with insulin and causes the insulin to release slowly. Other
examples may include aluminum ions, ferric ions, protamine, or the
like.
[0054] As used herein, the term "depot" includes a
pharmacologically active agent delivery composition that is capable
for releasing the pharmacologically active agent in a slow or
controlled manner into the surrounding tissues to achieve a
prolonged duration of action in comparison with the
pharmacologically active agent without such composition. A depot
composition may be administered by injection, instillation, or
implantation into soft tissues, a certain body cavity or
occasionally into a blood vessel with injection through fine
needles being the preferred method of administration. A depot of
pharmacologically active agent is intended to provide (1)
convenient or less frequent dosing, (2) prolonged action, (3)
improved safety and/or (4) better drug efficacy. The term "depot
composition" can be used interchangeably with "sustained-release
composition," "slow-release composition," "timed-release
composition," "extended-release composition," "delayed-release
composition," "long-acting composition," or "controlled-release
composition."
[0055] As used herein, the term "emulsion" includes a mixture of
immiscible oil phase and aqueous phase, where the oil phase
comprises the oil and phospholipids and is in form of small
droplets (the dispersed phase), which are suspended or dispersed in
the aqueous phase (continuous phase). The primary emulsion formed
in accordance with the present invention is typically optically
opaque and possesses a finite stability.
[0056] As used herein, the term "a fine hypodermic needle" includes
a small-diameter, hollow needle that is used with a syringe to
inject substances into the body. The outer diameter of the needle
is indicated by the needle gauge system. According to the Stubs
Needle Gauge system, hypodermic needles in common medical use range
from 7 gauge (the largest) to 33 (the smallest). The word "fine,"
as used herein, includes needles ranging from 21 to 33 gauge (G),
preferably 25 G to 31 G and most preferably 25 G to 29 G. The
definition for the fine hypodermic needle applies to both re-usable
and disposable types. Disposable needles can be embedded in a
plastic or aluminum hub that attaches to the syringe barrel by
means of a press-fit or twist-on fitting or the "Luer Lock"
connections or be permanently attached to the syringe barrel.
[0057] As used herein, the term "heat-sensitive pharmacologically
active agent" includes a pharmacologically active agent that can
lose 3% or more of its potency or concentration after autoclave
treatment such as at 121.degree. C. for 15-20 min. Some chemical
drugs and many biological drugs are heat-sensitive. For these
drugs, terminal sterilization procedures that use heat (or
autoclaving) are not feasible.
[0058] As used herein, the term "injectable or extrudable" includes
meeting the Acceptable Injectability Criterion as previously
defined above.
[0059] As used herein, the term "insulin" includes a peptide
hormone that is central to regulating carbohydrate and fat
metabolism in the body, comprised of 51 amino acids and may be
derived from various animal sources including bovine and porcine
insulin or made by recombinant technology. The preferred insulin is
a recombinant human insulin.
[0060] As used herein, the term "insulin analog" includes a
chemically or enzymatically modified insulin wherein certain
alteration is made to the peptide sequence or amino acid side
chains in order to alter the pharmacodynamic or pharmacokinetic
property of the insulin. The preferred insulin analogs include
insulin lispro, insulin aspart, insulin glulisine, insulin
glargine, and insulin detemir The more preferred insulin analog is
insulin glargine or insulin detemir.
[0061] In accordance with the practice of the present invention,
lecithins used herein include pharmaceutical grade lecithins
derived from egg or soybean, which have been used in parenteral
products and are substantially free from irritating, allergenic,
inflammatory agents or agents that cause other deleterious
biological reactions. Other examples of phospholipids from
naturally occurring sources that may be used for this invention
include sphingolipids in the form of sphingosine and derivatives
(obtained from soybean, egg, brain & milk), gangliosides, and
phytosphingosine and derivatives (obtained from yeast).
[0062] As used herein, the term "metal ion chelating agent or
chelator" includes a metal ion chelator that is safe to use in an
injectable product. A metal ion chelator works by binding to metal
ions and thereby reduces the catalytic effect of metal ion on the
oxidation, hydrolysis or other degradation reactions. Metal
chelators that are useful in this invention may include disodium
edetate (EDTA), glycine and citric acid and the respective salts
thereof.
[0063] As used herein, the term "nanodispersion" includes an
emulsion or suspension formed by a homogenization step in the
process for PG's. A nanodispersion of this invention contains
phospholipid particles or oil droplets of a size less than 200 nm,
preferably less than 100 nm and most preferably less than 50 nm. A
nanodispersion may be referred to as a "nanoemulsion" if oil is
present or "nanosuspension" if oil is not present in the
composition.
[0064] As used herein, the term "nanodispersion" includes a
suspension or emulsion with with an average particle diameter of
about 5 nm to about 200 nm, preferably about 5 nm to about 100 nm
and more preferably about 5 nm to about 50 nm.
[0065] As used herein, the term "NPH insulin," or NPH includes
Neutral Protamine Hagedorn (also known as Humulin N, Novolin N,
Novolin NPH, NPH Lletin II, and insulin isophane) NPH is a
suspension of crystalline zinc insulin combined with the positively
charged polypeptide, protamine and was created in 1936 when Nordisk
formulated "isophane" insulin by adding Neutral Protamine to
regular insulin. NPH insulin used herein also includes other
insoluble insulin particles formed with zinc and/or protamine in
ratios that are different from the insulin isophane.
[0066] As used herein, the term "oil" includes oil in a general
sense to identify hydrocarbon derivatives, carbohydrate
derivatives, or similar organic compounds that are liquid at body
temperatures, e.g., about 37.degree. C., and are pharmacologically
acceptable in injectable formulations. "Oil" includes natural or
synthetic glycerides or non-glycerides comprising synthetic
triglycerides such as tricaprylin, triolein, or trimyristin,
vegetable oil, animal oil, medium chain oil/glycerides, vitamin E,
vitamin E acetate, vitamin E succinate, fatty acid, fatty acid
monoester, cholesterol, and the like.
[0067] The term "one-phase" as used herein includes the ability of
a PG to maintain a substantially uniform content for its key
component, i.e., the pharmacologically active agent being uniformly
distributed throughout the gel matrix, even after centrifugation at
1000 RPM for 5 minutes. In one aspect, a formulation that is one
phase is "substantially uniform" wherein concentration of the
pharmaceutically active agent in the different samples collected
throughout a gel in a syringe or a bulk has a coefficient of
variation (CV) less than about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%
or 10%.
[0068] The term "Phospholipid Gel" or "PG" as used herein includes
a one-phase, transparent, translucent or opaque semi-solid mass
(FIG. 1) that comprises 20-80% phospholipids and meets the
"Acceptable Injectability Criterion."
[0069] As used herein, the term "pH buffering agent" includes a
pharmaceutically acceptable pH buffer such as phosphate, acetate,
citrate, bicarbonate, histidine, TRIS, and the like.
[0070] As used herein, the term "phospholipid" includes a lipid
molecule containing one or more phosphate groups, including those
derived from either glycerol (phosphoglycerides,
glycerophospholipids) or sphingosine (sphingolipids). A
phospholipid can be chemically synthesized or extracted from a
natural source. Naturally occurring phospholipids are generally
referred to as "lecithins " According to the United State
Pharmacopoeia (USP), lecithin is a non-proprietary name describing
a complex mixture of acetone-insoluble phospholipids, which are
comprised mainly of phosphotidylcholine, phosphotidylethanolamine,
phosphotidylserine and phosphotidylinositol, combined with various
amounts of other substances such as triglycerides, fatty acids, and
carbohydrates.
[0071] As used herein, the term "primary dispersion" includes an
emulsion or suspension formed in the first step in a process of
making the PG's of the present invention, that contain phospholipid
particles or oil droplets of size greater than 500 nm in diameter.
Such primary dispersions can be readily formed by simple mixing,
such as stirring, or low speed agitation. A dispersion may be
referred to as an "emulsion" if oil is present in the PG
composition.
[0072] As used herein, the term "solubilizing agent" includes
primarily cyclodextrins or surfactants such as polysorbate 80, bile
salt and the like.
[0073] As used herein, a "sugar" includes a safe and biocompatible
carbohydrate agent that protects the nanodispersion during drying
by maintaining the discrete and sub-micron phospholipid particles.
The sugars useful for this invention include, but are not limited
to, monosaccharides, disaccharides, polysaccharides, propylene
glycols, polyethylene glycols, glycerols, poly-ols, dextrins,
cyclodextrins, starches, celluloses and cellulose derivatives, or
mixtures thereof For instance, in certain embodiments, the sugar is
mannitol, sorbitol, xylitol, lactose, fructose, xylose, sucrose,
trehalose, mannose, maltose, dextrose, dextran, or a mixture
thereof In certain embodiments, the preferred sugar is sucrose.
[0074] As used herein, the term "tonicity/osmotic modifying agent"
includes a pharmaceutical additive that can be added to an
injectable pharmacologically active agent and be used to adjust
osmolality to close to 300 mOsm. The tonicity/osmotic modifying
agents useful in this invention include, but are not limited to,
potassium or sodium chloride, trehalose, sucrose, sorbitol,
glycerol, mannitol, polyethylene glycol, propylene glycol, albumin,
amino acid and mixtures thereof.
II. Embodiments
[0075] The present invention provides a one-phase gel composition,
comprising:
[0076] 20 to 80% by weight of one or more phospholipids;
[0077] optionally a pharmacologically active agent; and
[0078] 0.1 to 70% by weight water, wherein the gel composition is
extrudable through a 25 G 1/2 inch long needle from a 1 cc syringe
at an extrusion rate of 2 cc/min by an applied force of no more
than 12 pounds. The phospholipid depots are one-phase gels that can
be aqueous or substantially anhydrous. Preferably, the invention is
directed to certain phospholipid compositions that are suitable for
depot application.
[0079] Suitable synthetic phospholipids useful in the present
invention include, but are not limited to: [0080] (1)
Diacylglycerols, e.g. 1,2-Dilauroyl-sn-glycerol (DLG) and
Dimyristoyl-snglycerol (DMG); [0081] (2) Phosphocholines, e.g.
1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and
1-Palmitoyl-2-01eoyl-sn-glycero-3-phosphocholine (POPC); [0082] (3)
Phosphoethanolamines, e.g.
1,2-Dimyristoyl-sn-glycero-3-phosphoethanolamine (DMPE) and
1,2-Palmitoyl-sn-glycero-3-phosphoethanolamine (POPE); [0083] (4)
Phosphoglycerols, e.g., Egg phosphatidylglycerol, sodium salt (EPG,
Na) and 1,2-Palmitoyl-sn-glycero-3-phospho glycerol, sodium salt
(POPG, Na); [0084] (5) Phosphotidylserines, e.g.
1,2-Dimyristoyl-sn-glycero-3-phospho-L-serine, sodium salt
(DMPS,Na) and 1,2-Dipalmitoyl-sn-glycero-3-phospho-L-serine, sodium
salt (DPPS,Na); [0085] (6) Mixed Chain Phospholipids, e.g.
1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and
1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol, sodium salt
(POPG,Na); [0086] (7) Lysophospholipids, e.g.
1-Myristoyl-2-lyso-sn-glycero-3-phosphocholine (S-lyso-PC) and
1-Palmitoyl-2-lyso-sn-glycero-3-phosphocholine (P-lyso-PC); and
[0087] (8) Pegylated Phospholipids, e.g.
N-(Carbonyl-methoxypolyethyleneglycol 2000)-MPEG-2000-DPPE and
1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine, sodium salt.
[0088] The preferred synthetic phospholipids are POPC and DMPC.
[0089] In accordance with the practice of the present invention,
the selection of a phospholipid for use in the depot compositions
is determined by ability of the phospholipid to (1) form a
nanodispersion and maintain the small particle size through the
manufacturing process and afterwards in storage, (2) be chemically
compatible with the pharmacologically active agent and (3) provide
the desired depot or sustained release properties for the
pharmacologically active agent. Certain combinations of
phospholipids can be utilized to form the depot such as POPC and
DMPC. An optional phospholipid or phospholipid combination for a
depot composition can be selected using the physical and chemical
screening test methods known to those skilled in the art.
[0090] In another embodiment, the PG compositions of the present
invention comprise 2080% by weight, 25 to 70% by weight, and more
preferably 30 to 60% by weight of a phospholipid such as 25%, 30%,
35%, 40%, 45%, 50%, 55%, or 60% by weight of a phospholipid or a
mixture of phospholipids.
[0091] In one embodiment, a PG that contains a significant amount
of water, i.e., about 10% to about 70%, such as 10%, 15%, 20%, 25%,
30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, or 70%, and is referred to
herein as "aqueous gel."
[0092] In another embodiment, a PG is essentially or substantially
free of water, i.e., such as less than 5%, preferably less than 3%
and more preferably less than 1%; such a PG is herein referred to
as an "anhydrous gel." The water content can be a de minimus amount
or about 0.01% to about 5%, or about 0.1% to about 5%, such as
about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%,
1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, or about 5.0% w/w
water.
[0093] In one embodiment, the present invention provides PG
compositions containing pharmacologically active agents, satisfies
the Acceptable Injectability Criterion and are able to deliver a
pharmacologically active agent in a prolonged and peak-less PK
profile.
[0094] In one embodiment, the present invention provides PG
compositions compatible with heat-sensitive pharmacologically
active agents of biological or synthetic chemical origin and
methods of preparation of such PG compositions that permit
sterilization by filtration of the nanodispersion intermediate
through a 0.2- or 0.45-micron pore membrane, thus eliminating the
need for an aseptic process or terminal sterilization using heat or
radiation.
[0095] In another embodiment, the present invention provides
aqueous gel PG compositions that are compatible with biological
molecules such as insulin or other biologically active proteins or
peptides, and methods to prepare such PG compositions, without the
use of damaging amounts of organic solvent. Biological molecules
are easily denatured or destroyed by organic solvents. However, in
accordance with the teachings of the present invention, a
solvent-incompatible biological molecule can be formulated into
aqueous gels as a sustained-release depot.
[0096] In another embodiment, the present invention provides PG
compositions that are essentially devoid of water (i.e., the
anhydrous gels) in order to preserve water-sensitive
pharmacologically active agents while retaining the acceptable
injectability properties in the final product and the desired 0.2-
or 0.45-micron sterile filtration step in the process.
[0097] In a preferred embodiment, the aqueous gels of the present
invention comprises a biological molecule such as a protein, a
peptide, a nucleic acid sequence, a virus, a cell line or a
hydrophilic chemical drug or salt or solvate, and combinations
thereof.
[0098] In another preferred embodiment, the PG gel of the present
invention, either aqueous or anhydrous, comprises a heat-sensitive
pharmacologically active agent such as a protein, a peptide, a
nucleic acid sequence, a virus, a cell line or a sensitive chemical
drug, which would be degraded or destroyed by heat or radiation
typically used for terminal sterilization.
[0099] In yet another embodiment, the present invention provides an
anhydrous gel that contains a water-sensitive pharmacologically
active agent.
[0100] In yet another embodiment, the present invention provides
anhydrous gels that contain lipophilic or water-insoluble
pharmacologically active agents.
[0101] The present invention provides an anhydrous gel that can be
used to dissolve highly water-soluble or hydrophilic
pharmacologically active agents despite the fact that the gel is
essentially water-free. For example, certain pharmacologically
active agents in their salt forms, such as a sodium salt (e.g.,
sodium heparin) or a hydrochloride salt (e.g., lidocaine HCl), are
extremely water-soluble and have very low solubility in oil or
lipid. The invention methods to prepare anhydrous gel disclosed
herein have allowed surprisingly high solubilization of such a
highly hydrophilic pharmacologically active agents in anhydrous
gels that essentially contain no water (EXAMPLES 5 and 6). The
lidocaine HCl anhydrous gel is transparent and free of any
insoluble solid particles. In contrast, using conventional methods
to mix lidocaine with the other components of the anhydrous gel
results in a suspension having most of the pharmacologically active
agent remaining undissolved. This unexpected dissolution property,
together with the absence of water of the anhydrous gel, provides
an advantageous utility for forming depot compositions that contain
pharmacologically active agents that are water-soluble yet
sensitive to water, such as insulin and interferon.
[0102] The present invention provides aqueous gels that can be used
to dissolve extremely water-insoluble or hydrophobic
pharmacologically active agents despite the fact that the gels
contain 20-70% water. For example, hydrophobic pharmacologically
active agents such as docetaxel can be readily dissolved in an
aqueous gel (EXAMPLE 7) and the resulting gel is transparent and
free of any insoluble solid particles. This is in contrast to
conventional methods, which would form a suspension with most of
the hydrophobic pharmacologically active agent remaining
undissolved following its addition into an aqueous composition.
This unexpected dissolution property, together with the absence of
solvent to promote the dissolution, provides an advantageous
utility for forming depot compositions containing water-insoluble
pharmacologically active agents without solvent or solvent-related
safety concerns.
[0103] Table I below summarizes some, but not all, representative
classes of the pharmacologically active agents that can be
formulated as depots by the present invention.
TABLE-US-00001 TABLE I Classes of pharmacologically active agents
Water- soluble Stable in Heat- Exemplary pharmacologically
Applicable (Hydrophilic) water sensitive active agents PG Yes Yes
Yes Insulin (EXAMPLES 2-5, 19, Aqueous Gel 30, and 31) &
Anhydrous Gel Yes No Yes Buprenorphine HC1 (EXAMPLE Anhydrous 6)
Gel No No Yes Docetaxel (EXAMPLE 7) Anhydrous Gel Yes Yes No
Lidocaine (EXAMPLE 8) Anhydrous Gel Yes Yes Yes Exenatide (EXAMPLE
9) Aqueous Gel Yes No Yes Beta Interferon (EXAMPLE 10) Aqueous Gel
Yes Yes Yes Heparin (EXAMPLE 11) Aqueous Gel Yes Yes Yes Epotin
Alpha (EXAMPLE 12) Aqueous Gel Yes No Yes Human Growth Hormone
Anhydrous (EXAMPLE 13) Gel Yes No Yes Adalimumab (EXAMPLE 14)
Anhydrous Gel Yes No Yes Cefazolin & Metronidazole Anhydrous
(EXAMPLE 15) Gel Yes No Yes Bupivacane (EXAMPLE 16) Anhydrous Gel
No Yes No Predisone (EXAMPLE 20) Anhydrous Gel No Yes No Ibuprofen
(EXAMPLE 21) Anhydrous Gel No Yes No Clotriamazole (EXAMPLE 22)
Anhydrous Gel No Yes Yes Risperidone (EXAMPLE 23) Anhydrous Gel No
No No Tamoxifen citrate (EXAMPLE 24) Anhydrous Gel No Yes No
Diazepan (EXAMPLE 25) Anhydrous Gel Yes Yes Yes Insulin determir
(EXAMPLE 30) Aqueous Gel No No Yes NPH Insulin (EXAMPLE 31) Aqueous
Gel Yes Yes Yes BOTOX .RTM. (EXAMPLE 32) Aqueous Gel
[0104] In a preferred embodiment, the phospholipid may be a
lecithin, a synthetic phospholipid, or mixtures thereof. The
preferred concentration of phospholipid is 20 to 80%, preferably 25
to 60%, and more preferably 30 to 50% such as 30%, 35%, 40%, 45%,
or 50% of the PG weight.
[0105] In a preferred embodiment, oil may be used in the present
invention's PG compositions. The oil may be synthetic triglycerides
such as tricaprylin, trimyristin or triolein, vegetable oil, medium
chain oil, vitamin E, vitamin E acetate, vitamin E succinate, oleic
acid or other unsaturated fatty acids or their monoetsers (e.g.,
ethyl oleate) or cholesterol, or mixtures thereof. The preferred
oils are sesame oil, medium chain oil, ethyl oleate and the
synthetic triglycerides and the preferred concentration of oil is 1
to 50%, preferably 2 to 20% and more preferably 5 to 10% of the PG
weight, such as 5%, 6%, 7%, 8%, 9% or 10%.
[0106] In a preferred embodiment, a sugar can be used in the
present PG compositions. The sugar may be sucrose, dextrose,
lactose, glucose, trehalose, maltose, mannitol, sorbitol, glycerol,
amylose, starch, amylopectin or mixtures thereof. The preferred
sugars are sucrose and glycerol.
[0107] The preferred concentration of sugar is 0.5 to 20%,
preferably 1 to 15% and more preferably 2 to 10% such as 2%, 3%,
4%, 5%, 6%, 7%, 8%, 9% or 10% of the PG weight.
[0108] In a preferred embodiment, a solvent can be used in the
invention PG compositions. The solvent may be ethanol, propylene
glycol, glycerol, sorbitol, polyethylene glycol, silicone oil,
glycofurol, ethyl oleate, or mixtures thereof. The preferred
solvents are ethanol, glycerol and propylene glycol. The preferred
concentration of solvent is 0.5 to 20%, preferably 1 to 15% and
more preferably 2 to 10% such as 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or
10% of the PG weight.
[0109] In one embodiment, the invention PG compositions may contain
water. The preferred concentration of water is about 10 to 70% of
the aqueous gel depot weight, and less than about 5%, preferably
less than 3% or most preferably less than 1% of the anhydrous gel
depot weight.
[0110] In one embodiment, the invention PG compositions may
comprise a functional pharmaceutical excipient such as acidifying
agents, alkalizing agents, pH buffering agents, metal ion
chelators, antioxidants, stabilizers, preservatives,
tonicity/osmotic pressure modifiers, condensing agents, or a
mixture thereof The selection of a functional excipient(s) in a PG
composition can be made based on stability requirement or other
pharmaceutical considerations known by those skilled in the art.
Example excipients include, but are not limited to, HCl or NaOH for
the pH adjuster, acetate or histidine for pH buffer, EDTA for the
metal ion chelator, vitamin E, ascorbic acid or cysteine for the
antioxidant, methionine for the stabilizer, meta-cresol, phenol or
benzyl alcohol for the preservative, sodium chloride, glycerol or
sucrose for the tonicity/osmotic pressure modifier, etc.
[0111] In one embodiment, the amount of active agent is about 0 to
20% by weight a pharmacologically active agent. In one embodiment,
the invention PG composition does not contain any pharmacologically
active agent or drug and such "drug-free" PG may be used as a
tissue filler or as a wound salve. In this embodiment, the optional
pharmaceutical active ingredient is absent or not present.
[0112] In other embodiments, the PG contains about
1.0.times.10.sup.-7% to about 1% by weight of a pharmacologically
active agent. In other embodiments, the active agent is about 1 to
about 20% such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, or 20% by weight of a pharmacologically active
agent. In other embodiments, the amount is about 1% to about 6% or
3% to about 8% or even about 4% to about 11% by weight a
pharmacologically active agent.
[0113] In one embodiment, the PG may contain about 0.1 nanogram/g
up to 10 nanogram/g, such as 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7,
0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 ng/mL of an active
ingredient such as Botox.RTM., or about 0.6 to 4.8 nanogram/g or
even about 0.6 to 4.8 nanogram/g of the formulation. In certain
instances, the amount of active ingredient is around
1.0.times.10.sup.-7% by weight. In certain instances, the active
agent is present at about 1.0.times.10.sup.-7% to about 1% by
weight.
[0114] Certain embodiments are preferred. For example, in one
embodiment, the present invention provides a one-phase aqueous gel
composition comprising: [0115] 20 to 80% by weight, preferably 25
to 70% by weight, and more preferably 30 to 60% by weight one or
more phospholipid(s); [0116] 10 to 70% by weight, preferably 20 to
60% by weight, and more preferably 40 to 60% by weight of water;
and [0117] 0 to 20% by weight a pharmacologically active agent,
wherein the gel composition requires an applied force of no more
than 15 pounds to be extruded from a 1 cc syringe through a 25 G
1/2 inch long needle at a rate of 2 cc/min.
[0118] In another embodiment, the present invention provides a
one-phase anhydrous gel comprising: [0119] 20 to 80% by weight,
preferably 25 to 70% by weight, and more preferably 30 to 60% by
weight one or more phospholipid(s); [0120] 5 to 60% by weight,
preferably 10 to 50% by weight, and more preferably 20 to 40% by
weight a non-aqueous component selected from groups comprising
sugar, oil, or solvent, and [0121] 0 to 20% by weight a
pharmacologically active agent, wherein the gel composition
requires an applied force of no more than 15 pounds to be extruded
from a 1 cc syringe through a 25 G 1/2 inch long needle at a rate
of 2 cc/min.
[0122] Further, in accordance with the present invention, there are
provided one-phase gel compositions comprising: [0123] (1) 20 to
80% by weight, preferably 25 to 50% by weight, and more preferably
30 to 40% by weight one or more phospholipid(s), and [0124] (2) 100
to 700 IU/g an insulin, insulin analog, a crystalline insulin with
zinc and/or protamine, an NPH insulin or a combination thereof and
water, wherein the gel composition requires an applied force of no
more than 15 pounds to be extruded from a 1 cc syringe through a 25
G Y2 inch long needle at a rate of 2 cc/min and maintains plasma
glucose concentration below 130 mg/dl for no less than 18 hours
following a subcutaneous injection of 20 IU/kg insulin dose into
streptozotosin-induced type-I diabetic rats.
[0125] In a preferred embodiment, the PG compositions contain at
least one pharmacologically active agent or drug. Suitable
"pharmacologically active agents" contemplated for use herein are
not limited by therapeutic category. Pharmacologically active
agents can be small molecules made by synthetic chemistry or
extraction ("chemical drugs") or biological drugs including
proteins, peptides, oligonucleotides, viruses, cells, and the like.
The PG compositions of the present invention have particular
utility for heat-sensitive pharmacologically active agents,
especially the biological drugs, such as insulin.
[0126] The preferred chemical drugs include, but are not limited
to, antibiotics, anticancer agents, anesthetics, analgesics,
hormones, antidiabetics and metabolic disorder drugs, with examples
including cefazolin, metronidazole, bupivacaine, lidocaine,
buprenorphine, paclitaxel, and docetaxel. The term chemical drugs
also include salts, solvates isomers, active metabolites, or
combinations of the chemical drugs.
[0127] The biological drugs contemplated for this invention
include, but are not -limited to, biologically active agents
selected from (a) blood proteins such as factor IXa, hemoglobin,
protein C; (b) antibiotic peptide such as
bactericidal/permeability-increasing protein (Bpi), magainin,
peptidyl mimetics, protegrin, ramoplanin; (c) enzymes such as
comasain, transforming growth factor, alpha-L-iduronidase,
galactosidase, gelonin, glutamic acid, decarboxylase, ribonuclease,
tpa variants; (d) antibodies such as anti-EFGr, anti-lymphoma
antibody, anti-Her2, anti-Cd11/Cd18 integrin, anti-integrin
receptors, anti-Cd52; (e) hormones such as amylin, extendin-4,
relaxin, bone growth factors, epidermal growth factor, fibroblast
growth factor, hematopoietin, insulin, insulin-like growth
factor-I, leptin, natriuretic peptides, neural growth factors,
parathyroid hormone, thrombopoietin, thymosin alpha-1: (f) enzyme
inhibitors such as angiostatin and endostatin, bivalirudin,
nematode anticoagulant proteins; (g) vaccines; (h) lymphokines such
as interleukin-4, interleukin-6, interleukin-10, interleukin-12,
(h) stem cell factor; (i) myeloid progenitor inhibitory factor-1,
macrophage colony-stimulating factor, botulinin, fusion proteins,
collagen, surfactant protein, protamine sulfate and heparin. The
team biological drugs also include salts, solvates isomers, active
metabolites, or combinations of the biological drugs.
[0128] The preferred biological drugs include, but are not limited
to, insulin, interferon, growth hormone, calcitonin, parathiroid
hormone, exernatide, pramlintide, heparin, granulocyte
colony-stimulating factor (G-CSF), epoetin, adalimumab,
trastuzumab, and mixtures thereof.
[0129] In one embodiment, the present invention provides PG
compositions, which contain insulin and satisfies the Acceptable
Injectability Criterion and are able to maintain a plasma glucose
concentration below 130 mg/dl for no less than 18 hours following a
subcutaneous injection of a 20 IU/kg insulin dose into
streptozotosin-induced type-I diabetic rats.
[0130] In another embodiment, the insulin contained in the PG
compositions of the present invention is of animal origin or is a
recombinant insulin, a human recombinant insulin, a insulin complex
with zinc, protamine or a combination thereof, an insulin analog or
a mixture thereof.
[0131] In yet another embodiment, the PG composition of the present
invention that contains insulin comprises 50 to 1000 IU/g,
preferably 100 to 500 IU/g, more preferably 100 to 400 IU/g such as
100 IU/g, 200 IU/g, 300 IU/g, 350 IU/g or 400 IU/g or most
preferably 100 IU/g insulin, insulin analog or NPH insulin. In
certain aspects, 100 IU is about 3.8 mg of recombinant human
insulin. In still another embodiment, the PG composition of the
present invention that contains insulin comprises about 0.1% to
about 5%, preferably about 0.3% to about 5% such as 0.3, 0.4, 0.5,
0.6, 0.7, 0.8, 0.9, 1.0, 2.0, 3.0, 4.0 or 5.0% insulin.
[0132] In certain embodiments, the one-phase gel composition of the
present invention maintains a peak-less blood insulin vs time
profile in streptozotosin-induced type-I diabetic rats within 24
hours following a subcutaneous injection of 20 IU/kg insulin, and
wherein the insulin concentration ratio of the highest point to the
lowest is no more than 6:1, no more than 5:1, no more than 4:1, or
even no more than 3:1.
[0133] In one embodiment, the present invention provides certain PG
compositions that contain 20 to 80% by weight of one or more
phospholipids and surprisingly satisfies or requires even less
injection force than the Acceptable Injectability Criterion. In
some other embodiments, the present invention provides certain PG
that requires greater injection force than the Acceptable
Injectability Criterion and such PG's may be delivered through a
large needle into certain body cavity such as a surgical wound.
[0134] In another preferred embodiment, this invention relates to
PG compositions, in their injectable, stable and sterilized form,
that provide a unique drug release profile that is prolonged and
peak-less. Such release profile is highly desirable for certain
drugs with short half-lives, such as insulin, and permit them to be
maintained at constant levels in the circulation for a prolonged
time. In a preferred embodiment, the PG compositions and achieve a
24 hr duration PD and peak-less 24 hr duration PK profiles for
human insulin.
[0135] In another preferred embodiment, the PG composition of the
present invention has at least one of the properties listed below,
and is suitable as a replacement for NPH basal insulin therapy:
[0136] 1. Incorporates authentic human insulin (as in NPH); [0137]
2. Administered by the same route as NPH, i.e., subcutaneous
injection; [0138] 3. Delivers a 24 hr peak-less PK profile; [0139]
4. Provides a 24 hr PD profile that is significantly longer than
that shown for NPH; [0140] 5. Has a stability/shelf-life comparable
to the NPH drug; [0141] 6. Is injectable through a fine needle,
i.e., 25 G or smaller; [0142] 7. Has significantly improved
dose-uniformity (i.e., injection-to-injection variability of <3%
relative standard deviation); [0143] 8. Is ready to use and does
not require mixing prior to injection; [0144] 9. Is injectable by
pen injector;
[0145] In another embodiment, the PG compositions and methods of
preparation disclosed herein are useful for both synthetic and
biological drugs. The PG compositions are especially useful for
biological drugs having physical and chemical properties similar to
insulin, i.e., highly water soluble, solvent-incompatible, and
sensitive to heat or radiation.
[0146] The present invention provides PG compositions and their
methods of preparation which have the following unexpected
features: [0147] (1) High phospholipid content (i.e., 20-80%).
[0148] (2) Surprisingly good injectability. [0149] (3) Filterable
through 0.2-0.4 micron filters to enable a
sterilization-by-filtration in the manufacturing process, thus
permitting PGs to be used with heat-and radiation sensitive drugs.
[0150] (4) Compatible with water-soluble or solvent-incompatible
synthetic and biological pharmacologic agents. [0151] (5) Prolonged
and peak-less delivery profile-capable for certain drugs such as
insulin.
III. Methods of Making
[0152] Surprisingly, the aqueous gels and anhydrous gels that are
prepared according to the methods of preparation of the present
invention are easily injectable through fine needles even with
their high phospholipid content (e.g., 20-80%). In some formats,
the aqueous gels or anhydrous gels are transparent in appearance
and silky smooth to the touch. Theologically, these gels are shear
thinning and thixotropic, which are desired properties for good
extrudability/injectability through a fine needle. In contrast, the
same compositions, when prepared by other known prior art methods,
result in thick pastes that are very difficult or impossible to
inject through a fine hypodermic needle (FIG. 4).
[0153] In one embodiment, the present invention provides a method
for preparing a one-phase gel composition, the method comprising:
[0154] a) forming a primary dispersion comprising one or more
phospholipid(s) and an excessive amount of water; [0155] b)
homogenizing the primary dispersion to form a nanodispersion with
an average particle size of about 30 nm to about 200 nm in
diameter; [0156] c) optionally passing the nanodispersion through a
0.2- or 0.45-micron filter; and [0157] d) removing the excessive
water to obtain a one-phase gel composition.
[0158] In certain embodiments, the one-phase gel is an aqueous gel.
In other embodiments, the one-phase gel is substantially an
anhydrous gel. In certain preferred embodiments the one-phase gel
further comprises a pharmacologically active agent. When a
pharmacologically active agent is present, it may be is added
before step "b" or it may be added after step "b". In other
embodiments, it may be added before as well as after step b. In
other embodiments, the present invention provides-a one-phase
aqueous gel (e.g., aqueous or a substantially anhydrous) made by
methods herein.
[0159] In addition, with regard to step "c" of passing the
nanodispersion through a 0.2- or 0.45-micron filter, if included,
the filtration step can be performed either before or after
"removing the excessive water" step in making an aqueous or an
anhydrous gel. Thus, in certain aspects, step "c" is included in
the method, or in certain aspects, step "c" is performed after step
"d". In certain aspects, the filtration step can be eliminated and
the PG is sterilized by heat or radiation or prepared
aseptically.
[0160] In another embodiment, the present invention relates to
unique methods to prepare sterile PG compositions that are
filterable through a 0.2- to 0.45-micron pore membrane to permit
sterilization of the PG preparation by filtration, yet have a 20 to
80% by weight phospholipid content and are able to meet or require
less force than the Acceptable Injectability Criterion.
[0161] In another embodiment, the present invention provides unique
methods to prepare PG compositions to contain water-soluble or
solvent-incompatible drugs such as insulin without any
precipitation or degradation of the insulin, yet having about 20 to
80% by weight phospholipid content and require less injection force
than the Acceptable Injectability Criterion.
[0162] More surprisingly, the aqueous gels prepared according to
the present invention exhibit superior uniformity and physical
stability over a composition containing the same components, but
prepared by methods taught in prior art. FIG. 5 illustrates the
superior uniformity and physical stability of an aqueous gel
produced according to EXAMPLE 1 (right, T-4) over a paste resulting
from mixing the same components but not using the methods of the
present invention to prepare the aqueous gel (left). After
centrifugation (13,000 rpm, 10 minutes), the paste produced by a
prior art method separates into liquid and solid phases whereas the
aqueous gel prepared in accordance with the present invention
remains as a uniform, single-phase gel (Example 27). Such content
uniformity is key for accurate dosing as well as the physical
stability required for adequate product shelf life for
pharmaceutical products.
[0163] In a preferred embodiment, a high-shear, high-energy or
high-pressure homogenizer (such as the microfluidizers from
Microfluidics International Corporation) is used to convert the
primary dispersion to a nanodispersion by reducing the phospholipid
particles in the primary dispersion from more than 500 nm to less
than 200 nm, preferable less than 100 nm and most preferably less
than 50 nm. The reduction of phospholipid particles greatly reduces
viscosity and increases the injectability of the final PG's. For
example, before high-pressure homogenization, a primary dispersion
composition containing about 20% phospholipid is a white, opaque,
thick yogurt-like mass and is not injectable through a 25 G
needle.
[0164] After homogenization in a microfluidizer to reduce the lipid
diameter to about 50 nm, the resulting nanodispersion is a clear,
transparent, thin and water-like liquid with a remarkably reduced
viscosity. After removing the excessive water, the final PG
satisfies the Acceptable Injectability Criterion. The
nanodispersion can also be filtered through a 0.2- or 0.45-micron
filter membrane, allowing sterilization of the PG preparations
prior to parenteral administration. In contrast, the same
phospholipid-containing composition without the homogenization
treatment is not filterable through the same membranes.
[0165] In a preferred aspect, the present invention provides a
method for preparing a one-phase aqueous gel composition,
comprising: [0166] a) mixing the components to form a primary
dispersion comprising one or more phospholipid(s) and excessive
water; [0167] b) homogenizing the primary dispersion to form a
nanodispersion with an average particle size of less than about 200
nm in diameter; [0168] c) passing the nanodispersion through a 0.2-
or 0.45-micron filter; and [0169] d) removing the excessive water
to obtain the aqueous gel.
[0170] In another embodiment, the present invention provides a
method for preparing a one-phase anhydrous gel comprising: [0171]
a) mixing the components to form a primary dispersion comprising
one or more phospholipid(s), and excessive water; [0172] b)
homogenizing the primary dispersion to form a nanodispersion with
an average particle size of less than about 200 nm in diameter;
[0173] c) passing the nanodispersion through a 0.2- or 0.45-micron
filter; and [0174] d) removing water to less than 5%, preferably
less than 3% and more preferably less than 1% by wt of the
anhydrous gel.
[0175] Additionally, in accordance with the present invention,
there are provided one-phase anhydrous gel compositions comprising:
[0176] a) mixing the components to form a dispersion comprising one
or more phospholipid(s), excessive water; [0177] b) removing water
to less than 5%, preferably less than 3% and more preferably less
than 1% by wt of the anhydrous gel; [0178] c) adding a solvent;
[0179] d) mixing to obtain an anhydrous gel, and [0180] e) passing
the gel though a 0.2- or 0.45-micron filter.
[0181] In one particular aspect of making an anhydrous gel, it is
not required to homogenize the primary dispersion. This is
especially advantageous with a PG formulation without an active
ingredient or with a non-heat sensitive or radiation sensitive
active ingredient.
[0182] According to the present invention, a primary dispersion
contains at least about 70-80% water, which is more than needed in
the final PG's. However, this amount of water gives the dispersion
the desired flow properties in order to be processed in the
microfluidizer. Once the nanodispersion is obtained, the excessive
water is removed in order to achieve the final water content in the
PG of 20 to 70% for an aqueous gel or less than about 5%,
preferably about 3%, or more preferably about 1% water content for
an anhydrous gel so that the PG will have the desired properties.
In accordance with the practice of the present invention, it is
important to maintain the small phospholipid particle size during
the water-removing (drying) step to maintain the low viscosity or
high injectability of the final PGs.
[0183] Emulsions or suspensions of phospholipids are
thermodynamically unstable systems. If not processed properly, the
phospholipid droplets or particles will aggregate, merge, grow in
size and eventually result in the phospholipid and separating the
water phases (i.e., creaming out). When this happens the benefit of
the reduced viscosity provided by the nanodispersion is lost.
Surprisingly, in accordance with the practice of the present
invention, the addition of certain sugars provides an unexpected
protective effect for the nanodispersion against the aggregation of
phospholipid particles or droplets during the water removal
processes. The presence of sugar in the nanodispersion thus keeps
the phospholipid nanodispersion particle size essentially unchanged
during the water removal step using the conditions disclosed
herein.
[0184] In certain aspects, as shown in Examples 1 and 2, the
resulting aqueous gels have about the same particle size as in the
nanodispersion, while maintaining excellent injectability
properties for injections through fine hypodermic needles (FIG. 4).
The present inventors have observed that as water is removed from
the nanodispersion to where the PG reaches a water content of 50%
or less, a phase transition occurs that turns the solution-like
nanodispersion into a gel. The PG thus formed is transparent or
translucent, one-phase and remains one-phase even after being
subjected to a strong separation force such as centrifugation. Upon
mixing in water, the PGs of this invention can re-form the
nanodispersion, suggesting that the PGs comprise discrete
nanometer-sized phospholipid particles.
[0185] In contrast, following other known prior art methods that
simply mix the same PG components, even with vigorous agitation for
24 hours, the same compositions as in Example 1 and 2 produced a
pasty mass, which is opaque, not one-phase and did not satisfy the
Acceptable Injectability Criterion (FIG. 4).
[0186] Not wishing to be bound by a theory or mechanism of the
invention, it appears that the superior injectability offered by
the PG's of this invention is attributable to the extremely small
phospholipid particles created by homogenization. This inventor
speculates that by removing the water from the nanodispersion, the
nanometer sized phospholipid particles stack together to form a
certain organized structure like many small deformable "balloons"
filled with oil and stacked together with water in the interstitial
space. As the water is removed, the interstitial space is minimized
causing the balloons to deform to compress into each other to form
a more rigid structure i.e., a gel, but rather than fusing into
each other, the balloons remain discrete in the gel phase. When an
external force is applied (such as from a syringe plunger), the gel
easily deforms and conforms to the needle bore because of the very
small and discrete phospholipid particles, thus allowing for a
superior injectability. FIG. 9 is a schematic representation of the
speculated convention from a nanodispersion (left) to a PG (right)
upon removal of water. The dark dots depict the nanosized
phospholipid particles in the nanodispersion, and the space between
the dots are filled with water as in an aqueous gel or sugar or oil
as in an anhydrous gel. As the water or solvent is removed, the
particles become structurally organized into the gel.
[0187] Depending upon stability of the pharmacologically active
agent and drug delivery/release requirements, a pharmacologically
active agent can be introduced at a different step during the
present invention's process according to the present methods.
[0188] In one embodiment, the present invention provides a method
for dissolving the pharmacologically active agent in the aqueous
phase that can then be mixed with the phospholipid to form the
primary dispersion that is subsequently carried through the rest of
the process. The methods may be used for a water-soluble
pharmacologically active agent and when the pharmacologically
active agent is shear stress-resistant and/or a slower drug release
is desired.
[0189] In another embodiment, the present invention provides
methods to dissolve the pharmacologically active agent in an oil
phase, which contains the phospholipids and, optionally oil, which
can then be mixed with the aqueous phase to form the primary
dispersion that is subsequently carried through the rest of the
process. This method may be used for a lipophilic, water-insoluble
or fat-soluble pharmacologically active agent.
[0190] In yet another embodiment, the present invention provides a
method for introducing the pharmacologically active agent into the
primary dispersion prior to the homogenization step which is
subsequently carried through the rest of the process.
[0191] In another embodiment, the present invention provides a
method for introducing the pharmacologically active agent into the
nanodispersion after the homogenization step which is subsequently
carried through the rest of the process.
[0192] In yet another embodiment, the present invention provides a
method for introducing the pharmacologically active agent into the
gel after the water removal step.
[0193] In one embodiment, the primary dispersion is made by mixing
the oil phase containing phospholipid and other fat-soluble
components with an aqueous phase which contains all water-soluble
components. Alternatively, the primary dispersion is made by mixing
all components with no particular order of addition.
[0194] In another embodiment, the oil phase is made by mixing the
phospholipid and, optionally, oil and the pharmacologically active
agent. Alternatively, the oil phase is made by dissolving the
phospholipid, the pharmacologically active agent and, optionally,
oil in a volatile solvent such as ethanol and then removing the
ethanol.
[0195] In one embodiment, the aqueous phase is made by mixing
water, pH adjuster, pH buffer, chelator, antioxidant, stabilizer,
preservative, and/or tonicity/osmotic pressure modifier to form a
solution. Optionally, a pharmacologically active agent may be
dissolved or added to the aqueous phase.
[0196] In another embodiment, the filtration of the nanodispersion
may be performed using a vacuum filtration method, centrifugation
filtration, or pressurized filtration method. Various models or
makes of 0.2- or 0.45-micron pore filter membranes are available.
Examples include Sartopore, Sartobran P, Millipore, and the like.
In some cases, a pre-filter with a larger pore size may be used.
The primary reason for the filtration step is to sterilize the
preparation.
[0197] In yet another embodiment, removal of water from the
dispersion or nanodispersion can be done by various drying methods,
for example, by rotational vacuum drying method or by sweeping the
nanodispersion with air or nitrogen gas ("air drying"). The
rotational vacuum drying can be performed using
commercially-available rotational evaporators such as a Rotavap
(Buchi). The air drying is accomplished by mechanically stirring
the nanodispersion while sweeping its surface with a stream of air
or nitrogen gas. The air or nitrogen gas may be filtered through a
0.2- or 0.45-micron pore filter to sterilize. Nitrogen gas is
preferred if any components in the composition are prone to
oxidation.
[0198] In one embodiment, a solvent is added to faun the anhydrous
gel, to 0.5 to 20%, preferably 1 to 15% and more preferably 2 to
10% of the anhydrous gel weight to improve the
injectability/filterability. An example of the suitable solvents is
ethanol, which could be added from 1 to 10% by weight. Prior to
adding to the gel, the solvent may be first sterilized (e.g., by
filtration through a 0.2- or 0.45-micron rated filter). After
addition, the mixture is agitated to form a uniform anhydrous
gel.
[0199] In another embodiment, the anhydrous gel containing the
solvent is sterilized by filtration through a 0.2- or 0.45-micron
pore filter at the end of the process.
[0200] In some embodiments, the aqueous or anhydrous gels are
filled into syringes to certain volume under aseptic conditions and
are ready for injecting after attaching needles to the syringes.
The pre-filled syringe format is convenient for
self-administration. The preferred syringe size is 1-10 mL and the
preferred needle size is 25-29 G.
[0201] In one embodiment, the aqueous or anhydrous gels, after
being injected into a soft tissue (e.g., subcutaneous or
intramuscular injection), provide a slow drug release in vivo as
shown by a prolonged plasma drug concentration-time profile,
compared to the same pharmacologically active agent without a depot
composition. The preferred profile covers 1, 3, 5, 7, 10 and 14
days (FIG. 2, FIG. 7 & FIGS. 8A-8B).
[0202] In another embodiment, the aqueous or anhydrous gels, after
being injected into a soft tissue (e.g., subcutaneous or
intramuscular injection), provide a prolonged drug residence time
at the injection site as shown by a maintained drug concentration
or a sustained local drug activity at the injection site-time
profile compared to the same drug without a depot composition. The
preferred profile covers 1, 3, 5, 7, 10 and 14 days (FIG. 3, FIG. 7
& FIGS. 8A-8B).
[0203] In certain aspects, the formulation has a dynamic viscosity
of about 100, 200, 500, 1000, 3000, and 5000 centipoise (cP). In
certain aspects, the dynamic viscosity of the formulation is at
about 5000, 10,000, 50,000, 75,000, 1.times.10.sup.5,
1.times.10.sup.6, 1.times.10.sup.7, 1.times.10.sup.8 or
1.times.10.sup.9 cP at STP. In yet other aspects, the formulation
is thixotropic.
[0204] In certain aspects, the PG formulation of the present
invention is acidic to neutral. In certain aspects, the formulation
has a pH of about 3 about 8.5. In certain other aspects, the
formulation has a pH from about 5 to about 8.5, from about 5.5 to
about 8.1, about 6 to about 7.9, about 5.5 to about 7.9, or from
about 6.5 to about 7.5.
[0205] In a preferred aspect, the PG formulations of the present
invention comprise a pH-adjusting agent. In one embodiment, the
pH-adjusting agent is a base. Suitable pH-adjusting bases include
amines (e.g., diethanolamine or triethanolamine), bicarbonates,
carbonates, and hydroxides such as alkali or alkaline earth metal
hydroxides as well as transition metal hydroxides. The pH-adjusting
agent is preferably sodium hydroxide and is present in an amount
sufficient to adjust the pH of the composition to between about pH
4.0 to about 8.5; more preferably, to between about pH 5.5 to about
7.0, such as 6.0 or 6.5. Alternatively, the pH-adjusting agent can
also be an acid, an acid salt, or mixtures thereof In a preferred
embodiment, the pH-adjusting agent is an acid.
[0206] Further, the pH-adjusting agent can also be a buffer.
Suitable buffers include citrate/citric acid buffers,
acetate/acetic acid buffers, phosphate/phosphoric acid buffers,
formate/formic acid buffers, propionate/propionic acid buffers,
lactate/lactic acid buffers, carbonate/carbonic acid buffers,
ammonium/ammonia buffers, and the like. In certain embodiments, the
buffer is an acidic buffer system (e.g., benzocaine).
[0207] The invention will now be described in greater detail by
reference to the following non-limiting examples.
Example 1
Preparation of Aqueous Gels (Having No Pharmaceutically Active
Agent) Using Lecithin
TABLE-US-00002 [0208] Components F-1 T-3 T-4 T-5 Compositions (Wt %
in primary dispersion) (Wt % in PG) Sesame oil 4.0 6.6 8.0 10.1 Soy
lecithin 15.0 24.7 30.2 38.0 Cholesterol 0.6 1.0 1.2 1.5 Vitamin E
0.3 0.5 0.6 0.8 succinate (VES) Sucrose 5.0 8.2 10.1 12.7
De-ionized water 75.1 59.0 50.0 37.0 (DI-water) Total 100 100.0
100.0 100.0 Name Supplier Grade Sesame oil Croda Super-refined, USP
Soy lecithin LIPOID EP (Phospholipon 90G) Cholesterol Solvay
Pharmaceuticals HP, NF VES Spectrum Chem. USP Sucrose Spectrum
Chem. NF De-ionized water Latitude Pharmaceuticals Inc.
Procedure
[0209] The F-1 primary dispersion first was prepared and converted
to three aqueous gels (T-3, T-4 and T-5) by the following
procedure: [0210] 1. Weigh out sesame oil, Phospholipon 90 G and
cholesterol into a glass flask. [0211] 2. Add 50 mL ethanol USP.
[0212] 3. Rotate the flask to dissolve all solids. [0213] 4. Vacuum
dry to remove ethanol to less than 1% by weight. [0214] 5. Add VES
(in a 5% stock solution), sucrose and DI-water to 500 g total
weight. [0215] 6. Rotate the flask to mix to form a primary
dispersion. [0216] 7. Homogenize the primary dispersion using a
Microfluidics International Corp Model M-110EH to obtain a
nanodispersion. Continue the process until the average particle
diameter is about 69 nm as determined by laser light scattering
(Malvern Nano Zetasizer). Record pH which is 5.9 [0217] 8. Filter
the nanodispersion through a 0.45-micron disposable vacuum filter
(Nalgene) in a biosafety hood to sterilize. [0218] 9. Aseptically,
remove water by a rotational evaporator (Buchi Model R-205 Rotavap)
until the water content is about 59%, 50% and 37% by weight to
obtain respectively, T3, F-4 and T-5.
[0219] The T-3, T-4 and T5 were one-phase, uniform, and
translucent/transparent gels (FIGS. 1A-1C) that were readily
injectable and met the Acceptable Injectability Criterion defined
herein. Their water contents were confirmed by a moisture balance.
The average particle sizes after being re-dispersed in water were
determined as 63, 62 and 56 nm, respectively, for T-3, T-4 and T-5,
as determined by laser light scattering. All three gels were
filterable through 0.2-micron filters.
[0220] The compositions of this example can be used as tissue
fillers for various indications such as cosmetic wrinkle
removal.
Example 2
Preparation of Aqueous Gels Containing Recombinant Human Insulin
for Basal Insulin Therapy
[0221] Aqueous gels containing recombinant human insulin and 40%,
50% and 60% water were prepared using lecithin. Insulin was
introduced into the process before microfluidization and the
resulting nanodispersion was filtered for sterilization. Thus, no
heat or radiation sterilization was needed in the process.
TABLE-US-00003 Compositions (% wt) Nanodispersio Aqueous Gel
Component F-1 F-2 F-3 F-4 Recombinant 74.9 (IU/g) 84.9 (IU/g) 100
(IU/g) 115.4 (IU/g) human insulin Sesame oil 4.0 6.43 8.03 9.64 Soy
lecithin 15.0 24.10 30.12 36.14 Cholesterol 0.6 0.96 1.20 1.45
Vitamin E 0.3 0.48 0.60 0.72 succinate (VES) Sucrose 5.0 8.03 10.04
12.05 EDTA 0.015 0.018 0.020 0.023 disodium dehydrate De-ionized
75.1 60 50 40 water (DI-water)
[0222] Procedure
[0223] The F-1 nanodispersion was first prepared and converted to
three anhydrous gels (F-2, F-3 and F-4) containing 40, 50 and 60%
water as follows: [0224] 1. Weigh out sesame oil, soy lecithin and
cholesterol into a glass flask. [0225] 2. Add ethanol USP. [0226]
3. Rotate the flask to dissolve all solids. [0227] 4. Vacuum dry to
remove ethanol to less than 1% by weight. [0228] 5. Add VES (in a
5% stock solution), sucrose, EDTA and DI-water. [0229] 6. Add a
recombinant human insulin stock solution (Humulin R U100 by Eli
Lilly and Co.). [0230] 7. Mix to form a primary dispersion. [0231]
8. Adjust pH to 6.8 using NaOH/HCl. [0232] 9. Homogenize the
primary dispersion using a Microfluidics International Corp. Model
M-110EH to obtain a nanodispersion. Continue the process until the
average particle diameter is about 88 nm as determined by laser
light scattering (Malvern Nano Zetasizer). [0233] 10. Filter the
nanodispersion through a 0.2-micron filter (Millipore Sterflip) in
a biosafety hood to sterilize the nanodispersion. [0234] 11.
Aseptically, remove water using a rotational evaporator to reach
water content at 60% to obtain the F-2 gel. Continue the drying
process to 50% water for F-3, and 40% for F-4.
[0235] The F-2, F-3 and F-4 aqueous gels were one-phase and
translucent gels. All satisfied the Acceptable Injectability
Criterion. The insulin concentration and integrity were confirmed
by an RP-HPLC analysis according to USP.
Example 3
Preparation of Aqueous Gels Containing Recombinant Human Insulin
for Basal Insulin Therapy
[0236] The procedure was directed to preparation of aqueous gels
containing recombinant human insulin at 100 IU/mL and 50% water
using a soy lecithin (F-1G) and a synthetic phospholipid (F-5G).
The insulin was introduced into the process before
microfluidization.
TABLE-US-00004 Component F-1G F-5G Compositions (% wt)
(Nanodispersion) (Gel) (Nanodispersion) (Gel) Recombinant human
insulin 0.284 0.379* 0.284 0.379* Sesame oil 4 8.03 4 8.03
Phospholipon 90G (PL90G) 15 30.12
1-Palmitoy1-2-01eoyl-sn-glycero-3- 15 30.12 phosphocholine (POPC)
Cholesterol 0.6 1.2 0.6 1.2 Vitamin E succinate (VES) 0.3 0.6 0.3
0.6 Sucrose 5 10.04 5 10.04 EDTA disodium dehydrate 0.011 0.015
0.011 0.015 Histidine 0.078 0.104 0.078 0.104 De-ionized water
(DI-water) 75.1 50 75.1 50 *Equivalent to 100 IU/g
[0237] Procedure
[0238] The nanodispersions were first prepared and converted to the
anhydrous gels following the steps below: [0239] 1. Weigh out
sesame oil, PL9OG or POPC and cholesterol into a glass flask.
[0240] 2. Add ethanol USP. [0241] 3. Rotate the flask to dissolve
all solids. [0242] 4. Vacuum dry to remove ethanol to less than 1%
by weight. [0243] 5. Add VES (in a 5% stock solution), sucrose,
EDTA, histidine and DI-water. [0244] 6. Add recombinant human
insulin powder (Incelligent SG by Millipore, 26.4 USP unit/mg)
[0245] 7. Mix to form a primary dispersion. [0246] 8. Adjust pH to
7 using NaOH/HCl. [0247] 9. Homogenize the primary dispersion using
a Microfluidizer Model M-110EH to obtain a nanoemulsion. Continue
the process until the average particle diameter is about 53 nm as
determined by laser light scattering (Malvern Nano Zetasizer).
[0248] 10. Filter the nanodispersion through a 0.2-micron filter in
a biosafety hood for sterilization. [0249] 11. Aseptically, remove
water by a rotational evaporator until the water content is about
50% to obtain an F-1G or F-5G aqueous gel.
[0250] The F-1G and F-5G were one-phase, colorless (F-5G) and
transparent gels. Both met the Acceptable Injectability Criterion
(FIGS. 1A-1C). Water contents were confirmed by thermogravimetric
analysis.
Example 4
Preparation of Recombinant Human Insulin Aqueous Gels Containing
Additional Functional Excipients for Basal Insulin Therapy
[0251] The following compositions were made using the same
procedure as described in EXAMPLES 1 to 3 to prepare aqueous gels,
but contained recombinant human insulin at 100 IU/mL and water at
50% water. However, a synthetic phospholipid and various other
excipients were added in the aqueous phase to increase stability.
Sucrose, EDTA disodium dehydrate, M-cresol, phenol, L-histidine,
L-cysteine, zinc (as zinc chloride), and/or protamine sulfate were
dissolved in the aqueous phase first. The insulin was introduced
into the process before the microfluidization step.
TABLE-US-00005 Compositions % Wt F-6G F-7G F-8G F-9G Recombinant
Human Insulin 0.379 0.379 0.379 0.379 powder (at 26.4 U/mg) Sesame
oil 8 8 8 8 POPC 30 30 30 30 Cholesterol 1.2 1.2 1.2 1.2 VES 0.6
0.6 0.6 0.6 Sucrose 10 10 10 10 EDTA disodium dehydrate 0.1
M-CRESOL 0.16 0.16 0.16 0.16 Phenol 0.065 0.065 0.065 0.065
L-Histidine 0.1 0.1 0.1 0.1 L-cysteine 0.1 0.1 Zinc 0.0025
Protamine sulfate 0.024 Water DI- 49.40 49.50 49.40 49.37 Total 100
100 100 100
[0252] F-6 G, F-7 G, F-8 G and F-9 G were one-phase, colorless and
transparent/translucent (or opaque in the case of F-9G) gels. All
were readily injectable through a 26 G needle. The insulin
concentration and integrity in each gel were confirmed by an
RP-HPLC analysis according to the standard USP method.
Example 5
Preparation of Anhydrous Gels Containing Humulin R and Humulin NPH
for Basal Insulin Therapy
[0253] The procedure was directed to preparation of anhydrous gels
containing recombinant human insulin (Humulin R) and recombinant
human insulin zinc/protamine complex (Humulin N, or NPH) at about
100 IU/g. Humulin R or Humulin NPH are insoluble in oil,
incompatible with organic solvents and are heat-sensitive. This
method allows dissolution or incorporation of these hydrophilic
pharmacologically active agents into a sterilized water-free
anhydrous gel without using a terminal heat sterilization step in
the process.
TABLE-US-00006 Composition (% wt) Component S-4 S-9 Humulin R 100
IU/mL / Humulin NPH / 100 IU/mL Soy lecithin 54 54 Sesame oil 40 40
Ethanol 6 6
Procedure
[0254] A 1 g batch for S-4 or S-9 was prepared as follows: [0255]
1. Weigh out sesame oil, soy lecithin and water-for-injection into
a plastic tube. [0256] 2. Homogenize using a Beadbeater to form a
nanodispersion. [0257] 3. Pass through a 0.2 micron pore filter.
[0258] 4. Add Humulin R solution or Humulin NPH suspension to the
filtered emulsion. Mix well. [0259] 5. Lyophilize the
nanodispersion to remove water to less than 1%. [0260] 6. Add
ethanol. [0261] 7. Mix well to obtain an Anhydrous Gel (S-4 and
S-9).
[0262] The S-4 was a one-phase and translucent gel and S-9 was a
one-phase opaque gel. Both gels were readily injectable through a
26 G needle. The insulin strengths in these gels were confirmed by
HPLC analysis.
Example 6
Preparation a Long-acting Depot Comprising an Anhydrous Gel
Containing Buprenorphine Hydrochloride
[0263] The procedure was directed to preparation of an anhydrous
gel containing water-soluble anesthetic buprenorphine
hydrochloride. Buprenorphine hydrochloride is insoluble in oil and
is heat-sensitive. This method allows a complete
dissolution/incorporation of this hydrophilic pharmacologically
active agent in a water-free anhydrous gel without the need for a
terminal heat sterilization step in the process.
TABLE-US-00007 Composition (% wt) Component F-27 Buprenorphine HC1
0.52 1,2-Dimyristoyl-sn-glycero-3-phosphoglycerol, 0.71
ammonium/sodium salt (DMPG) Phospholip on 90G 55.49 Castor oil
36.99 Benzyl alcohol 1.00 Ethanol 5.00 EDTA disodium dehydrate 0.05
Sodium phosphate monobasic 0.24
Procedure
[0264] A 10 g (final gel weight) batch of F-27 was prepared as
follows: [0265] 1. Weigh out castor oil, lecithin, benzyl alcohol,
bupronorphine HCl and DMPG into a plastic bottle. Mix to form an
oil phase. [0266] 2. Weigh out EDTA, sodium phosphate monobasic and
Water-for-Injection, USP (WFI) in a separate container; shake to
dissolve all solids and adjust pH to 7 to obtain an aqueous phase.
Filter the aqueous phase. [0267] 3. Add the aqueous phase to the
oil phase. Shake vigorously to form a primary dispersion. [0268] 4.
Homogenize by sonication to form a nanodispersion. [0269] 5.
Freeze-dry the nanodispersion to remove water to less than 2%.
[0270] 6. Add ethanol. [0271] 7. Mix well to obtain an Anhydrous
Gel (F-27).
[0272] F-27 was a one-phase, opaque gel that was readily injectable
through a 26 G needle. The buprenorphine strength in this gel was
confirmed by HPLC and the water content confirmed using
thermogravimetric analysis. The resultant gel is intended as a
long-acting depot (e.g., once-a-week dosing) for systemic analgesia
or for treatment of narcotic drug abuse.
Example 7
Preparation of an Aqueous Gel Containing Docetaxel
[0273] The procedure was directed to preparation of an aqueous gel
(F-177) containing a highly water-insoluble drug docetaxel and 50%
water using a soy lecithin. Docetaxel was introduced into the
process before microfluidization. This docetaxel gel depot is for
intratumor injection to provide a prolonged anticancer
activity.
TABLE-US-00008 Compositions (% wt) F-177 Primary Component
dispersion Gel Docetaxel trihydrate 0.600 0.811 Miglyol 812 4.000
5.405 Soybean oil 4.000 5.405 Soy lecithin 10.000 13.514
Cholesterol 0.6 0.811 Vitamin E succinate (VES) 0.3 0.404 Sucrose
17.5 23.649 Water-for-Injection 67 50 1N NaOH/HC1 adjust pH to
7.6
Procedure
[0274] A 500 g (primary dispersion wt) batch was prepared and
converted to an aqueous gel as follows: [0275] 2. Weigh out
docetaxol trihydrate, Miglyol 812, soybean oil, soy lecithin and
cholesterol into a glass flask. [0276] 3. Add 500 mL ethanol USP
200 proof. [0277] 4. Rotate the flask to dissolve all solids at
50.degree. C. [0278] 5. Vacuum dry to remove ethanol to less than
2% by weight. [0279] 6. Add VES (in a 5% stock solution), sucrose
and DI-water. [0280] 7. Mix to form a primary dispersion. [0281] 8.
Adjust pH to 7.6+/-0.2 using NaOH/HCl. [0282] 9. Homogenize the
primary dispersion using a Microfluidics International Corp. Model
M-110EH to obtain a nanodispersion. Continue the process until the
average particle diameter is about 100 nm as determined by laser
light scattering (Malvern Nano Zetasizer). [0283] 10. Filter the
nanodispersion through a 0.2-micron pore filter in a biosafety hood
to sterilize the nanodispersion. [0284] 11. Aseptically, remove
water from the nanodispersion using a rotational evaporator until
the water content is about 50% to obtain the F-177 aqueous gel.
Example 8
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Lidocaine
[0285] This procedure was directed to preparation of an anhydrous
gel containing the highly water-soluble local anesthetic lidocaine.
This method also allows incorporation of the water-soluble (and
fat-insoluble) excipients (i.e., EDTA disodium dihydrate and
potassium monobasic phosphate, KOH) in the anhydrous gel.
TABLE-US-00009 Composition (% wt) Component F-20 Lidocaine 2 Soy
lecithin 45 Sesame oil 44 EDTA disodium dehydrate 0.10 Potassium
monobasic phosphate 0.14 Benzyl alcohol 1 Ethanol 4 1N KOH pH to
7.0
Procedure
[0286] A 20 g (final gel weight) batch was prepared as follows:
[0287] 1. Weigh out lidocaine, sesame oil, soy lecithin and benzyl
alcohol into a glass flask. [0288] 2. Add ethanol USP 200 proof and
rotate the flask to dissolve all. [0289] 3. Vacuum dry to remove
ethanol to less than 1% by weight. [0290] 4. Add KH.sub.2PO.sub.4,
EDTA and DI-water. [0291] 5. Homogenize to form a nanodispersion.
[0292] 6. Adjust pH to 7.0+/-0.2 using NaOH/HCl. [0293] 7. Sterile
filter the nanodispersion through a 0.2 micrometer pore filter.
[0294] 8. Lyophilize the nanodispersion to remove water to less
than 2%. [0295] 9. Add ethanol. [0296] 10. Mix well to obtain an
anhydrous Gel (F-20).
[0297] The F-20 is a one-phase, slightly yellow and translucent gel
that is readily injectable through a 26 G needle.
Example 9
Preparation of an Aqueous Gel Containing Exenatide as a Long-Acting
Depot
[0298] An aqueous gel depot is prepared to contain about 2 mg/mL
exenatide using a composition and method as described in EXAMPLE 3.
The resultant gel is a long-acting depot (e.g. once-a-week dosing)
of this anti-diabetic drug.
Example 10
Preparation of a Long-acting Depot Comprising an Aqueous Gel
Containing Interferon Beta-1 a.
[0299] An aqueous gel depot is prepared to contain about 35-350
microgram/mL interferon beta-1a using a composition and method as
described in EXAMPLE 3 and 4. The resultant gel is a long-acting
depot (e.g., once-a-week dosing) and reduced injection site
reaction of this anti-viral, antiproliferative and immunomodulatory
drug.
Example 11
Preparation of a Long-acting Depot Comprising an Aqueous Gel
Containing Heparin
[0300] An aqueous gel is prepared to contain about 40-500
microgram/mL enoxaparin sodium (Lovenox) using a composition and
method as described in EXAMPLES 3 and 4. The resultant gel is a
long-acting depot (e.g. once-a-week dosing) for prophylaxis and
treatment of deep vein thrombosis (DVT), ischemic angina and
myocardial infarction.
Example 12
Preparation of Long-Acting Depot Comprising an Aqueous Gel
Containing Epoetin alpha
[0301] An aqueous gel depot is prepared to contain about 10-30K
units/mL Epoetin alpha (EPOGEN.RTM.) using a composition and method
as described in EXAMPLES 3 and 4. The resultant gel is a
long-acting depot (e.g., once-a-week dosing) for
erythrocytopenia.
Example 13
Preparation of Long-Acting Depot Comprising an Anhydrous Gel
Containing Growth Hormone
[0302] An anhydrous gel is prepared to contain about 5-50 mg/mL
human growth hormone (somatropin) using a composition and method as
described in EXAMPLES 5 and 6. The resultant gel is a long-acting
depot (e.g. once-a-week dosing) for growth hormone deficiency in
pediatric and adult patients, Turner syndrome and SHOX
deficiency.
Example 14
Preparation of Long-Acting Depot Comprising an Anhydrous Gel
Containing Adalimumab
[0303] An anhydrous gel depot is prepared to contain 1 to 20%
adalimumab (Humira) using a composition and method as described in
EXAMPLES 5 and 6. The resultant gel is a long-acting depot (e.g.
once-a-week dosing) for treatment of arthritis, psoriasis,
ankylosing spondylitis and Crohn's disease.
Example 15
Preparation of a Long-Acting Depot Comprising an Anhydrous Gel
Containing Cefazolin, Metronidazole or a Combination Thereof
[0304] An anhydrous gel depot is prepared to contain about 5 to 20%
Cefazolin, 50 mg/mL Metronidazole or a combination thereof using a
composition and method as described in EXAMPLES 5 and 6. The
resultant gel is a long-acting depot following instillation into
surgical wound or injection into the soft tissue near the surgical
wound to prevent post surgical infection.
Example 16
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Bupivacaine
[0305] An anhydrous gel depot is prepared to contain about 40 mg/mL
bupivacaine HCl using a composition and method as described in
EXAMPLES 5 and 6. The resultant gel is a long-acting depot
following instillation into a surgical wound or injection into the
soft tissue surrounding the surgical wound to alleviate post
surgical pain.
Example 17
Prolonged and Peak-less Pharmacokinetic Profile by an Anhydrous Gel
Containing Buprenorphine HCl in Dogs
[0306] A pharmacokinetic study was conducted where 6 dogs were
administered at 0.25 mg/kg dose by subcutaneous or intramuscular
injection of the F-27 anhydrous gel depot as described in EXAMPLE
6. Plasma samples were taken and the buprenorphine content analyzed
by LC-MS. The results are shown in FIG. 2. The plasma profiles
reveal that F-27 depot provided a prolonged in vivo release for at
least 5 days with a low initial burst. The prolonged, controlled
and essentially peak-less PK profile can be a very desirable
feature for drugs where a high C.sub.max may cause adverse
effects.
Example 18
Prolonged Local Analgesic/Anesthetic Efficacy of Lidocaine from an
Anhydrous Gel Prepared According to the Method in EXAMPLE 8
Following Intracutaneous Injection in Guinea Pigs
[0307] This study was intended to compare the prolonged local
analgesic/anesthetic activity of lidocaine in the F-20 depot
formulation to an immediate release solution formulation in guinea
pig pinprick pain model. An anhydrous gel (F-20 composition)
containing the highly water soluble (and oil insoluble) lidocaine
was prepared as described in EXAMPLE 8 and a solution formulation
("Control") was also prepared based on the Lidocaine Solution for
Injection, USP. Male guinea pigs between 300.about.350 grams in
body weight were used. The anesthesia/analgesia activity was
determined using the intracutaneous wheal pinprick model as
described in U.S. Pat. No. 6,045,824 by Kim. On the day preceding
the injection, the backs of the animals were clipped. Each animal
received a 0.25 mL intracutaneous injection of the lidocaine
formulation. The reaction to pinpricks at the site of injection was
tested just prior to injection (pre-injection) and at specific time
points after the injection. The pinpricks were to be applied first
to an area outside the wheal at each time point for positive
control. After observing the animals' normal reaction to the
pinprick (vocalization response), six pricks were applied inside
the wheal and the pricks in which a guinea pig failed to react out
of the six were recorded as no-pain responses. The pinpricks were
applied in the order of left, center, right, upper, center and
lower sections inside the wheal at an interval of 3-5 sec between
the pricks. Prior to the injections, all animals were checked for
their vocalization reaction to pinpricks as baseline responses.
FIG. 3 illustrates the local anesthetic efficacy in percent no-pain
response over time for both formulations. The Control animals
exhibited 100% analgesic/anesthetic effect at 15 minutes after the
injection. However, such effect disappeared quickly with about 50%
activity remained after 1 hour and virtually no activity after 4
hours. This is consistent with the short-term anesthetic nature of
lidocaine. F-20 provided prolonged local drug activity with about
50% and 40% analgesic activity observed at 12 and 24 hours,
respectively, after the injection.
Example 19
Injectability Test for an Aqueous Gel Containing Insulin (F-43)
[0308] An aqueous gel coded as F-43 in the following composition
was prepared using the method as described in EXAMPLE 2, where the
insulin was added after the microfluization step and the average
diameter of particles in the nanodispersion was about 40 nm.
TABLE-US-00010 Component % wt Recombinant Human Insulin 100 IU/g
(or about 0.38% wt) POPC 30 Sesame oil 8 Cholesterol 1.2 Vitamin E
succinate 0.6 Sucrose 2 Glycerin 1.6 Meta-cresol 0.027 Phenol 0.16
Dibasic sodium phosphate anhydrous 0.065 L-methionine 0.15 Zinc
oxide 0.378 Protamine base 0.027 Water for Injection, USP, q.s.
About 56
[0309] F-43 was a translucent one-phase gel. The injectability of
F-43 was determined against the Acceptable Injectability Criterion.
The maximum force required during the injectability test is
recorded as the most relevant measurement parameter for
injectability. F-43 was filled into a lcc B-D syringe (B-D Luer-Lok
Tip, ref 309628) to which a 1/2'' long 25 G needle (EXEL,
Hypodermic needle, ref 26403) was attached. The filled syringe was
loaded onto a syringe pump to which a force meter (Advanced
Precision Instrument Model HP-500) was attached against the plunger
end to measure to force applied to extrude the syringe contents.
The syringe pump was set at 2 cc/min speed and 0.4 mL extrusion
volume. The force was recorded in pounds. In the "push" mode, the
force is recorded as negative. A representative injection force
versus time profile for F-43 is shown in FIG. 6 (upper panel). For
comparison, the force profile from the same composition as F-43,
but prepared by one-step vigorous homogenization of all the
components together ("Same composition by other method"). With a
maximal injection force of less than 1.5 pounds, F-43 is regarded
as highly injectable and meeting the Acceptable Injectability
Criterion. It is compared very favorably to "Same composition by
other method", which required a maximum force of about 14 pounds in
the evaluation. F-43 was also filled into an insulin pen cartridge
(Eli Lily Humulin N Cartridge) and injected using a pen injector
device (HumaPen Luxura by Eli Lilly and company). At a dialed
injection volume of 20 U, the injected volume in repeated
injections was found to be accurate and precise. F-43 is well
suited for pen injectors.
Example 20
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Prednisone
[0310] An anhydrous gel depot is prepared to contain about 40 mg/mL
prednisone using a composition comprising 50% soy lecithin, 40%
sesame oil, and 6% ethanol using the method as follows: [0311] a.
Mix soy lecithin, water and sesame oil to form a primary
dispersion. [0312] b. Remove water by lyophilization to less than
1%. [0313] c. Add ethanol. [0314] d. Mixing to obtain an anhydrous
gel. [0315] e. Pass the gel though a 0.45-micron filter for
sterilization. The resultant gel is a long-acting depot for
treatment of inflammation.
Example 21
Preparation of an Anhydrous Gel Containing Ibuprofen
[0316] An anhydrous gel depot is prepared to contain about 4 to 20%
wt ibuprofen using a composition and method as described in EXAMPLE
20. The resultant gel is a long-acting depot for treatment of
inflammation and pain.
Example 22
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Clotrimazole
[0317] An anhydrous gel depot is prepared to contain about 40 mg/mL
clotrimazole using a composition and method as described in EXAMPLE
20. The resultant gel is a long-acting depot for treatment of
fungal infection.
Example 23
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Risperidone
[0318] An anhydrous gel depot is prepared to contain about 40 mg/mL
Risperidone using a composition and method as described in EXAMPLE
6. The resultant gel is a long-acting depot for treatment of
psychological disorder.
Example 24
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Tamoxifen Citrate
[0319] An anhydrous gel depot is prepared to contain about 51 mg/mL
Tamoxifen Citrate using a composition and method as described in
EXAMPLE 6. The resultant gel is a long-acting depot for treatment
of cancer.
Example 25
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Diazepam
[0320] An anhydrous gel depot is prepared to contain about 40 mg/mL
Diazepam using a composition and method as described in EXAMPLE 20.
The resultant gel is a long-acting depot for treatment of
anxiety.
Example 26
Preparation of a Long-acting Depot Comprising an Anhydrous Gel
Containing Docetaxel
[0321] An anhydrous gel depot is prepared to contain about 40 mg/mL
Docetaxel using a composition and method as described in EXAMPLE
20. The resultant gel is a long-acting depot for treatment of
cancer.
Example 27
Prolonged (24 hr) Insulin Pharmacodynamic Effect by Aqueous Gels
Containing Insulin (F-43 and F-44)
[0322] The objective of this study was to evaluate two aqueous gel
PG compositions containing recombinant human insulin F-43 (as in
EXAMPLE 19) and F-44 in the streptozotosin (STZ)-induced type-I
diabetic Sprague Dawley rat model. This study compared the
pharmacodynamic or PD (i.e., blood glucose level versus time)
profiles for two PG depots with the PD profiles for two marketed
basal insulin drugs (Insulin NPH or Humulin N and Lantus) all at
about 100 IU/mL strength. F-44 was prepared as an Aqueous gel
comprising 100 IU/mL recombinant human insulin, 50% POPC, zinc,
protamine, phenol, m-cresol, glycerol, sodium phosphate and about
40% water using the method as described in EXAMPLE 2, wherein the
insulin was added after the microfluization step.
[0323] Type I diabetes in Sprague Dawley rats was induced by
intravenous injection of STZ. Twenty-four (24) STZ-treated rats
were randomly divided into 4 groups. Small blood samples were taken
from the lateral tail vein of each animal and the blood glucose
levels were measured using a glucometer. The animals were
successfully assigned to treatment groups such that there were no
significant differences between groups in body weight or blood
glucose level as measured by one-way ANOVA (P>0.05). The animals
were fasted for at least 12 hours and then the blood glucose levels
were measured just prior to administration of the test articles.
The four formulations were administered subcutaneously at 20 IU/kg.
Blood glucose levels were measured at -0.25, 0.25, 5, 1, 2, 4, 6, 8
16 and 24 hr post-insulin administration in Experiment 1. Blood
glucose levels were focused on the late time points for experiment
2 at -0.25, 1, 2, 12, 14, 16, 18, 20, 22, 24 and 36 hr post-insulin
administration. The blood glucose data versus time was graphed and
the data was analyzed with a two-way ANOVA with Bonferroni's post
hoc test to evaluate pair wise comparisons between test
formulations at each measurement time point. Experiment 1 indicated
that treatment with PG formulated insulin resulted in 24 hours of
good glycemic control (blood glucose level maintained between 50
and 130 mg/dl) for F-44 and about 18 hours for F-43 (FIG. 7). The
duration of glycemic control ranking was: F-44 (>24 hr) >F-43
(18 hr) >Humulin N (.about.12-24 hr) >Lantus (12 hr).
[0324] All four tested formulations exhibited similar onset of
action by achieving glycemic control within about 1 hour after the
subcutaneous injection. F-44 exhibited significantly lower blood
glucose at later time points (between 16 to 24 hrs) compared to the
three other formulas.
[0325] There was no significant blood glucose level difference
detected at early time points. In addition, F-43 was able to keep
blood glucose controlled for up to 18 hours after dosing. A
repeated study (Experiment 2) also confirmed the findings from
Experiment 1; that is, F-44 can control blood glucose up to 24 hrs
and F-43 can maintain low blood glucose level (<130 mg/dl) for
at least 18 hrs. In comparison, Lantus-treated rats achieved
glycemic control for only 12 hours. Humulin N showed the highest
animal-to-animal variability in blood glucose level.
Example 28
Prolonged (24 hr) and Peak-less Pharmacokinetic Profile of Human
Insulin Following Subcutaneous Injection of an Aqueous Gel
Containing Human Insulin (F-43)
[0326] The objective of this study was to evaluate F-43 (EXAMPLES
19 and 26) in STZ-induced type-I diabetes conscious Sprague Dawley
rats by comparing PK profiles (plasma insulin versus time) with a
marketed insulin drug (NPH Insulin/Humulin N).
[0327] Type I diabetes in Sprague Dawley rats was induced by
intravenous injection of STZ. Eight (8) rats (all having
STZ-induced type I diabetes, Sprague Dawley) were placed into two
treatment groups (F-43 and NPH). Small amounts of blood samples
were taken from the lateral tail vein of each animal and the blood
glucose levels were measured using a glucometer. 0.3 ml of whole
blood was taken from jugular vein and placed in EDTA-coated tubes
for plasma separation. The concentrations of human insulin in
plasma were measured using human insulin ELISA kit and RIA kits.
The animals were assigned to treatment groups such that there were
no significant differences between groups in body weight or blood
glucose level as measured by two-tailed student t test (P>0.05).
The animals were fasted for at least 12 hours and then the blood
glucose levels were measured just prior to administration of the
test formula.
[0328] The two formulations were administered subcutaneously at 20
IU/kg. Blood glucose levels were measured at pre, 1, 2, 4, 6, 8,
16, 20 and 24 hr post-insulin administration. Blood glucose and
insulin levels versus time was graphed and the data was analyzed
with a two-way ANOVA with Bonferroni's post hoc test to evaluate
pair wise comparisons between test formulations at each measurement
time point. The data indicated that treatment resulted in about 24
hr glycemic control (blood glucose level maintained at below 130
mg/dl) by F-43 or about 16 hr by NPH/Humulin N (FIG. 8B -lower
panel). The rats treated with F-43 exhibited a steady and prolonged
plasma insulin concentration profile between about 300 to 400
.mu.IU/mL by the ELISA or between 250 and 400 .mu.IU/mL by the RIA
method for about 24 hours, whereas the NPH-treated rats showed
continuous drop in plasma insulin concentration, which diminished
at about 24 hours. Moreover, treatment with F-43 resulted in a
"peak-less" PK profile (FIG. 8A--upper panel). Both tested
formulations exhibited similar onset of action, achieving glycemic
control within about the first hour after the SC
administration.
Example 29
Single-phase and Content Uniformity Study of F-43
[0329] The objective of this study was to demonstrate the
single-phase stability and the concentration uniformity of insulin
in F-43 (as in EXAMPLE 19) as studied using an insulin
pen-injector.
Procedure:
A) Day 1:
[0330] 1. Insert one pen injector cartridge vial filled with F-43
or Humulin N (NPH) into a pen injector (HumaPen Luxura by Eli Lilly
and Company). [0331] 2. Roll the pen back and forth 10 times and
turn the pen up and down 10 times to mix the content in the
cartridge vial. [0332] 3. Attach a Novofine 28 G.times.12 mm
needle. [0333] 4. Turn dose knob to 20 units and inject the content
into a small plastic vial, record the weight of the content
injected. Repeat the injection 9 times. Determine concentration of
insulin in each injection by HPLC analysis.
B) Day 2,7 and 14:
[0334] Repeat the Day 1 procedure except Step 2.
TABLE-US-00011 Results Insulin IU/g Insulin IU/g Sample ID Day 1
Day 2 Sample ID Day 1 Day 2 Day 7 Day 14 Humulin N, Inj #1 91.8
296.9 F43, Inj #1 104.1 100.6 113.8 97.1 Humulin N, Inj #2 95.4
265.5 F43, Inj #2 105.1 98.7 110.9 96 Humulin N, Inj #3 98.8 220.2
F43, Inj #3 104.1 100.2 97.6 95.9 Humulin N, Inj #4 96.4 167.1 F43,
Inj #4 101.8 102.8 98.1 97.3 Humulin N, Inj #5 101.9 110.4 F43, Inj
#5 100.9 104.9 96.6 97 Humulin N, Inj #6 111.6 74.9 F43, Inj #6
99.6 102.5 95.4 96.7 Humulin N, Inj #7 109.4 51.4 F43, Inj #7 102.6
103.7 98.2 96.6 Humulin N, Inj #8 110 26.1 F43, Inj #8 103.1 103.5
100.1 95.9 Humulin N, Inj #9 89.5 15.8 F43, Inj #9 103.4 104.4 97.4
95.6 Humulin N, Inj #10 90.6 21.3 F43, Inj #10 103.7 104.2 97.5
97.7 Avg 99.5 124.95 Avg 102.84 102.55 100.57 96.56 RSD 8.3 105.8
RSD 1.7 2.1 6.4 0.7 CV 8.4 84.7 CV 1.6 2.0 6.3 0.7
[0335] Conclusion: F-43 exhibited good content uniformity over time
even without implementing the pre-dosing mixing ritual that is
required for Humulin N. Humulin N on the other hand showed high
injection-to-injection variability between about 8% and 85%. A
separate study also shown that the F-43 remained uniform in its
insulin content after centrifugation at no less than 1000 RPM for
no less than 5 minutes.
Example 30
Preparation of an Aqueous Gel Containing Insulin Determir for Basal
Insulin Therapy
[0336] The Example is directed to preparation of an aqueous gel
containing insulin detemir, which is an insulin analog originally
created by Novo Nordisk. An aqueous gel is prepared in a
composition similar to F-43 as in EXAMPLE 19, wherein the
Recombinant Human Insulin is replaced with 100 to 400 IU/mL insulin
determir and the other components include POPC, sesame oil,
sucrose, m-cresol, phenol, methionine and water. The method
described in EXAMPLE 2 is used wherein insulin determir, is added
before or after the nanodispersion is formed. This composition is
intended for basal insulin therapy to provide glycemic control for
24 hours or longer.
Example 31
Preparation of an Aqueous Gel Containing NPH Insulin for Basal
Insulin Therapy
[0337] The Example is directed to preparation of an aqueous gel
containing NPH Insulin, which is also known as insulin isophane. An
aqueous gel is prepared in a composition similar to F-43 as in
EXAMPLE 19, wherein the Recombinant Human Insulin is replaced with
100 to 400 IU/mL NPH insulin and the other components include POPC,
sesame oil, sucrose, glycerol, m-cresol, phenol, methionine, sodium
phosphate and water. The method described in EXAMPLE 2 is used
wherein NPH is added after the nanodispersion is formed. This
composition is intended for basal insulin therapy to provide
glycemic control for 24 hours or longer.
Example 32
Preparation of an Aqueous Gel Containing botulism toxin type A for
an Aesthetic Medicine Indication
[0338] The Example is directed to preparation of an aqueous gel in
a composition similar to F-43 as in EXAMPLE 19, wherein the
Recombinant Human Insulin is replaced with 100 units/g (about 0.5
nanograms/g) of BOTOX.RTM. or purified botulinum toxin type A. The
method described in EXAMPLE 2 is used wherein purified botulinum
toxin type A is added before or after the nanodispersion is formed.
This composition is intended for the temporary improvement in the
appearance of moderate to severe glabellar lines associated with
corrugator and/or procerus muscle activity in adult patients
.ltoreq.65 years of age.
Example 33
PG Structural Characterization by Small Angle X-Rray Scattering
(SAXS)
[0339] Small-angle X-ray scattering (SAXS) is an analytical
technique that provides nanoscale information of particle or
lattice systems in terms of such parameters as averaged particle
sizes, shapes, distribution, and spacing etc. This information can
be used to quantitative determine the structural organization of
materials such as gels. For a comparison of two gel samples, SAXS
can show either differences in structures (particle size, stacking
etc.) or the degree of molecular order which differentiates an
ordered structure from a less ordered or random structures. SAXS
data is usually presented in diffractograms (FIG. 10). Peaks
observed in a SAXS diffractogram is measured for scattering angle
(on X-axis) which corresponds to lattice spacing in an ordered
structure and the scattering intensity (peak height) and sharpness,
which relate to degree of order.
[0340] Two gel samples containing insulin were prepared and tested
by SAXS. The first one is an aqueous gel of the present invention
in the F-43 composition as described in EXAMPLE 19 and the other
one contains the same components as in F-43 but was prepared by
combining all components and homogenizing extensively using a
high-speed mixer (Minibeadbeater). The second composition ("F-43 by
Direct Mixing") was not prepared using the invention method.
[0341] The SAXS data were collected in a helium chamber using a
Bruker M18XHF rotating anode generator operating at 50 kV and 50 mA
supplying a Cu K.alpha. (.lamda.=1.541838 .ANG.) radiation beam
that was collimated using a pinhole collimator. K.beta. radiation
was filtered out with a Ni filter. A Highstar multiwire detector
was used to collect the data. The samples were loaded without
modification into 0.9 mm borosilicate glass capillaries and sealed
with epoxy. The samples were mounted in the He chamber on an
automated goniometer at sample to detector distance of 64.55 cm. To
prevent scatter from air He gas was purged into the chamber for 1
hour and then each sample was collected for 7200 seconds. The data
were smoothed and integrated over the 360.degree. .chi. circle from
0.8 to 4.7.degree. 20 in 0.02 degree widths.
[0342] FIG. 10 shows diffractograms for both F-43 and F-43 by
Direct Mixing. Each sample showed two peaks. Provided below are the
lattice d spacing (d(.ANG.)) calculated by assuming n=1 for the
Bragg equation (n.lamda.=2d sin (0)) and degree of order or size of
"crystalline" domains based on the Scherrer equation:
( .tau. = K .lamda. .beta. cos .theta. ##EQU00001##
TABLE-US-00012 Degree of Order Sample Peak # d (.ANG.) (Scherrer
Crystalline domain size (nm)) F-43 by 1 70.00 42.3 (3) Direct
Mixing 2 34.70 16.0 (3) F-43 1 67.38 81.3 (5) 2 33.61 33.4 (5)
[0343] The SAXS data suggested that both samples have two phases
(peaks). Compared to F-43 by Direct Mixing, F-43 exhibits somewhat
different lattice d spacing in phase 1 (peak 1) and a greatly
increased Scherrer Crystalline domain size or degree of order in
both phases. This can be also seen in the sharpening of the peaks
in F-43 as compared to F-43 by Direct Mixing.
[0344] This SAXS study shows that F-43 PG material produced by the
method of this invention has an ordered structure and higher degree
of structural order than the same composition prepared another
method. The ordered structure found in the PG of the present
invention is consistent to the stacked balloon model as depicted in
FIG. 9 and is believed to be the reason for the surprisingly good
injectability of the PGs.
[0345] The contents of the articles, patents, and patent
applications, and all other documents and electronically available
information mentioned or cited herein, are hereby incorporated by
reference in their entirety to the same extent as if each
individual publication was specifically and individually indicated
to be incorporated by reference. Applicants reserve the right to
physically incorporate into this application any and all materials
and information from any such articles, patents, patent
applications, or other documents.
[0346] The inventions illustratively described herein may suitably
be practiced in the absence of any element or elements, limitation
or limitations, not specifically disclosed herein. Thus, for
example, the terms "comprising", "including," containing", etc.
shall be read expansively and without limitation. Additionally, the
terms and expressions employed herein have been used as terms of
description and not of limitation, and there is no intention in the
use of such terms and expressions of excluding any equivalents of
the features shown and described or portions thereof, but it is
recognized that various modifications are possible within the scope
of the invention claimed. Thus, it should be understood that
although the present invention has been specifically disclosed by
preferred embodiments and optional 10 features, modification and
variation of the inventions embodied therein herein disclosed may
be resorted to by those skilled in the art, and that such
modifications and variations are considered to be within the scope
of this invention as defined by the appended claims.
[0347] The invention has been described broadly and generically
herein. Each of the narrower species and sub generic groupings
falling within the generic disclosure also form 15 part of the
invention. This includes the generic description of the invention
with a proviso or negative limitation removing any subject matter
from the genus, regardless of whether or not the excised material
is specifically recited herein.
[0348] In addition, where features or aspects of the invention are
described in terms of Markush groups, those skilled in the art will
recognize that the invention is also thereby described in terms of
any individual member or subgroup of members of the Markush group.
Other embodiments are set forth within the following claims.
* * * * *