U.S. patent application number 11/635161 was filed with the patent office on 2007-05-03 for method for treating and/or preventing retinal diseases with sustained release corticosteroids.
This patent application is currently assigned to pSivida Inc.. Invention is credited to Paul Ashton, Hong Guo.
Application Number | 20070098760 11/635161 |
Document ID | / |
Family ID | 23044389 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070098760 |
Kind Code |
A1 |
Guo; Hong ; et al. |
May 3, 2007 |
Method for treating and/or preventing retinal diseases with
sustained release corticosteroids
Abstract
The present invention relates to a method for administering a
corticosteroid to a posterior segment of an eye. In the method, a
sustained release device is implanted to deliver the corticosteroid
to the eye. The aqueous corticosteroid concentration remains less
than vitreous corticosteroid concentration during release of the
corticosteroid from the device.
Inventors: |
Guo; Hong; (Belmont, MA)
; Ashton; Paul; (Boston, MA) |
Correspondence
Address: |
FISH & NEAVE IP GROUP;ROPES & GRAY LLP
ONE INTERNATIONAL PLACE
BOSTON
MA
02110-2624
US
|
Assignee: |
pSivida Inc.
Watertown
MA
|
Family ID: |
23044389 |
Appl. No.: |
11/635161 |
Filed: |
December 7, 2006 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10253825 |
Sep 25, 2002 |
|
|
|
11635161 |
Dec 7, 2006 |
|
|
|
09735636 |
Dec 14, 2000 |
6548078 |
|
|
10253825 |
Sep 25, 2002 |
|
|
|
09273548 |
Mar 22, 1999 |
6217895 |
|
|
09735636 |
Dec 14, 2000 |
|
|
|
Current U.S.
Class: |
424/428 ;
514/179 |
Current CPC
Class: |
A61K 31/573 20130101;
A61K 9/0051 20130101; A61P 35/00 20180101; A61P 9/00 20180101; A61P
27/02 20180101 |
Class at
Publication: |
424/428 ;
514/179 |
International
Class: |
A61K 31/573 20060101
A61K031/573; A61F 2/02 20060101 A61F002/02 |
Claims
1. A method for administering a corticosteroid to a posterior
segment of an eye, the method comprising the step of: implanting a
sustained release device to deliver the corticosteroid to the
vitreous of the eye and wherein aqueous corticosteroid
concentration is less than vitreous corticosteroid concentration
during release.
2. A method according to claim 1, wherein aqueous corticosteroid
concentration is about 0.002 .mu.g/ml to about 0.01 .mu.g/ml.
3. A method according to claim 2, wherein aqueous corticosteroid
concentration is about 0.01 .mu.g/ml to about 0.05 .mu.g/ml.
4. A method according to claim 1, wherein aqueous corticosteroid
concentration is non-toxic and is less than 0.05 .mu.g/ml.
5. A method according to claim 1, wherein the device releases
corticosteroid for about 1 month to about 10 years.
6. A method according to claim 5, wherein the device releases
corticosteroid for about 6 months to about 5 years.
7. A method according to claim 1, wherein the vitreous
corticosteroid concentration is therapeutic.
8. A method according to claim 1, wherein the vitreous
corticosteroid concentration is less than about 10 .mu.g/ml.
9. A method according to claim 1, wherein the corticosteroid is
selected from the group consisting of triamcinolone, dexamethasone,
fluocinolone, cortisone, prednisolone, flumetholone, and
derivatives thereof.
10. A method according to claim 1, comprising intravitreally
implanting the sustained release device.
11. A method according to claim 1, wherein a disease state to be
treated is selected from the group consisting of ocular
neovascularization, ocular inflammation and retinal
degeneration.
12. A method according to claim 1, wherein the sustained release
device releases the corticosteroid with pseudo zero order
kinetics.
13. A method according to claim 1, wherein the sustained release
device has a mean release rate of about 1 .mu.g/day to about 50
.mu.g/day of corticosteroid.
14. A method according to claim 13, wherein sustained release
device has a mean release rate of about 1 .mu.g/day to about 10
.mu.g/day of corticosteroid.
15. A method according to claim 1, wherein the sustained release
device releases only one drug.
16. An implantable, sustained release device for administering a
corticosteroid to a posterior segment of an eye, the device
comprising: a corticosteroid, wherein the device is configured to
provide sustained release of the corticosteroid to the vitreous of
the eye such that aqueous corticosteroid concentration remains less
than vitreous corticosteroid concentration during the release.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the field of controlled
pharmaceutical delivery, particularly to corticosteroids.
BACKGROUND OF THE INVENTION
[0002] Compounds classified as corticosteroids, such as
triamcinolone, can effectively treat some forms of
neovascularization such as corneal neovasularization. In general,
corticosteroids have been unsuccessful in treating
neovscularization of the posterior segment. In many patients, these
compounds cause undesirable side effects. These adverse affects
include elevations in intraocular pressure and the formation of, or
acceleration of, the development of cataracts. Elevations in
intraocular pressure are of particular concern in patients who are
already suffering from elevated intraocular pressure, such as
glaucoma patients. Moreover, a risk exists that the use of
corticosteroids in patients with normal intraocular pressure will
cause elevations in pressure that result in damage to ocular
tissue. Since therapy with corticosteroids is frequently long term,
i.e., several days or more, a potential exists for significant
damage to ocular tissue as a result of prolonged elevations in
intraocular pressure attributable to that therapy.
[0003] One approach to solving the foregoing problems has been to
search for specific compounds which are effective in treating
neovascularization without elevating intraocular pressure. Another
approach has been to administer corticosteroids in conjunction with
another drug to "block" or reduce the IOP elevating effects of the
corticosteroids or to treat IOP elevation separately with another
drug. A further approach has been to intravitreally inject
corticosteroids to treat ocular neovascularization.
[0004] There exists a need for an improved method for treating
and/or preventing retinal diseases with corticosteroids.
DISCLOSURE OF THE INVENTION
[0005] An object of the present invention is to provide a method
for treating and/or preventing ocular diseases which have
neovascularization as a component with corticosteroids without the
associated adverse side effects.
[0006] Additional objects, advantages and other features of the
invention will be set forth in the description which follows and in
part will become apparent to those having ordinary skill in the art
upon examination of the following or may be learned from the
practice of the invention. The objects and advantages of the
invention may be realized and obtained as particularly pointed out
in the appended claims.
[0007] According to the present invention, the foregoing and other
objects are achieved in part by a method for administering a
corticosteroid to a posterior segment of an eye, the method
comprising the step of:
[0008] implanting a sustained release device to deliver the
corticosteroid to the vitreous of the eye wherein aqueous
corticosteroid concentration is less than vitreous corticosteroid
concentration during release.
[0009] In accordance with the present invention, the foregoing and
other advantages are also achieved in part by an implantable,
sustained release device for administering a corticosteroid to a
posterior segment of an eye, the device comprising:
[0010] a corticosteroid, wherein the device is configured to
provide sustained release of the corticosteroid to the vitreous of
the eye such that aqueous corticosteroid concentration remains less
than vitreous corticosteroid concentration during the release.
[0011] Additional objects and advantages of the present invention
will become readily apparent to those skilled in this art from the
following detailed description, wherein embodiments of the
invention are described simply by way of illustrating of the best
mode contemplated in carrying out the invention. As will be
realized, the invention is capable of other and different
embodiments, and its several details are capable of modifications
in various obvious respects, all without departing from the
invention. Accordingly, the drawings and description are to be
regarded as illustrative in nature and not as restrictive.
BRIEF DESCRIPTION OF DRAWINGS
[0012] FIG. 1 shows the sustained release profile of a 2 mg
fluocinolone acetonide implant in buffer.
[0013] FIG. 2. shows the vitreous and aqueous levels of
fluocinolone acetonide after implantation of a sustained release
device.
DESCRIPTION OF THE INVENTION
[0014] The present invention provides a method for delivering a
therapeutic amount of a corticosteroid to the vitreous of an eye
but prevents toxic amounts of the corticosteroid from accumulating
in the aqueous. The method comprises the step of implanting a
sustained release device comprising a corticosteroid to the
posterior segment to deliver the corticosteroid to the vitreous
wherein aqueous corticosteroid concentration is less than vitreous
corticosteroid concentration during release of the
corticosteroid.
[0015] The present invention is particularly effective in treating
diseases of the retina, retinal pigment epithelium (RPE) and
choroid. These diseases include, for example, ocular
neovascularization, ocular inflammation and retinal degenerations.
Specific examples of these disease states include diabetic
retinopathy, chronic glaucoma, retinal detachment, sickle cell
retinopathy, senile macular degeneration, retinal
neovascularization, subretinal neovascularization; rubeosis iritis
inflammatory diseases, chronic posterior and pan uveitis,
neoplasms, retinoblastoma, pseudoglioma, neovascular glaucoma;
neovascularization resulting following a combined vitrectomy and
lensectomy, vascular diseases retinal ischemia, choroidal vascular
insufficiency, choroidal thrombosis, neovascularization of the
optic nerve, diabetic macular edema, cystoid macular edema, macular
edema, retinitis pigmentosa, retinal vein occlusion, proliferative
vitreoretinopathy, angioid streak, and retinal artery occlusion,
and, neovascularization due to penetration of the eye or ocular
injury.
[0016] Examples of corticosteroids useful in the present invention
include, for example, triamcinolone, dexamethasone, fluocinolone,
cortisone, prednisolone, flumetholone, and derivatives thereof.
[0017] By "sustained release device" it is meant a device that
releases drug over an extended period of time in a controlled
fashion. Examples of sustained release devices useful in the
present invention may be found in, for example, U.S. Pat. No.
5,378,475, and U.S. Pat. No. 5,773,019, and U.S. Ser. No.
08/919,221 filed on Aug. 28, 1997.
[0018] By "vitreous" of the eye, it is meant the vitreous or
vitreal cavity of the eye. By "aqueous" of the eye, it is meant the
aqueous humor of the eye.
[0019] In the present invention, a sustained release device is
implanted into the eye such that it delivers corticosteroid to the
posterior segment of the eye. In a preferred embodiment, the
sustained release device is implanted intravitreally. However, the
device may also be implanted in the choroidal space, sub-retinally,
or in the sclera. These methods of administration and techniques
for their preparation are well known by those of ordinary skill in
the art. Methods of administration and techniques for their
preparation are set forth in Remington's Pharmaceutical
Sciences.
[0020] The aqueous corticosteroid concentration remains less than
the vitreous corticosteroid concentration for substantially the
lifetime of the sustained release device. Thus, during release of
the corticosteroid, the aqueous corticosteroid concentration is
about 0.002 .mu.g/ml to about 0.01 .mu.g/ml, such as from about
0.01 .mu.g/ml to about 0.05 .mu.g/ml. Preferably, the aqueous
corticosteroid concentration is less than about 0.05 .mu.g/ml.
[0021] Is contrast, during release of the corticosteroid, the
vitreous corticosteroid concentration remains therapeutic, that is,
less than about 10 .mu.g/ml. The exact desired concentration
depends upon the disease and therapeutic index of the drug.
[0022] The sustained release device useful in the present invention
is any device which can be implanted to deliver corticosteroid to
the vitreous of the eye and can release a corticosteroid for a
sustained period of time, that is, for about 1 month to about 20
years, such as from about 6 months to about 5 years.
[0023] The sustained release device can be prepared to release the
corticosteroid by pseudo zero order kinetics with a mean release
rate of about 1 .mu.g/day to about 50 .mu.g/day, such as, about 1
.mu.g/day to about 10 .mu.g/day.
[0024] The following non-limiting examples are given by way of
illustration only.
EXAMPLE 1
[0025] Sustained release fluocinolone acetonide devices were
implanted into the vitreous of 4 rabbits while animals in the
control group received a sham operation. After implantation, all
rabbits received a sub-retinal injection of gelatin microspheres
releasing basic fibroblast growth factor. All control animals
developed neovascularization while 3/4 of the implant group showed
no evidence of neovascularization. No animals showed any indication
of ocular or systemic steroid-induced toxicity.
EXAMPLE 2
[0026] Animals received intravitreal fluocinolone acetonide
implants and were sacrificed at 1 month, 4 months, and 11 months.
Samples of the vitreous and aqueous were collected for analysis by
HPLC. Analysis was performed using a fully automated Hitachi HPLC
system. The mobile phase was 40% acetonitrile buffered to a pH of
4.0. The flow rate was 1.0 ml/min with an Axxion C-18 column (25
cm.times.4 mm.times.5 .mu.m) and UV detection at 238nm.
Intravitreal levels were found to be relatively constant throughout
the study (0.1-0.2 .mu.g/ml) while no steroid was detected in the
aqueous humor (limit of detection 0.02 .mu.g/ml).
DETAILED DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 shows the sustained release profile of a 2 mg
flucinolone acetonide implant in buffer over 100 days. The mean
release rate was 2.1+/-0.26 .mu.g/day.
[0028] FIG. 2 shows the vitreous and aqueous levels of fluocinolone
acetonide after implantation of a sustained release device. Animals
were sacrificed at 4 weeks, 20 weeks, and 1 year. FIG. 2 shows that
therapeutic levels are maintained in the vitreous while drug levels
in the aqueous humor were below the detection limit of the
assay.
[0029] In the previous descriptions, numerous specific details are
set forth, such as specific materials, structures, chemicals,
processes, etc., in order to provide a better understanding of the
present invention. However, the present invention can be practiced
without resorting to the details specifically set forth. In other
instances, well-known processing structures have not been described
in detail in order not to unnecessarily obscure the present
invention.
[0030] Only the preferred embodiment of the invention and but a few
examples of its versatility are shown and described in the present
disclosure. It is to be understood that the present invention is
capable of use in various other combinations and environments and
is capable of changes or modifications within the scope of the
inventive concept as expressed herein. All patents, patent
applications and publication cited herein are incorporated by
reference in their entirety.
* * * * *