Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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OCULAR CYCLOSPORIN COMPOSITION
The present invention relates to a method and
composition for increasing tear production by the
topical administration of cyclosporin to the patient's
eyes.
BACKGROUND OF THE INVENTION
The exposed part of a normal eye is covered by a
continuous thin tear film which is important for the
well-being of the corneal and conjunctival epithelium
and provides the cornea with an optically high quality
surface. In addition, the aqueous part of the tear film
acts as a lubricant to the eyelids during blinking of
the lids. Certain enzymes contained in the tear fluid,
for example immunoglobulin A, lysozyme and beta lysin,
also have bacteriostatic properties.
The lacrimal apparatus consists of the secretory
system (the source), the distribution system and the
excretory system (the sink). In the secretory system,
the bulk of the tear film, the aqueous tears, are
supplied by the main and accessory lacrimal glands.
The continuous production and drainage of aqueous tears
is important in maintaining the corneal and conjunctival
epithelium in a moist state, in providing nutrients for
-~ epithelial respiration, in supplying bacteriostatic
agents and in cleaning the ocular surface by the
flushing action of tear movement.
Abnormalities of the tear film include an absolute
or partial deficiency in aqueous tear production, called
keratoconjunctivitis sicca or KCS. In relatively mild
cases, the main symptom of KCS is a foreign body
sensation or a mild nscratchinessn. This can develop
t ~
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into a constant, intense burning or irritative sensation
which can be debilitating to the patient. M o r e
severe forms lead to the development of filamentary
keratitis, a painful condition characterized by the
appearance of numerous strands or filaments attached to
the corneal surface. Recent evidence suggests that
these filaments represent breaks in the continuity of
the normal corneal epithelial cells. The shear created
by lid motion pulls these filaments, causing pain.
Management of this stage of KCS is very difficult.
A frequent complication of KCS is secondary
infection. Several breakdowns in the eye's normal
defense mechanism seem to occur, presumably attributable
to a decrease in the concentration of antibacterial
lysozyme in the aqueous tears of a patient suffering
from KCS.
Although KCS can develop in the absence of any
other overt systemic abnormality, there is a frequent
association of KCS with systemic disease. KCS can occur
as part of a larger systemic involvement known as
Sjogren's syndrome which is characterized by dry eyes,
dry mouth, and arthritis.
Histologically in KCS (as part of Sjogren's
syndrome or in isolation), the initial changes seen in
the lacrimal gland are those of focal lymphocytic and
plasma cell infiltrates associated with degeneration of
glandular tissue. These changes resemble those seen in
autoimmune disease in other tissue, giving rise to the
speculation that KCS has an autoimmune basis.
Sjogren's syndrome is recognized as an exocrine
glad dysfunction. Characteristically, the lacrimal
glands show a mononuclear-cell infiltration that
3 1 335566
ultimately leads to destruction of the glandular
structure.
Conventional treatment of KCS is symptomatic.
Normally, aqueous-deficient dry eye states are treated
by supplementation of the tears with artificial tear
substitutes. However, relief is limited by the
retention time of the administered artificial tear
solution in the eye. Typically, the effect of an
artificial tear solution administered to the eye
dissipates rapidly, within about thirty to forty-five
minute~. Th- effect of ~uch product~, while ~oothing
initially, does not last long enough. The patient is
inconvenienced by the necessity of repeated
administration of the artificial tear solution in the
eye as needed to supplement the normal tears. Moreover,
such treatment merely acts to alleviate the symptoms of
the dry eye state and does not cure any underlying
disorders or causes of the dry eye state.
The systemic use of corticosteroids has been
advocated to treat these conditions. However, the merit
of systemic corticosteroids in dry eye states has not
been established. In most dry eye cases the hazards of
long-term use of antiinflammatory agents would seem to
outweigh their potential merit. It has also been
suggested to administer orally a dilute solution of
pilocarpine to stimulate the autonomic nervous system
to effect increased aqueous tear production. This
method of treatment has not met with universal favor
because of the unpleasant side effects of ingested
pilocarpine.
Surgical procedures have also been suggested in
the management of dry eye states. Where there has been
4 1 335566
significant conjunctival destruction, mucous membrane
transplants have been advocated. It has also been
suggested that parotid (saliva) duct transplantation can
be useful in the management of dry eyes. However, since
surgical alterations to combat dry eye conditions
constitute such a drastic remedy and the benefit
resulting from these alterations is questionable, these
methods are usually used only as a last resort.
Cyclosporin is a metabolite isolated from the
culture broths of the fungal species Tolypocladium
inflatum Gams. A neutral, hydrophobic cyclic peptide
composed of eleven amino acid resides, cyclosporin
includes a previously unknown N-methylated amino acid
composed of nine carbon atoms. Wenger, Synthesis of
Cyclosporin and Analoques, pp. 14-25 in CYclosPorin A
1, Grune & Stratton, Inc. (New York 1983). A number of
additional cyclosporins (B, C, D, E, and G) have been
reported since the first cyclosporin was isolated (CsA).
As described in U.S. Patent No. 4,117,118 issued
September 26, 1978 to Harri et al., cyclosporin is
readily soluble in most of the usual organic solvents
and practically insoluble in petroleum ether and water.
As distributed by Sandoz Ltd., Basel, Switzerland, under
the tradename Sandimmune, cyclosporin for oral
administration is dissolved in olive oil for further
dilution with food and in polyoxyethylated castor oil
and ethanol for intravenous injection.
Cyclosporin A was first proposed for use as an
antifungal agent, but its immunosuppressive effects were
found to be more marked than its antifungal potential.
A potent immunosuppressive agent, cyclosporin is used
to prolong survival of allogeneic transplants involving
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skin, heart, kidney, pancreas, bone marrow, small
intestine and lung. The exact mechanism of action is
not known but experimental evidence suggests that the
effectiveness of cyclosporin is due to specific and
reversible inhibition of immunocompetent cells,
primarily T-helper cells. Lymphokine production, gamma
interferon production and release of interleukin-2 or
T-cell growth factor are also inhibited by cyclosporin.
Cyclosporin's immunosuppressive properties have
led to its use in immune system related diseases. For
example, U.S. Patent No. 4,649,047 describes a method
for the treatment of phacoanaphylactic endophthalmitis
and uveitis in the anterior or posterior segment of an
eye wherein cyclosporin is topically administered to
the eye. In other ophthalmic applications, cyclosporin
has been used topically only for the treatment of
external (e.g., corneal) eye diseases.
BenEzra et al., Amer. J. Ophthalmol. 101: 278-282
(1986), describe the effect of 2% cyclosporin eyedrops
on severe vernal keratoconjunctivitis. Severe vernal
keratoconjunctivitis is a seasonal allergic disorder
unrelated to tear deficiency.
Hunter et al., Clin. Exp. Immunol. 45: 173-177
(1981) describe the topical administration of
cyclosporin in a rabbit model of corneal graft rejection
with positive results.
Boisjoly et al., Arch. Ophthalmol. 102: 1804-1807
(1984), have reported that topical application of
cyclosporin had a beneficial prophylactic effect towards
the treatment of severe herpetic stromal keratitis.
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Mosteller et al., Investiqative Ophthalmol. Supp.
25, 3: 38 (1984), disclose treating corneal allograft
rejection in rabbits by applying a single dose of a 10%
Cyclosporin A ointment in the lower cul-de-sac of the
eyelids.
Cyclosporin has also been used systemically in
other ophthalmic applications, where the disease being
treated is not limited to the eye surface. For example,
Nussenblatt et al., Amer. J. Ophthalmol. 96: 275-282
(1983), have reported clinical improvement in some
patients with noninfectious posterior uveitis following
systemic treatment with cyclosporin.
Cyclosporin is primarily administered orally or
by injection. Unfortunately, cyclosporin used
systemically has been associated with a high incidence
of renal toxicity (kidney failure), some cases of
hepatotoxicity, increased incidence of lymphoid tumors
and increased incidence of opportunistic infections.
Cyclosporin is only slightly less toxic than other
immunosuppressive agents such as cytoxan or
aziothioprine. The systemic side effects of cyclosporin
are so severe and so common that they limit its use to
life-threatening or in some cases severe sight-
threatening disease. Finally, systemic application of
cyclosporin is limited by its prohibitive cost.
As described in U.S. Patent No. 4,649,047 issued
March 10, 1987 to Kaswan, topical administration of
cyclosporin is useful in the treatment of a variety of
immune mediated disorders of the eye, including uveitis
and phacoanaphylactic endophthalmitis. This is also the
preferred mode of administration to avoid the
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undesirable side effects and cost of systemic
administration.
To date, there has been no suggestion to treat a
glandular dysfunction, a lacrimal gland dysfunction or
an aqueous-deficient dry eye state with a cyclosporin,
either topically or systemically.
Although cyclosporin has been topically
administered in a variety of vehicles including arachis
oil, a commercia-lly available ointment base, and castor
oil, the conventional carrier is olive oil.
Unfortunately, topical administration of cyclosporin in
olive oil to the eye of either humans or dogs is
frequently accompanied by a burning sensation, pain,
and redness. In some cases, other side effects have
been observed including lid edema and periocular
alopecia (hair loss around the eye). Similar problems
have occurred with topical ophthalmic use of cyclosporin
in the other vehicles. Studies have now demonstrated
that these unpleasant side effects are due to the
carrier, not to the cyclosporin. Unfortunately,
cyclosporin is of very limited solubility and the number
of acceptable carriers for ophthalmic use is limited.
It is therefore an object of this invention to
provide a method of increasing tear production for a
normal or tear-deficient eye, regardless of cause.
It is another object of this invention to provide
a cyclosporin-based treatment of lacrimal gland
dysfunction without the accompanying adverse
physiological responses and economic difficulties
associated with systemic cyclosporin treatments.
It is another object of the present invention to
provide a composition containing an effective
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concentration of cyclosporin for topical ophthalmic use
which does not cause burning, redness or irritation.
It is a still further object of the present
invention to provide a composition for topical
ophthalmic use which is stable upon storage.
It is still another object of the present
invention to provide a composition for topical
ophthalmic use which promotes normal healing of the
epithelial surface of the eye.
SUMMARY OF THE INVENTION
The present invention is directed to a method of
treating a dry eye state in a patient by administering
a cyclosporin topically to the patient's eye. The
treatment is useful regardless of the cause of the dry
eye, and includes treatment of autoimmune dysfunction
of the lacrimal glands. The treatment is also useful
in the enhancement or restoration of normal tear
production, and normal healing of the surface of the
eye.
The preferred composition for topical
administration to the eye consists of cyclosporin
dissolved in corn oil. The composition may further
include antioxidants, lubricants, antibiotics,
antifungals, antivirals, pilocarpine, vasoconstrictors,
surfactants, wetting agents, anti-inflammatory agents
(i.e. corticosteroids), preservatives, mucolytic agents
(i.e. bromhexine, acetylcysteine), as well as other
compounds.
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The most preferred composition is 2% cyclosporin,
1 mole % alpha tocopherol and 0.005% methyl paraben in
corn oil.
Brief Description of th- Drawings
Figure 1 is a graph demonstrating the effect of
topical cyclosporin on lacrimination (STT mm/min) over
time (days) in twelve normal male beagle dogs; following
three days of baseline measurement with no treatment,
six dogs were treated with 2% cyclosporin in olive oil
applied topically two times daily, and six dogs were
treated with placebo (olive oil) applied topically two
times daily. The STT were determined twice daily in the
cyclosporin treated dogs ( ~ ) and in the
olive oil treated dogs ( --- ). Following 7 days
all dogs were crossed over into the opposite treatment
groups for an additional three days.
Figure 2 is a comparison of the appearance of the
eye of a dog suffering from keratoconjunctivitis sicca
before (Figure 2A) and after (Figure 2B) treatment for
four weeks with 2% cyclosporin.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a method of
treating tear-deficient dry eyes due to autoimmune
disease or of unknown etiology which includes the step
of administering a cyclosporin topically to the
patient's eye. The invention includes a corn oil based
cyclosporin composition which provides greatly enhanced
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benefits when applied topically to the eye over previous
cyclosporin compositions.
Despite the apparent similarities in chemical
structure, studies demonstrate the significant
differences in comfort and incidence of side effects
between cyclosporin in previously described carriers
such as olive oil and cyclosporin in corn oil, both with
and without preservative and antioxidant. These studies
also establish that topically applied cyclosporin can
be used to promote or effect normal healing and prevent
or reverse scar formation on the ocular surface.
In accordance with the present invention, the
cyclosporin may be used in any efficacious
concentration, e.g., 0.01 to saturation (e.g., up to 50
weight percent of a cyclosporin) in a pharmaceutically
acceptable excipient. Concentrations of 1.1 to 20
weight percent of a cyclosporin are preferred. Although
the preferred vehicle is corn oil, as described below,
other pharmaceutically acceptable excipients are, for
example, animal oil, vegetable oil, appropriate organic
or aqueous solvents, artificial tear solutions in which
the cyclosporin is soluble, and natural or synthetic
polymers or appropriate membranes.
Examples of these pharmaceutically acceptable
excipients are olive oil, arachis oil, castor oil,
mineral oil, petroleum jelly, dimethyl sulfoxide,
chremophor~ Miglyo~ 182 (commercially available from
Dynamit Nobel Kay-Fries Chemical Company, Mont Vale,
New Jersey), alcohol (e.g., ethanol, n-propyl alcohol
or iso-propyl alcohol), liposomes or liposome-like
products, silicone fluids and mixtures thereof.
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Examples of artificial tear excipients which can
be advantageously used in the practice of this invention
are isotonic sodium chloride, cellulose ethers such as
hydroxypropylmethylcellulose and hydroxyethylcellulose,
polyvinyl alcohol and other commercially available
artificial tear solutions. An example of a useful
polymeric excipient is polyoxyethylated castor oil.
Examples of pharmaceutically acceptable membranes which
can advantageously be used in the practice of this
invention are: microdone, an artificial lipid membrane,
polyvinylalcohol, or methylcellulose.
Cyclosporins which are useful in the practice of
the present invention include both natural or synthetic
cyclosporins. Cyclosporin A is preferred in the
practice of the present invention. Other forms of
cyclosporins (e.g., analogs and isomers such as
Cyclosporins B, C, D, E, and H) may also be used.
Mixtures of different cyclosporins may be used.
In the preferred method of treating a specific
antigen mediated immune response in a patient having
more than one involved site of the immune mediated
response, the cyclosporin is applied locally to each
involved site. For example, where only one eye appears
to suffer from immune mediated KCS, both eyes should be
treated. Surprisingly, unless each involved site is
treated with cyclosporin, no appreciable benefit is
obtained from cyclosporin treatment at any one of the
sites, i.e., if only the affected eye is treated, little
benefit of the cyclosporin is obtained. This suggests
that locally administered cyclosporin interferes with
and blocks the afferent immune recognition of the
specific antigen which triggers the immune mediated
1 335566
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response. Unless each of the sites wherein the specific
antigen occurs is treated with the cyclosporin, T-cell
antigen signaling occurs continuously in the untreated
site causing local lymphokine production that triggers
a cascading systemic immune response that adversely
affects both the treated and untreated sites.
In other words, local administration of
cyclosporin acts to inhibit the continuous afferent
immune response, for example within an eye, when
antigens placed in the eye are associated with
intraocular MHC antigen bearing accessory cells and are
presented to T-cells. However, if an untreated eye or
a distal skin graft is used to initiate antigen
recognition, an afferent immune response begins at the
site distal to the treatment site, T-cells are
activated, lymphokines produced, and the systemic immune
response proceeds to an efferent immune response
affecting both eyes.
Thus, in any experiment in which an intrasubject
control eye is used, local therapy in one eye will have
diminished effect unless it is given in such quantity
as to produce systemic immuno-suppression. Moreover,
when treating an immune mediated response which exists
to a much greater degree at one site of a patient, such
as in or near one eye of the patient, than at another
site of the patient, such as in the other eye of the
patient, so as to be apparent at only the one site, the
cyclosporin is advantageously administered locally in
a therapeutically effective amount to each of the sites.
An immune mediated response which appears to exist in
only one eye of a patient is advantageously treated by
administering a therapeutically effective amount of a
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cyclosporin locally to both eyes of the patient to
achieve maximal benefit.
If administered locally to each of the sites of
the patient affected by the immune mediated response,
cyclosporin can be used advantageously to treat a
variety of immune mediated disorders. Ocular diseases
which are successfully treated in animal models by local
administration of cyclosporin to each site of the
patient effected by the immune mediated response include
immune-mediated melting ulcers in cats and dogs, chronic
neovascularization and proliferative keratitis in cats
and dogs, stromal keratitis subsequent to ulcerative
Herpes keratitis in cats, pigmentary keratitis in dogs
and KCS in dogs.
Numerous advantages accrue with the practice of
the present invention. The method of the present
invention is useful in that it can locally prevent
activation of a pre-systemic response. Topical
administration of a cyclosporin into a patient's tear
deficient eye increases tear production in the eye.
Thus, such treatment further serves to correct corneal
and conjunctival disorders exacerbated by tear
deficiency and KCS, such as corneal scarring, corneal
ulceration, inflammation of the cornea or conjunctiva,
filamentary keratitis, mucopurulent discharge and
vascularization of the cornea. Furthermore, cyclosporin
directly decreases the immune response of granulation
and neovascularization in the cornea.
Further objects of this invention, together with
additional features contributing thereto and advantages
accruing therefrom, will be apparent from the following
examples of the invention.
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Ex~mple 1: Effectiveness and distribution of topical
cyclosporin.
Topical administration to a patient's eye has
surprisingly been found to be an excellent method for
providing a cyclosporin to the lacrimal glands of the
patient to treat KCS. Additionally, since by its very
nature topical administration does not require
cyclosporin dispersion throughout the patient's system
as is the case with systemic administration, the present
invention provides a means for directing cyclosporin to
the desired location without the accompanying high risk
of adverse responses and high cost associated with
systemic treatments.
Cyclosporin concentration has been determined for
various eye compartments and tissues surrounding the eye
after bilateral topical administration of cyclosporin
to the eyes of three rabbits. The cyclosporin was
administered in each of the rabbits' eyes in drops
(approximately 17 microliters) of 2% radiolabelled
cyclosporin in an olive oil solution applied every 15
minutes for 6 applications, followed by a period of two
hours to allow for absorption. The rabbits were then
euthanized and the eyes and surrounding tissue
enucleated and frozen. The eyes and surrounding tissue
were dissected into their component parts. These were
then digested in collagenase and the resulting solutions
analyzed by liquid scintillation counting for
cyclosporin content. The following average cyclosporin
concentrations were measured:
Accessory lacrimal gland: 2850 ng of
cyclosporin/gram of tissue;
Periorbital fat: 800 ng/gram;
-lS- 1 3 3 5 5 6 6
Cornea: 4700 ng/gram;
Iris: 1200 ng/gram;
Retina: 50 ng/gram;
Aqueous humor: 30 ng/gram;
Vitreous humor: 30 ng/gram;
Anterior sclera: 3150 ng/gram; and
Posterior sclera: 1550 ng/gram.
Example 2: Comparison of treatment of dry eye with ~nti-
inflammatory steroid ~nd cyclosporin.
lo A one year old standard female Poodle with
conjunctivitis exhibited mild aqueous tear deficiency
in both eyes. The dog had a Schirmer tear test value
of 15 mm/minute in the right eye and 10 mm/minute in
the left eye.
The Schirmer tear test is a test of aqueous tear
production. The test depends upon observing the extent
of wetting of a strip of filter paper placed over the
lower lid of an eye for a specified time. Standardized
strips are commercially available. The strip is folded
at a notched marking and is then placed over the edge
of the lateral one-third of the eyelid. The strip is
usually left in place for a period of time while the
patient looks straight ahead in dim light.
The degree of wetting of the paper is measured in
mm from the notch. For human patients, a normal end
point is 5 mm of wetting at five minutes. For canine
patients, the normal tear production is 14 to 20 mm of
wetting at one minute.
The dog was originally treated with dexamethasone
by topical administration in both eyes four times daily.
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Although initially somewhat effective, treatment was
subsequently discontinued and the same dog at
approximately six years old still exhibited
conjunctivitis in both eyes and had a Schirmer tear test
value of 3 mm/minute in both eyes. Topical
dexamethasone was then applied to both eyes twice daily
for nine weeks without benefit.
The dog was then treated by topical application
of 2% cyclosporin in an olive oil solution in both eyes
once daily without any other medications. After ten
days, the dog showed markedly increased tear production
and had a Schirmer tear test value of 22 mm/minute in
the right eye and 8 mm/minute in the left eye.
The treatment by topical application of 2%
cyclosporin in an olive oil solution in both eyes once
daily was continued for an additional three weeks. At
this time, the dog exhibited plentiful aqueous tear
production and the treatment was stopped for one week.
After the one week, the dog had a Schirmer tear test
value of 10 mm/minute in the right eye and 9 mm/minute
in the left eye.
At this time, the treatment by topical application
of 2% cyclosporin in an olive oil solution in both eyes
once daily was reinstituted and continued for six days.
After the six days, the dog had a Schirmer tear test
value of 22 mm/minute in the right eye and 16 mm/minute
in the left eye.
In this case, a dog with chronic tear deficiency
in which prior use of corticosteroids failed to improve
tear secretion showed a surprising increase in tear
production with cyclosporin treatment. The increased
tear production continued only while cyclosporin therapy
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continued. When the treatment was stopped for a week,
the eyes again became tear deficient. However, tear
production increased to normal levels after the
treatment was restarted.
Ex_mple 3: Treatment of dry eye ~nd enhancement of
corne~l healing with topical cyclosporin
treatment.
An eight year old male Lhasa Apso had a four year
old cat scratch in his left eye and an active 4 mm
stromal ulcer in his right eye. An ocular examination
of the dog showed conjunctivitis in both eyes with
mucopurulent discharge, diffuse irregular corneal
surfaces, pigment formation and neovascularization in
the cornea of the left eye. The Schirmer tear test
values were 12 mm/minute in the right eye and 3
mm/minute in the left eye.
The dog was treated with topical administration
to both eyes of 2% cyclosporin in an olive oil solution
once daily, neosporin twice daily and ophthalmic
petrolatum. After five days, the Schirmer tear test
values were 22 mm/minute in the right eye and 23
mm/minute in the left eye. In addition, the ulcer in
the right eye was healed to 2 mm and the left eye was
assessed to have decreased vascularization.
In this case, cyclosporin increased tear
production significantly in a short period of time.
Moreover, cyclosporin, unlike corticosteroids, did not
retard corneal healing nor activate corneal collagenase.
Accordingly, cyclosporin can be used in eyes having
active corneal ulcers.
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Example 4: Comparison of tre~tment of dry eye with
pilocarpine alone and in combination with
cyclosporin.
A six year old male English Bulldog with a long
history of KCS had Schirmer tear test values of 2
mm/minute in the right eye and 3 mm/minute in the left
eye.
The right eye was neovascularized over the entire
cornea. No intraocular detail could be visualized
through the opaque cornea. The cornea was grossly thick
and irregular in surface. The left eye had
neovascularization over about half of the cornea, mostly
axially.
The dog was treated with three drops of 2%
pilocarpine by mouth. After two hours, the Schirmer
tear test values were 0 mm/minute in the right eye and
10 mm/minute in the left eye.
The dog was then treated with 2~ cyclosporin in
an olive oil solution administered topically to both
eyes once daily and three drops of 2% pilocarpine
administered by mouth twice daily. After twelve days,
the Schirmer tear test values were 10 mm/minute in the
right eye and 15 mm/minute in the left eye.
In this case, while pilocarpine alone increased
tear production in the left eye from a Schirmer tear
test value of 3 mm/minute to 10 mm/minute, pilocarpine
did not increase tear production in the right eye. Use
of cyclosporin with pilocarpine increased tear
production to a Schirmer tear test value of 15 mm/minute
in the left eye and from 0 mm/minute to 10 mm/minute in
the right eye. The use of cyclosporin markedly
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increased tear production over the use of pilocarpine
alone.
Example 5: Correction of dry eye ~nd restor~tion of
normal vision by topic~l treatment with
cyclosporin.
A seven year old Miniature Poodle had a history
of severe KCS of six to seven months duration.
Treatment with artificial tears six times daily did not
affect the apparent blindness.
The dog showed marked mucopurulent discharge in
both eyes. The Schirmer tear test values were O
mm/minute in both eyes. The dog's corneas were
thickened and neovascularized with an irregular surface.
No intraocular detail could be visualized through the
opaque corneas.
The dog was treated with one drop of 2%
pilocarpine by mouth two times daily and ophthalmic
petrolatum four times daily. After two weeks, the
Schirmer tear test values were still O mm/minute in both
eyes. The corneal vascularity and scarring remained
dense and the anterior chambers of the dog's eye were
not visualizable.
The dog was then treated with 2% cyclosporin in
an olive oil solution administered topically in both
eyes once daily and two drops pilocarpine administered
by mouth twice daily.
After two weeks, the Schirmer tear test values
were 8 mm/minute in the right eye and 6 mm/minute in
the left eye. Although corneal vascularization and
scarring remained, the iris and lens could be evaluated,
there was no mucoid discharge in either eye as
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previously and the KCS was assessed as medically
improved.
After similar treatment for another two months,
the Schirmer tear test values were 11 mm/minute in the
right eye and 17 mm/minute in the left eye. The dog's
eyes had minimal corneal vascularization and minimal
scarring.
In this case, although the dog was treated
initially with pilocarpine, pilocarpine alone is not
known to cause such a drastic improvement in tear
production. After treatment with cyclosporin, the dog
improved from no tear flow in either eye to normal tear
production in both eyes. The dog improved from blinding
corneal inflammation to very mild corneal pigmentation
in both eyes. Treatment with cyclosporin markedly
increased tear production and allowed the dog to return
to normal vision.
Example 6: Stimul~tion of tearing in normal dogs.
Studies were conducted on the effect of applying
topical 2% cyclosporin in olive oil to the eyes of
normal dogs. The results are shown in Figure
comparing the effect of topical cyclosporin on
lacrimination in six normal male beagle dogs, before
and after several days of olive oil therapy alone. In
both studies, no treatment was given on days 1 to 3 to
establish a baseline. On days 4-10, as graphed by the
triangles, one drop of olive oil was administered twice
daily (BID) to each eye. On days 11-13, one drop of 2%
cyclosporin in olive oil was administered twice daily.
A significant increase in tearing was observed. On days
4-10, as graphed by the squares, one drop of 2%
cyclosporin in olive oil was administered twice daily.
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On days 11-13, one drop of olive oil was applied to each
eye twice daily. The significant increase in tearing
observed over days 4-10 persisted through days 11-13 in
the absence of cyclosporin treatment.
The data conclusively demonstrate that topically
applied cyclosporin increases glandular function, i.e.,
lacrimination, in normal eyes.
Since cyclosporin has very low solubility in most
solutions which can be administered to the eye, the
cyclosporin in the majority of studies on the efficacy
of topical administration of cyclosporin has been
suspended in olive oil. Unfortunately, controlled
studies comparing olive oil alone and in combination
with cyclosporin demonstrate that the vehicle, the olive
oil, produces redness and burning. In animals, pain is
evidenced by the animal holding its eyes shut. In
approximately 5 to 10% of approximately 1000 months of
treatment (based on number of bottles of 2% cyclosporin
dispensed for veterinary use where one bottle is
sufficient for treatment of an animal twice daily for
about one month), other side effects were observed,
including lid edema, corneal surface irregularities, and
periocular alopecia.
The present invention includes the surprising
discovery that corn oil can be substituted for olive
oil as the vehicle for topical administration of
cyclosporin to the eye to avoid the undesirable side
effects due to the use of the olive oil. Over 3000
bottles of 2% cyclosporin have now been dispensed for
treatment of animals twice daily without any apparent
side effects for periods of time up to four months.
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Additives to the corn oil which enhance stability
of the cyclosporin solution include antioxidants such
as alpha tocopherol and preservatives such as methyl
paraben. Other antioxidants are known to those skilled
in the art. There are some indications that alpha
tocopherol (Vitamin E) may also have beneficial effects
on the eye since oxidative radicals increase
inflammatory damage. Preliminary clinical observations
on the protective action of oral administration of
vitamins A and E on the corneal epithelium were recently
published by Gerhardinger, et al., in Acta Vitaminol.
EnzYmol. 7(Supp),71-74 (1985). Other compounds which
may be added to the cyclosporin solution include
emollients, viscosity modifying agents, antioxidants,
preservatives, antibiotics, antifungals, antivirals,
lubricants, surfactants, vasoconstrictors, DMSO,
parasympathomimetics, cholinergics, neurotransmitters,
lacrimogenic agents, substance P agonists, substance P
antagonists, mucolytics, prostaglandin antagonists,
lipogenase inhibitors, cyclooxygenase inhibitors,
antiinflammatories, oxygen scavengers, hydrating agents,
and epitheliotropic agents. Specific examples, in
addition to alpha tocopherol and methyl paraben,
include vitamin A, retinoic acid, pilocarpine,
hyaluronic acid, polyvinyl alcohol, methylcellulose,
eledoisin, physalaemin, bromhexine, mucosolvan,
acetylcysteine, indomethacin, and corticosteroids.
The most preferred formulation at this time for
topical ophthalmic use consists of 2~ cyclosporin, 1
mole % alpha tocopherol and 0.005% methyl paraben.
However, cyclosporin solutions can be prepared of
between approximately 0.01% by weight and saturation,
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approximately 20% by weight. Unless otherwise
specified, all percentages of compounds herein are by
weight.
Although the usual means of administration of the
compound is by administration of cyclosporin drops to
the surface of the eye, delayed or prolonged release of
the cyclosporin at a selected site can also be achieved
by encapsulating the cyclosporin-oil mixture within a
polymeric implant, liposomes, or microcapsules. Methods
lo for making polymeric implants for ocular use are taught
by U.S. Patent No. 3,960,150 to Hussain et al. Both
non-degradable and biodegradable polymers can be used,
including polyethylene, polystyrene, polypropylene,
polyanhydrides, polyorthoester, polylactic acid, and
polyglycolic acid. Methods for encapsulating materials
within liposomes are taught by PCT/US85/00220
publication WO 85/03640 29 August 1985 by the Liposome
Company. Methods for encapsulation of biological
material within microcapsules for implantation are
taught by U.S. Patent No. 4,352,883 to Lim. Other
suitable methods and materials are known to those
skilled in the art.
The following non-limiting examples demonstrate
the efficacy and advantages of topical cyclosporin in
corn oil for treatment of immune disorders, enhancement
or restoration of tear production, and enhancement or
effecting of normal healing of the surface of the eye.
Example 6: Stimulation of tearing in normal dogs.
Studies were conducted on the effect of applying
topical 2% cyclosporin in olive oil to the eyes of
normal dogs. The results are shown in Figure
comparing the effect of topical cyclosporin on
-24- 1 3 3 5 5 6 6
lacrimination in six normal male beagle dogs, before
and after several days of olive oil therapy alone. In
both studies, no treatment was given on days 1 to 3 to
establish a baseline. On days 4-10, as graphed by the
triangles, one drop of olive oil was administered twice
daily (BID) to each eye. On days 11-13, one drop of 2%
cyclosporin in olive oil was administered twice daily.
A significant increase in tearing was observed. On days
4-10, as graphed by the squares, one drop of 2%
cyclosporin in olive oil was administered twice daily.
On days 11-13, one drop of olive oil was applied to each
eye twice daily. The significant increase in tearing
observed over days 4-10 persisted through days 11-13 in
the absence of cyclosporin treatment.
The data conclusively demonstrate that topically
applied cyclosporin increases glandular function, i.e.,
lacrimination, in normal eyes.
Example 7: Topically applied cyclosporin:
Lacrimomimetic effects and reduction of
corneal scars in dogs with ~CS.
Twenty five cases (22 bilateral, 2 unilateral
cases) of spontaneous KCS were treated with a solution
of 2~ cyclosporin (CsA) in olive oil, 1 gtt QD - BID,
OU, and evaluated for changes in tear production as
determined by Schirmer tear test (STT) and for changes
in the surface of the globe.
The effects of cyclosporin were twofold:
cyclosporin increased tear production in 84% of
idiopathic cases of canine KCS and cyclosporin caused
marked regression of corneal pathology including
superficial granulation tissue, neovascularization and
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pigmentation, without retarding healing of corneal
ulcers. Case histories are summarized in Table 1.
The diagnosis of KCS preceded CsA use by 0-60
months, with an average of 1.1 yr. Prior treatment
included artificial tears in 16/25 dogs, oral or topical
pilocarpine in 11/25 dogs, oral or topical
corticosteroids in 11/25 dogs, topical antibiotics in
9/25 dogs, or no prior treatment in 5/25 dogs.
Contrary to expectation, the longevity of KCS did
not correlate inversely with response to therapy. The
average STT before administration of cyclosporin was
2.54 mm/min right eye and 2.46 mm/min left eye. During
the period in which cyclosporin eyedrops were
administered, the mean STT value was 11.38 mm/min right
eye and 11.50 mm/min left eye. The average increase in
STT was 8.84 mm/min right eye (t = 7.5 Student's T -test
for related measures, p<0.0005), and 9.04 mm/min left
eye (t = 6.7, p<0.0005). 38 eyes were initially
diagnosed as having severe KCS (STT 0-4 mm/min).
Following treatment, STT values increased by greater
than 5 mm/min in 84% of severely affected eyes. Dogs
were noted to have increased STT beginning 3 to 56 days
after onset of cyclosporin therapy. Of the six eyes
(6/38, 16%) determined to be nonresponsive, five were
evaluated for only a short period (7 to 35 days).
Because STT value in responsive eyes increased with
increased frequency and duration of treatment (see Table
I, cases 21 and 22), the 84% success rate may be an
underestimate.
In six dogs whose STT values increased in response
to cyclosporin, treatment was discontinued and the STT
values regressed. When cyclosporin was reinstituted,
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the STT increased back to maximal levels in six hours
in one case, and in 1-7 days in the other four cases.
In two dogs receiving cyclosporin on alternate days, the
STT values decreased on nontreatment days. Even with
sporadic interruptions in administration of cyclosporin
treatment, no dog has lost responsiveness to
cyclosporin. Many of the cyclosporin responsive dogs
previously had been unresponsive to corticosteroids
administered topically, subconjunctivally, and
parenterally.
In dogs with superficial corneal granulation
tissue, continuous use of cyclosporin resulted in a
progressive decrease in the abnormal thickness and
opacity of the cornea. Even in dogs that did not have
an increase in tear secretion, alleviation of the
corneal disease was generally marked. Most dogs with
dense blinding pigmentation and superficial granulation
had marked clearing of the corneas after several months
of treatment. Three dogs had corneal ulcers at the
onset of treatment with cyclosporin; each healed within
48 hours of onset of treatment. Dogs maintained for
prolonged periods (8-12 months) relapsed into KCS within
2-3 days of withdrawal of cyclosporin.
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TABLE 1. Previous ocular therapy, and
Schirmer tear test (STT) values
before and while using,
cyclosporin eyedrops in 25 cases
of canine keratoconjunctivitis
sicca.
STT Values
Case #, Breed, Sex, Treatment Before With
Age +/-Keratitis Interval/ CsA CsA
(response to CsA) Frequency OD/OS OO/OS
1. Standard Poodle, F,7 yr 6 wk/QD 3/3 22/16
no keratitis
2. Cocker Spaniel, F 5 mo/BID 0/010/13
7 yr, Pigmentary keratitis
(marked improvement)
3. Min. Schnauzer, F/S, 5 wk/QD 2/0 8/1
11 yr, Pigmentary keratitis
(Marked improvement)
4. Eng. Bulldog, M, 7yr, 7 wk/BID 2/313/20
Chronic keratitis, visual
deficits (Resolved)
5. Samoyed, F/S, 14 yr, 1 mo/BID 2/1118/17
mild keratitis (Resolved)
6. Shih-tzu, M, 10 yr 13 wk/QD 4/1013/14
Pigmentary keratitis, visual
deficits (Marked improvement)
7. Min. Poodle, M, 7 yr, 16 wk/BID 0/011/17
blind dt corneal scarring
(Resolved completely)
8. Mixed breed, F/S, 5 yrs 8 mo/BID 0/0 19/17
diffuse fluorescein uptake
(No staining)
9. W H W Terrier, F/S 5 yr, 4 wks/QD 0/0 13/0
Pigmentary keratitis/blind
(Improved visual)
10. Shih tzu M 4 yr, Chronic 26 wk/QD 15/1 15/6
keratitis OD (Much improved)
1 335566
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Table 1 continued (page 2)
11. Poodle x, F, 6 yr, 22 wk/QD 0/0 12/18
Mild superficial keratitis
(Improved)
12. Shih tzu, F, 3 yr, 17 wk/QD 0/0 3/10
Pigmentary keratitis
(Marked Improvement)
13. Dachshund F, 10 yr, 15 wk/BID 5/0 10/2
Minimal superficial
keratitis (Resolved)
14. Scottish Terrier, M, 9 wk/QD 6/8 12/18
12 yr, Pigmentary keratitis
(50% resolution)
15. Lhasa Apso M/C, 10 yr 8 wk/QD 13/1 18/19
Pigmentary keratitis
(50% resolution)
16. Lhasa Apso M, 9 yr, 5 wk/QD 8/16 19/22
Pigmentary keratitis
(Slight Improvement)
17. Min. Schnauzer, M, 11 yr 9 wk/BID 0/4 5/10
Pigmentary keratitis/
blind (Slight improvement)
18. Min. Poodle F, 7 yr 5 wk/QD / 2/1
Marked keratitis
(Marked improvement)
19. Cocker Spaniel, F, yr 5 wk/QD 7/5 15/10
1.5 yr, no keratitis
20. Boston terrier, F/S, 6 wk/QD 4/4 14/19
7 yr, no keratitis
21. Dachshund, M, 3 yr, 4 wk/BID 1/5 3/17
Mild superficial keratitis
(Nearly resolved)
1 335566
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Table 1 continued (page 3)
22. Peke/Pomeranian X, F/S 12 wk/BID 0/0 20/18
5 yr,Pigmentary keratitis
100% (50% improved)
23. Min. Poodle, M, 9 mo. 4 wk/QD 4/4 13/13
Chronic keratitis
(Marked improvement)
24. Toy Poodle, F/S, 15 yr 7 wk/BID 3/0 16/0
Chronic keratitis, visual
loss (Marked improvement)
25. Peke/Pomeranian, F/S, 11 wk/BID 0/0 8/8
6 yr, Pigmentary keratitis,
blind (Marked improvement/
visual)
Abbreviations: F (female), M (male), C (castrated),
S (spayed), CsA (2% cyclosporin),
QD (once daily), BID (twice daily)
Corneal lesions and changes in the corneal lesions were
bilateral unless otherwise indicated.
-30- 1 3 3 5 5 6 6
FxAmple 8: Stimulation of tearing in hum~ns suffering
from Sjogren's syndrome.
Sjogren's syndrome is characterized by chronic
infiltration of the exocrine glands, principally the
lacrimal and salivary glands, by mononuclear leukocytes.
The process causes the progressive destruction of the
glandular tissue and is characterized by the development
of keratoconjunctivitis sicca (KCS), or ~dry eyen.
Neither topical nor parenteral treatment using steroids
has been completely effective in decreasing irritation
of the corneal surface nor in preventing corneal ulcer
formation. In fact, topical or parenteral
corticosteroids do not enhance lacrimation and can
retard healing of corneal ulcers and are therefore
considered to be contraindicated by many
ophthalmologists.
A human patient with primary Sjogren's syndrome
(dry eye with dry mouth) was treated with topical 2%
cyclosporin in corn oil. The patient had been treated
for years with conventional therapy, artificial tears
Q 15 mins. For the past several months his STT were 2-
3 mm/5min/eye. (In humans the STT is measured for 5
minutes, unlike the dog where it is measured for only
1 min. However, the expected normal values are the
same, i.e., normal is 14 mm, values under 5 mm are
indicative of a severe case of dry eye).
Following 9 days of twice daily therapy of both
eyes, his STT was 20 and 23 mm/5 min/eye, a significant
increase over the pretreatment values. Prior to
treatment, the corneas had stained diffusely in both
eyes with fluorescein dye, an indication of corneal
ulcers. After 9 days of therapy, one eye had no
1 335566
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staining and one eye only stained over 1/3 of the
surface.
Three women with severe chronic secondary
Sjogren's syndrome were treated for 1 week with BID 2%
cyclosporin in corn oil containing 1 mole% alpha
tocopherol and 0.005%methyl paraben. All three had
abnormal corneas. The first had a nonhealing corneal
ulcer which penetrated the full thickness of the surface
epithelium covering the cornea. This ulcer healed
within two days of onset of therapy. The second had a
"contact lens cornean, an indentation at the
circumference of the cornea which gives it the
appearance of an eye wearing a contact lens, when no
lens is present, which is analogous to a scar. The
indentation showed evidence of filling in within 7 days
of therapy. The third had corneal lesions which also
showed improvement within one week. All had increases
in the STT.
The results conclusively demonstrate the
effectiveness of topically administered cyclosporin in
alleviating the symptoms of KCS, promoting normal
healing and actually reducing scar tissue on the surface
of the eye.
Example 9: Promotion of normal healing of the eye
surface without restor~tion of normal te~ring
in a dog.
An ll-year old spayed Miniature Schnauzer had been
determined to have KCS 8 months before admission.
Analysis of a specimen obtained by conjunctival scraping
at that time revealed distemper virus. The dog had been
treated with 2% pilocarpine, (1 gtt P0 q 12 h) which
initially caused an increase in the STT to 8 mm/min
1 335566
bilaterally but later lost efficacy, as the STT
decreased to 0 mm/min bilaterally. Treatment had been
dexamethasone ointment Q 12 h bilaterally, artificial
tears approximately 6 times daily, and petrolatum
ointment at bedtime. On admission, ophthalmic
observation showed the STT to be 2 mm/min right eye, 0
mm/min left eye, with mucoid conjunctivitis bilaterally,
dorsal corneal pigmentation of approximately 40-50% of
the corneal surface, and superficial neovascularization
extending approximately 6 mm into the dorsal half of the
cornea bilaterally (Fig. 2B). The corneal surfaces were
modeled irregularly but translucent, and there were no
apparent visual deficits. Complete blood count and
serum thyroxin were normal and the only abnormality
detected on serum profile was an elevated serum alkaline
phosphatase (667 mg/dl).
Cyclosporin (2% 1 gtt QD, bilaterally) was
prescribed, with artificial tears to be administered as
needed. In 4 weeks, the STT had increased to 8 mm/min
in the right eye but was still 0-1 mm/min in the left
eye. The conjunctivitis had improved, but was still
evident in the left eye. However, there was marked
improvement of the corneal surface bilaterally (Fig.
2B).
A parotid duct transposition was performed at this
time and the lacrimal gland of each third eyelid
biopsied. Microscopically both glands were similar,
with diffuse often intense periductal and interstitial
infiltration of plasma cells and lymphocytes, and
fibrosis of the acini and tubules. Focal areas of normal
acinar tissue were seen in each gland, and some areas
contained dilated tubules lined with flattened
1 335566
epithelium. The results in the preceding examples
establish that topically applied cyclosporin can be used
to resolve corneal ulcers even in the absence of
restoration of tearing. As dramatically shown by Figure
2A and 2B, the eye surface becomes clearer, smoother,
and vision is improved.
Ex~mple 10: Comparison of olive oil and corn oil
vehicles for cyclosporin for topical
ophthalmic use.
Among the animals treated with cyclosporin in
olive oil, within four days of beginning treatment, four
dogs and one cat had ocular irritation reactions
including: -hyperemia of the bulbar conjunctiva, corneal
surface irregularities with apparent corneal edema, and
blepharospasms indicative of ocular pain.
In each case therapy was withdrawn and these
symptoms resolved. Therapy with cyclosporin in corn
oil was begun in three of the dogs following resolution
of the ocular irritation reactions. All three dogs
tolerated the corn oil/cyclosporin mixture well.
In the fourth dog, cyclosporin in olive oil was
used less frequently than the BID prescription because
the owner thought the drug irritated the eyes, but kept
using it on an infrequent basis. Following two to three
weeks of use, bilateral periocular alopecia occurred and
the lids were intensely hyperemic. The cyclosporin in
olive oil was discontinued for several weeks.
Cyclosporin in corn oil was begun BID bilaterally. The
lesions of chronic corneal vascularization and
superficial keratitis resolved markedly, the STT
increased, and there was no recurrence or irritation or
alopecia.
1 335566
-34-
Olive oil and corn oil were also compared in
normal, human eyes. The olive oil produced a burning
sensation lasting 15 to 60 minutes. The corn oil
produced a milder sensation lasting only 1 to 2 minutes.
No side effects have been noted in the any of the
3000 bottles of 2% cyclosporin in corn oil dispensed for
animal use, in comparison with the 5 to 10% incidence
of side effects in 1000 bottles of 2% cyclosporin in
olive oil dispensed for animal use. The substantial
difference in tolerance of the two oils is surprising
since the chemical nature of olive oil and corn oil is
very similar. Tests of the levels of free fatty acids
and pH do not indicate any significant differences which
could account for the decreased tolerance for olive oil.
Substitution of purified olive oil, Sigma Chemical Co.,
St. Louis, M0, or first press olive oil, for the Berio
brand olive oil, obtained from the grocery store, which
was used initially, does not eliminate the irritation.
Modifications and variations of the present
invention, an improved cyclosporin composition for
topical ophthalmic use, will be obvious to those skilled
in the art from the foregoing detailed description of
the invention. Such modifications and variations are
intended to come within the scope of the appended
2S claims.
I claim:
