Eye drops for treatment of irritation not due to infection

Abstract

A method for treatment of irritation or damage to corneal or conjunctival epithelial cells, particularly for irritation or damage to corneal or conjunctival epithelial cells due to severe Sjögren's syndrome, comprising applying topically to an affected eye an aqueous solution of glycerol characterized by a glycerol concentration of >1% (w/v), most preferably 2.5% (w/v). The method is effective even in the case of very low tear formation, and its effectiveness cannot be explained by the known humectant effect of glycerol.

Claims

1. A method for treating irritation or damage to conjunctival or corneal epithelial cells resulting from Sjögren's syndrome, said method comprising: characterizing said Sjögren's syndrome by a method selected from the group consisting of: determining a LIPCOF score; and, determining a level of devitalization of said conjunctival or corneal epithelial cells by a method selected from the group consisting of Rose Bengal staining and Lissamine Green staining; further characterizing said Sjögren's syndrome by a value representing a level of tear production as measured by a Schirmer's test; applying at predetermined intervals to an affected eye an ophthalmic preparation comprising an aqueous solution comprising glycerol and a substance selected from the group consisting of hyaluronic acid and hyaluronate; wherein: said step of applying an ophthalmic preparation comprises applying at predetermined intervals said ophthalmic preparation to an affected eye until at least one condition selected from the group consisting of: said LIPCOF score is statistically significantly lowered without any statistically significant change in said value of said Schirmer's test measurement; and, a statistically significant reduction in the level of devitalization of said conjunctival or corneal epithelial cells, as measured by said Lissamine Green or Rose Bengal staining, is observed, without any statistically significant change in said value of said Schirmer's test measurement; is met; and, said ophthalmic preparation is characterized by a glycerol concentration of between 1.1% and 4% (w/v) and a concentration of said substance selected from the group consisting of hyaluronic acid and hyaluronate of 0.015% (w/v).

2. The method according to claim 1, wherein said method is a method for treating irritation or damage to conjunctival or corneal epithelial cells resulting from severe Sjögren's syndrome.

3. The method according to claim 1, wherein said aqueous solution is essentially isotonic.

4. The method according to claim 1, wherein said aqueous solution has a pH of between 6.7 and 7.7.

5. The method according to claim 1, wherein said aqueous solution has an inorganic salt concentration of less than 0.1% w/v.

6. The method according to claim 1, wherein said aqueous solution is selected from the group consisting of: an aqueous solution comprising between 1.1% and 4% (w/v) glycerol and 0.015% (w/v) hyaluronate, said hyaluronate characterized by a molecular weight of at least 10,000 Dalton; an aqueous solution comprising between 1.1% and 4% (w/v) glycerol, 0.015% (w/v) hyaluronate, and a polymer characterized by a molecular weight of at least 10,000 Dalton; and, an aqueous solution comprising between 1.1% and 4% (w/v) glycerol, 0.015% (w/v) hyaluronate, and a polymer, said hyaluronate and said polymer both characterized by a molecular weight of at least 10,000 Dalton.

7. The method according to claim 6, wherein the concentration of said polymer is chosen to bring said aqueous solution to a viscosity of between 5 and 125 mPa.Math.s.

8. The method according to claim 6, wherein said polymer is a carbomer.

9. The method according to claim 1, wherein said aqueous solution comprises a pharmaceutically effective amount of a pharmacologically active agent.

10. The method according to claim 1, wherein said aqueous solution further comprises stabilizers, preservatives, antioxidants, or buffers.

11. The method according to claim 1, wherein said ophthalmic preparation consists of an aqueous solution consisting of 2.5% glycerol (w/v), 0.015% sodium hyaluronate (w/v), 0.015% carbomer 981 (w/v), a sufficient amount of acid or base to adjust said solution to a pH of between 6.7 and 7.7, and the balance water.

12. The method according to claim 11, wherein said ophthalmic preparation consisting of said aqueous solution is applied to said eye affected by said Sjögren's syndrome as characterized by a value of 1.6±0.3 mm for the level of tear production as measured by a one-minute Schirmer's test.

13. The method according to claim 1, wherein said method comprises applying said ophthalmic preparation from three to eight times daily.

14. The method according to claim 13, wherein said method comprises applying said ophthalmic preparation three to eight times daily for a period of time not exceeding three months.

15. The method according to claim 1, wherein said method further comprises applying said ophthalmic preparation prophylactically following completion of a therapeutic course of the treatment of the irritation or damage to the conjunctival or corneal epithelial cells.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(1) In the following description, various aspects of the invention will be described. For the purposes of explanation, specific details are set forth in order to provide a thorough understanding of the invention. It will be apparent to one skilled in the art that there are other embodiments of the invention that differ in details without affecting the essential nature thereof. In some cases, for clarity or conciseness, individual components or method steps of the invention are described separately. Nonetheless, any combination of individual elements or method steps that are disclosed herein that is not self-contradictory is considered by the inventor to be within the scope of the invention.

(2) As used herein, the term “severe Sjögren's Syndrome” refers to Sjögren's Syndrome characterized by a 1-minute Schirmer Test of 2 mm or less (see Bawazeer, A. M.; Hodge, W. G., “One-Minute Schirmer Test with Anesthesia,” Cornea 2003, 22, 285-287, which is hereby incorporated by reference in its entirety).

(3) The inventor has discovered that surprisingly, glycerol is an effective substance for treatment of irritation of corneal epithelial cells, irritation of conjunctival epithelial cells, and hence, damage to conical or conjunctival cells when these conditions are caused by factors other than infection, even in the complete absence of tear formation, such as is found in severe Sjögren's Syndrome. Topical application of glycerol (e.g. in an aqueous solution) to the affected eye reduces or even eliminates entirely conical or conjunctival irritation without increasing the rate of tear formation.

(4) The invention herein disclosed is an ophthalmic preparation for treatment or prevention of irritation to corneal or conjunctival epithelial cells, in particular, for treatment of irritation to corneal or conjunctival epithelial cells resulting from severe Sjögren's Syndrome, the preparation comprising an aqueous glycerol solution having a concentration of greater than 1% glycerol (w/v). In typical embodiments of the invention, the solution comprises 1.1%-4% glycerol (w/v). In some preferred embodiments of the invention, the solution comprises 2.5% glycerol (w/v). In preferred embodiments of the invention, the solution is isotonic.

(5) In preferred embodiments of the invention, the composition comprises an aqueous glycerol solution in which the concentration of inorganic salts is less than 2 mM. In preferred embodiments of the invention, the viscosity of the solution is controlled by addition of a quantity of high molecular weight polymer (MW>10.sup.4 Dalton) such as hyaluronate, carbomer or a mixture thereof, sufficient to bring the solution to the desired viscosity. All ingredients are of purity sufficient for use in eye drops.

(6) The solutions may then be transferred to a container appropriate for dispensing it as eye drops.

(7) While in some embodiments of the invention, the only active ingredient present in the composition is glycerol, the composition may comprise in addition a pharmaceutically effective concentration at least one pharmacologically active agent. If necessary, any stabilizer, preservative, antioxidant, buffer or combination thereof appropriate for use with the pharmacologically active agent may be added to the solution in any concentration suitable for use in eye drops.

(8) It is within the scope of the invention to disclose the use of the eye drops in the non-surgical treatment of, or prevention of, irritation of and irritation to the conical or conjunctival epithelial tissue, particularly damage due to causes other than infection, and a method of non-surgical treatment or prevention of irritation of and hence, damage to the corneal or conjunctival epithelial tissue, particularly damage due to causes other than infection. Non-limiting examples of conditions that can be treated by the eye drop composition disclosed herein include Sjögren's syndrome, Meibomian oil deficiency, drug or preservative induced irritation, irritation due to mechanical cell damage such as cell damage induced by contact lens wearing, and ocular surface disease.

(9) A typical protocol for use of the eye drops disclosed herein to treat or to alleviate corneal and/or conjunctival epithelial cell damage is to place drops in the affected eye three to eight times daily until the severity of condition is reduced to an acceptable level. In particularly severe cases, more frequent applications may be necessary, and in less severe cases, one or two daily treatments may be sufficient. The progress of the treatment can be measured by the use of techniques such as Lissamine Green staining or Rose Bengal staining to track the condition of the epithelial cells. In some preferred embodiments of the treatment, application of the composition disclosed herein is performed for no more than three months, by which time statistically significant improvement of the condition of the conical or conjunctival epithelial cells is observed. In some preferred embodiments of the treatment, application of the composition disclosed herein is performed for no more than one month, by which time statistically significant improvement of the condition of the corneal or conjunctival epithelial cells is observed.

(10) It is within the scope of the invention to include within the method prophylactic application of the composition disclosed herein in order to prevent recurrence of the condition. After the course of therapeutic treatment, which typically lasts no more than three months, a maintenance regimen comprising prophylactic application of the eye drops is begun. Application of the eye drops one to three times daily is usually sufficient to prevent recurrence of the irritation.

(11) In contrast to methods known in the art, in particular, those that use drugs that affect the immune system, no side effects were observed in any of the treatment protocols in which the invention disclosed herein was tested. In particular, no side effects were observed with long-term use of eye drops containing as much as 2.5% (w/v) glycerol.

(12) The following examples of the preparation and use of the ophthalmological composition herein disclosed are intended to assist a person having ordinary skill in the art to make and use the invention, and are not to be construed as being in any way limiting.

Example 1

Anti-Irritation Eye Drops

(13) A solution was prepared containing:

(14) TABLE-US-00001 Glycerol 2.5 g Carbomer 981 0.05 g Water to 100 ml

(15) The solution was buffered to a pH of 7.2.

Example 2

Anti-Irritation Eye Drops

(16) A solution was prepared containing:

(17) TABLE-US-00002 Glycerol 2.5 g Sodium hyaluronate 0.015 g Carbomer 981 0.015 g Water to 100 ml

(18) The solution was adjusted to a pH of approximately 7.

Example 3

Anti-Glaucoma Eye Drops

(19) A solution was prepared containing:

(20) TABLE-US-00003 Glycerol 2.5 g Latanoprost 5 mg Carbomer 981 0.03 g Water to 100 ml

(21) The solution was adjusted to pH of between 6.8 and 7.6.

(22) A suitable concentration of preservative may optionally be added.

Example 4

(23) A composition was prepared as described in Example 2 above and was tested on 21 patients suffering from severe Sjögren's syndrome. Results of the study are summarized in Table 1; the value in each column is the mean score with the standard error of the mean given in parentheses. Lissamine Green staining evaluated by Oxford Grade is a measure of the severity of dry eye syndrome, while OSDI (Ocular Surface Disease Index) is a measure of patient satisfaction. At the conclusion of the treatment, the patients' eyes were free of measurable damage.

(24) TABLE-US-00004 TABLE 1 Time Oxford Grade OSDI Index Initial 1.86 (0.1)  55.8 (3.2) 1 month.sup.  0.85 (0.21) 37.7 (4.3) 3 months 0.25 (0.13) 32.5 (4.2)

(25) These results are surprising and unexpected, since the Schirmer's test, which measures the level of tear formation was very low at the start of the study (1.6±0.3 mm) and did not change significantly after 3 months of treatment (1.7±0.3 mm). That is, in the patients treated according to the method herein disclosed, using the composition herein disclosed, objective measures of the level of eye irritation symptomatic of Sjögren's Syndrome due to the severely reduced tear production characteristic of the condition showed a significant decrease, even though the very low level of tear production did not increase. This observation cannot be explained by the known physicochemical moisturizing effect of glycerol.

Example 5

(26) An experiment was performed to investigate the effect in vitro of a solution containing glycerol on human corneal epithelial cells, in particular, on the expression of barrier genes Involucrin, Occludin, Filaggrin, and Cadherin-1.

(27) Immortalized human corneal epithelial cells (HCEC cell line) cultured in DMEM/F12 with 5% FBS and 10 ng/ml human epidermal growth factor (Invitrogen—Gibco). The cells were treated for three hours with one of the following three compositions: (a) an aqueous solution of glycerol (0.27% w/v); (b) 20 μg/ml Polyinosinic:polycytidylic acid (p(I:C), an activator of TLR3 to induce inflammation; and (c) a combination of the two previous compositions.

(28) The expression of the barrier genes was determined at the mRNA level by use of quantitative “real-time” PCR (Q-PCR). Q-PCR was performed on an ABI Prism 7000 sequence detection system (Applied Biosystems, Foster City, Calif.) using the 5′ nuclease assay. Total RNA was isolated using TRIzol (Invitrogen) and 3 μg of total RNA were reverse-transcribed into cDNA by using 15 U of AMV reverse transcriptase (Promega, Madison, Wis., USA) and 0.025 μg/μl random primers (Promega). PCR amplification was performed by using the TaqMan primers and probes. As internal controls, transcripts of cyclophilin A (PPIA) were determined.

(29) The pro-inflammatory challenge p(I:C) (20 μg/ml) markedly decreased the expressions of Involucrin, Occludin, Filaggrin, and Cadherin-1. However, of greatest importance, co-incubation of the human corneal epithelial cells with glycerol (0.27%) during the p(I:C)challenge significantly prevented the barrier-impairing actions of the TLR3 agonist.

(30) These results indicate the pro-differentiating, barrier-repairing, anti-inflammatory and protective effects of glycerol on human corneal epithelial cells. Without wishing to be bound by theory, the results of this experiment may help explain the surprising results observed in the treatment protocol described in the previous example.

Example 6

(31) A study was performed in which twelve commercially available artificial tear formulations were applied to the eyes of patients suffering from Sjögren's syndrome according to the package direction. Treatment periods varied from 2 months to over a year. In no case was any improvement in the condition of the eyes observed. The results of the studies are summarized in Table 2. Letters in parentheses indicate treatment of different patients using the same formulation.

(32) TABLE-US-00005 TABLE 2 Compo- sition Active ingredient(s) length of use 1 dextran, hydroxypropylmethylcellulose (a) >1 year (b) 6 months 2 Zinc hyaluronate 3 months 3 polyethylene glycol 400, propylene glycol, (a) 1 month hydroxypropyl-guar (b) 3 months (c) 6 months  3a Similar to 3 (a) 3 months (b) 6 months 4 Tetrahydrozoline HCl (a) 3 months (b) 3 months 5 hypertonic saline solution (a) 2 months (b) 1 month  5a preservative-free version of 5 >1 year 6 Benzalkonium chloride, Alcohol, Glycerin 2 months (<1%), Witch hazel 7 sodium carboxymethylcellulose (a) 2 months (b) 3 months 8 Propylene Glycol 0.6% 3 months 9 Hypromellose 2.5% >1 year 10  50 mg dexapanthenol & polyacrylic polymer 2 months 11  Naphazoline Hydrochloride >1 year 12  Polyvinyl Alcohol >1 year

Example 7

(33) A study was performed comparing the efficacy of the instant invention to that of hyaluronate-containing humectant eye drops known in the prior art. Sixteen patients suffering from severe dry eye due to Sjögren's syndrome were treated for one month with eye drops containing 0.15% hyaluronic acid as the active ingredient, followed by treatment for one month with eye drops prepared according to the formula given in Example 2 above (i.e. containing both hyaluronic acid and 2.5% (w/v) glycerol). The results are summarized in Table 3.

(34) TABLE-US-00006 TABLE 3 enrollment 1 month 2 month enrollment 1 month 2 month Test od os LIPCOF.sup.a 2.75 ± 0.11 2.69 ± 0.12 1.625 ± 0.125  2.81 ± 0.125 2.625 ±0.125  1.625 ± 0.154 Oxford 3.56 ± 0.22 3.19 ± 0.21 1.69 ± 0.12 3.625 ± 0.22  3.31 ± 0.24 1.625 ± 0.125 Schirmer.sup.b 0.50 ± 0.18 0.56 ± 0.16 0.50 ± 0.13 0.56 ± 0.16 0.56 ± 0.18 0.63 ± 0.18 BUT.sup.c 2.98 ± 0.27 4.60 ± 0.29 4.67 ± 0.28 2.92 ± 0.24 4.60 ± 0.27 4.56 ± 0.29 OSDI 63.4 ± 3.2  44.9 ± 4.0  31.6 ± 3.2  .sup.aLid Parallel Conjunctival Folds scale (0 = least severe, 3 = most severe) .sup.b1-minute Schirmer test (mm) .sup.cTear breakup time (s)

(35) As can be seen from the results summarized in the table, eye drops containing hyaluronic acid as the sole active ingredient did not produce any significant change in the objective LIPCOF and Oxford measurements. In contrast, the values of these measurements returned nearly to normal within a month of treatment using the glycerol-containing eye drops of the invention disclosed herein, even though the level of tear production, as measured by the Schirmer test, remained very low. The subjective OSDI parameter was also significantly improved following treatment with the eye drops of the invention disclosed herein.

(36) These results further demonstrate that the effectiveness of eye drops containing 2.5% glycerol as a treatment for severe Sjögren's syndrome cannot be attributed solely to the known humectant effect of glycerol.