Topical ophthalmological atropine free base compositions

Abstract

A topical ophthalmological composition includes a muscarinic receptor antagonist as an active pharmaceutical ingredient; and a semifluorinated alkane, as a liquid vehicle. The topical ophthalmological composition treats an ocular disease.

Claims

1. A topical ophthalmological composition comprising: atropine as an active pharmaceutical ingredient; and a semifluorinated alkane, as a liquid vehicle, wherein the topical ophthalmological composition treats myopia for those in need thereof, wherein the atropine is in a free base form, and wherein a concentration of the atropine in a free base form is from about 0.0083% to about 0.0129% (w/w).

2. The topical ophthalmological composition of claim 1, wherein the semifluorinated alkane is a compound of formula RFRH or of formula RFRHRF, wherein RF is a perfluorinated hydrocarbon with 15 or less carbon atoms, and wherein RH is a non-fluorinated hydrocarbon with 15 or less carbon atoms.

3. The topical ophthalmological composition of claim 2, wherein the semifluorinated alkane is selected from the group consisting of F4H5, F4H6, F6H4, F6H6, F6H8 and F6H10.

4. The topical ophthalmological composition of claim 3, wherein the semifluorinated alkane is F6H8 (perfluorohexyloctane).

5. The topical ophthalmological composition of claim 1, further comprising an organic cosolvent selected from the group consisting of phenylethyl alcohol, ethanol, isopropanol, glycerol, propylene glycol, and polyethylene glycol.

6. The topical ophthalmological composition of claim 5, wherein the organic cosolvent is ethanol or phenylethyl alcohol.

7. The topical ophthalmological composition of claim 6, wherein the concentration of ethanol is about 1% (w/w) or less; or the concentration of phenylethyl alcohol is about 1% (w/w) or less.

8. The topical ophthalmological composition of claim 1, wherein the topical ophthalmological composition is a non-aqueous solution, a suspension, or an emulsion.

9. The topical ophthalmological composition of claim 8, wherein the atropine in the topical ophthalmological composition is chemically stable for at least 0.5 year, for at least 1 year, or for at least 2 years.

10. The topical ophthalmological composition of claim 1, wherein the topical ophthalmological composition is adapted for topically administering as eye drops to an eye of a patient.

11. The topical ophthalmological composition of claim 10, wherein the topical ophthalmological composition causes minimal irritation in the eye.

12. The topical ophthalmological composition of claim 1, wherein the topical ophthalmological the composition slows a myopia progression.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

(2) In the drawings:

(3) FIG. 1 shows the chromatogram of Atropine (tR: 12.947) standard solution.

(4) FIG. 2 shows pupil dilation effect in rabbit: CBT-009=atropine F6H8 formulation; Comparator=atropine water formulation.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

(5) Reference will now be made in detail to embodiments of the present invention, example of which is illustrated in the accompanying drawings.

(6) A muscarinic receptor antagonist is an anticholinergic agent that blocks the activities of a muscarinic acetylcholine receptor. The muscarinic receptor antagonist may be atropine, pirenzepine, aclidinium bromide, benztropine, cyclopentolate, diphenhydramine, doxylamine, dimenhydrinate, dicyclomine, darifenacin, flavoxate, hydroxyzine, ipratropium, mebeverine, oxybutynin, procyclidine, scopolamine, solifenacin, tropicamide, tiotropium, trihexyphenidyl, or tolterodine. Preferably, the muscarinic receptor antagonist is atropine or pirenzepine. More preferably, the muscarinic receptor antagonist is atropine.

(7) Atropine solution (water) formulations had been previously proven effective in treating myopia, specially reducing myopia progression. The solution formulation had two drawbacks. The first is that once the container opens to air, the atropine at neutral pH in the solution is prone to degradation, therefore, the shelf life of the product at neutral pH is often less than 1 year. Furthermore, this instability of the atropine in the solution requires that the formulation is used within about a month. The second shortcoming is that the low pH, such as in the pH range of 3.5 to 6.0, used to reduce atropine degradation to increase product shelf life, can cause irritation or discomfort to the human eye as reported of adverse events in the patients.

(8) This disclosure provides compositions using a semifluorinated alkane, in particular F6H8 (perfluorohexyloctane), as the liquid vehicle to dissolve atropine to eliminate the two shortcomings of the solution formulation. F6H8 is an amphiphilic liquid with two mutually immiscible moieties (hydrocarbon segment as RH and perfluorinated segment as RF) bound covalently. Other related analogies used in the compositions of the present inventions may be F4H5 (perfluorobutylpentane), F4H6 (perfluorobutylhexane), F6H4 (perfluorohexylbutane), F6H6 (perfluorohexylhexane), and F6H10 (perfluorohexyldecane).

(9) The structure of F6H8 is shown below.

(10) ##STR00001##

(11) In some embodiments, the disclosure is based on the studies described in the examples that show atropine can be dissolve in F6H8 at sufficient concentration to have biological efficacy. The formulation of atropine in F6H8 is stable for prolonged times at room temperature and can be made into a product with sufficient self-life for regulatory approval. This formulation is not irritating in the eye in animal model studies when dosed at a concentration higher than what is needed for some indications.

EXAMPLES

Example 1: Dissolution of Atropine in F6H8

(12) Methods: Formulations of atropine free base were investigated according to the following procedure:

(13) 1. Dissolving Atropine

(14) Added more than 4 mg of atropine powder in 4 mL of F6H8 or F6H8 with 0.1% ethanol, yielding about 1 mg/mL. Stirred the formulation for 2 days.

(15) 2. Preparing HPLC Samples

(16) Centrifuged the formulations above and filtered the supernatants through 0.45 micron filters without further dilution. One sample was prepared from each solvent for HPLC analysis.

(17) 3. Analyzing the HPLC Samples

(18) The samples were analyzed using a RP-HPLC method with an Agilent Eclipse Plus C18 HPLC column (150 mm×2.1 mm I.D.) connected with a guard column (12.5 mm×2.1 mm I.D.) and a gradient elution from 100% water to 100% acetonitrile at a flow rate of 0.2 ml/min. The chromatograms were monitored at UV at 220 nm. The atropine peak is at retention time 12.947 as shown in the chromatograph in FIG. 1.

(19) Results

(20) The solubility of atropine was determined to be 129 μg/ml (0.0129% w/w) in F6H8 alone. When 0.1% ethanol was added, the solubility was 171.5 μg/ml (0.0173% w/w). In this particular study, the free base form of atropine was used, while the mono sulfate salt was previously used in the solution formulation approved for myopia usage. The 1\4W of the free base is 83% equivalent to the mono sulfate salt form of atropine solution formulation. The 0.01% atropine mono sulfate salt solution was previously shown effective for myopia treatment in the clinic and was approved in several countries. This 0.01% atropine salt concentration was equivalent to 0.0083% of the free base concentration. Since the maximum atropine free base that we observed in F6H8 was 0.0129%, we concluded that the F6H8 formulation can deliver sufficient amount of atropine for the treatment of myopia. The 0.0129% concentration we observed was about 55% higher than the 0.0083% needed for efficacy. In addition, we observed that the concentration of atropine can be increased further by adding ethanol to the formulation. The addition of just 0.1% ethanol increased the solubility by 33%. Higher levels of ethanol would likely further increase the solubility of atropine in F6H8. The concentrations of atropine in the F6H8 formulations are show in Table 1.

(21) TABLE-US-00001 TABLE 1 Concentrations of Atropine in F6H8 formulations Atropine in F6H8 with Sample Descriptions Atropine in F6H8 0.1% (v/v) Ethanol Solubility (concentrations) 129.0 μg/mL 171.5 μg/mL

Example 2: The Atropine F6H8 Formulation is Stable Over Time

(22) Methods

(23) Atropine is dissolved in F6H8 as described in Example 1. The level of atropine is measure by the HPLC method at 25° C. at 1, 3, 6, 9 and 12 months. The atropine in the formulation is defined as stable if the level is maintained between 90-110% of the original level.

(24) Results

(25) During the study period, atropine is stable as shown in Table 2 below.

(26) TABLE-US-00002 TABLE 2 Atropine stability in F6H8 formulation Time point (month) 1 3 6 9 12 Remaining 90-110% of time zero yes yes yes yes yes (yes/no)

Example 3: The Atropine F6H8 Formulation is Tolerable in a Rabbit Study

(27) Methods

(28) The atropine F6H8 formulation is evaluated in rabbits for ocular tolerability. The study design and assessments are shown in Tables 3 and 4.

(29) TABLE-US-00003 TABLE 3 Experiment Design Number of Group Animals & Sex Right Eye Left Eye Dose Frequency 3 3F Vehicle 0.01% atropine Four Times per day, 4 hrs apart

(30) TABLE-US-00004 TABLE 4 Study Assessments Parameters Descriptions Viability Twice daily Clinical Observation Once during the predose and once daily during the dosing phase after the last daily dose. Body weight Once during the predose, and on Day 1, Day 7 and Day 14 Food consumption Once daily during predose and dosing phase Ocular Discomfort Twice (on different days) during the observation predose phase, daily during the dosing phase after the last daily dose. Both eyes will be grossly examined and graded using a modified Hackett-McDonald grading scale by technical staff Ocular Irritation Twice (on different days) during the Observation (Modified predose phase, daily during the dosing Hackette McDonald) phase after the third daily dose. Both eyes will be grossly examined and graded using a modified Hackett-McDonald grading scale by technical staff Cornea Examination Once predose phase and once after the last daily dose on Day 1 and Day 14. Both eyes will be examined for corneal opacity and % of corneal opacity using slit lamp and will be taken photos.

(31) Results and Conclusions

(32) The atropine formulation is well tolerated in rabbits with no significant irritation and discomfort issues.

Example 4: Stability of Atropine in F6H8

(33) 0.01% atropine was dissolved in F6H8 and 0.25% phenylethyl alcohol. The stability of the atropine formulation over time was accessed at 25° C. and 40° C. At selected time points, atropine was extracted with acetonitrile twice and quantitated by HPLC as describe in Example 1. Table 5 below shows that atropine levels remained stable at Days 32 and 84 without significant change from the baseline at Day 0. The results were similar at both room temperature and accelerated temperature. The stability at accelerated temperature indicated that the formulation can be potentially stored at room temperature for months or years without significant loss of atropine. This example, disclosed for the first time, demonstrated that the atropine formulation in the invention was stable for prolonged storage at room temperature.

(34) TABLE-US-00005 TABLE 5 Stability of atropine in F6H8 and 0.25% phenylethyl alcohol 25° C. 40° C. Concentration Concentration Time (days) (μg/mL) % of time 0 (μg/mL) % of time 0 0 99.2 99.2 32 94.0 94.8% 94.5 95.3% 84 110.8 111.7% 114.3 115.2%

Example 5: In Vivo Ocular Tolerability in Rabbits

(35) Study Design:

(36) Three (3) female Dutch belted rabbits were given 40 μL of Control Article (0.01% atropine sulfate monohydrate in normal saline) to the right eyes and 40 μL of 0.012% atropine free base in 0.25% phenylethyl alcohol (PEA) in F6H8 to the left eyes, 1 drop/eye, twice per day, 12 hrs apart for 14 consecutive days. Ocular discomfort observation and ocular irritation observation were performed for all animals at predose (twice, on different days) and daily during the dosing phase after the last daily dose. Cornea examination were performed for all animals at predose (once) phase and once after the last daily dose on Day 1 and Day 14. The first dosing day were designated as Day 1.

(37) The ocular irritation scores on Day 14 were shown Table 6 below. Other time points had similar or better results.

(38) TABLE-US-00006 TABLE 6 Day 14 Cornea Opacity Opacity Conjunctiva Animal intensity area Iris Congestion Swelling Discharge ID Subject OD OS OD OS OD OS OD OS OD OS OD OS C0866 1501 0 0 0 0 0 0 0 0 1 1 0 0 C0863 1502 0 0 0 0 0 0 0 0 1 1 0 0 C0867 1503 0 0 0 0 0 0 0 0 1 1 0 0

(39) McDonald-Shadduck scoring (categories with positive scores) was shown in Table 7 below.

(40) TABLE-US-00007 TABLE 7 Cornea Conjuctiva Aqueous Cloudiness Animal Congestion Discharge Flare Iris Cloudiness Area Pannus Fluorescein ID Subject OD OS OD OS OD OS OD OS OD OS OD OS OD OS OD OS OD OS Day 1 C0866 1501 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 0 C0863 1502 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 C0867 1503 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Day 14 C0866 1501 0 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 C0863 1502 0 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 1 C0867 1503 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 1 0

(41) Conclusion: The atropine formulation was well tolerated in all animals. No significant ocular irritation or ophthalmic findings were observed in any animals. There were no test article-related effects on body weights and food consumption during the studies in both species. There were no other test article-related ophthalmologic findings during the scheduled examinations for all animals. This Example demonstrated the safety of the claimed novel formulation of atropine for ocular use.

Example 6: In Vivo Ocular Tolerability in Dogs

(42) Study Design

(43) Three (3) male Beagle dogs were given 40 μL of Control Article (0.01% atropine sulfate monohydrate in normal saline) to the right eyes and 40 μL of 0.012% atropine free base in 0.25% phenylethyl alcohol (PEA) in F6H8 to the left eyes, 1 drop/eye, twice per day, 12 hrs apart for 14 consecutive days. Ocular discomfort observation and ocular irritation observation were performed for all animals at predose (twice, on different days) and daily during the dosing phase after the last daily dose. Cornea examination were performed for all animals at predose (once) phase and once after the last daily dose on Day 1 and Day 14. The first dosing day was designated as Day 1.

(44) The ocular irritation scores on Day 14 were shown in Table 8 below. Other time points had similar or better results.

(45) TABLE-US-00008 TABLE 8 Day 14 Cornea Opacity Opacity Conjunctiva Animal intensity area Iris Congestion Swelling Discharge ID Subject OD OS OD OS OD OS OD OS OD OS OD OS 8525538 1001 0 0 0 0 0 0 1 1 0 0 0 0 8370950 1002 0 0 0 0 0 0 0 0 0 0 0 0 8473172 1003 0 0 0 0 0 0 1 1 0 0 0 0

(46) McDonald-Shadduck scoring (categories with positive scores) was shown in Table 9 below.

(47) TABLE-US-00009 TABLE 9 Cornea Conjuctiva Aqueous Cloudiness Animal Congestion Discharge Flare Iris Cloudiness Area Pannus Fluorescein ID Subject OD OS OD OS OD OS OD OS OD OS OD OS OD OS OD OS OD OS Day 1 8525538 1001 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 8370950 1002 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 8473172 1003 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Day 14 8525538 1001 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8370950 1002 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8473172 1003 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

(48) Conclusion: The atropine formulation was well tolerated in all animals. No significant ocular irritation or ophthalmic findings were observed in any animals. There were no test article-related effects on body weights and food consumption during the studies in both species. There were no other test article-related ophthalmologic findings during the scheduled examinations for all animals. This Example demonstrated the safety of the claimed novel formulation of atropine for ocular use.

Example 7: In Vivo Pharmacological Potency in a Rabbit Model

(49) The pharmacological potency of the atropine formulation in F6H8 and 0.25% phenylethyl alcohol was tested in a rabbit model. The potency was measured as pupil dilation in normal naïve rabbits. Three concentrations of the F6H8 formulation of atropine (0.012%, 0.01%, 0.08%) were compared to that of an aqueous formulation of 0.01% atropine which was known to have good pupil dilation effects. One drop of each formulation was dosed into the eye and pupil size was measured during the following 8 hours.

(50) Study Design

(51) Fifteen (15) female Dutch belted rabbits were assigned to five groups, which included 3 animals/group. Three (3) female Dutch belted rabbits were randomly assigned to each group by Provantis or Excel based on body weight. The dosing of animals was performed in 2 phases, Phase 1 and Phase 2.

(52) In phase 1, each animal was given 40 μL of testing article (see Table 10 below) to both eyes. First day of dosing was designated as Day 1. The pupil size of both eyes of all animals were measured at baseline (30 minutes before dosing), 0.5 h, 1 h, 2 h, 3 h, 4 h, 6 h, 8 h after dosing on day 1. The pupil size measurement data were analyzed for efficacy to determine which doses of atropine free base in Vehicle was equivalent to the dose of the control group of 0.01% atropine sulfate monohydrate in normal saline. Animals were allowed 2 days for wash-out period.

(53) In phase 2, each animal was given 40 μL of testing article (see Table 11 below) to both eyes for 14 days. First day of dosing in Phase 2 was designated as Day 4. The pupil size of both eyes of all animals were measured at baseline (30 minutes before dosing), 0.5 h, 1 h, 2 h, 3 h, 4 h, 6 h, 8 h after dosing on Day 4 and Day 17.

(54) TABLE-US-00010 TABLE 10 The study design of phase 1 Group/ Animal Code Treatment Number Dosage & Color Animals.sup.a Both eyes Female Frequency 1/White 3 0.01% atropine 1501-1503 Once a day, 1 sulfate drop/eye, on monohydrate Day 1 followed in normal saline by 2 days 2/Green 3 0.012% atropine 2501-2503 wash-out free base in Vehicle period 3/Yellow 3 0.008% atropine 3501-3503 free base in Vehicle 4/Red 3 0.005% atropine 4501-4503 free base in Vehicle 5/Cyan 3 Vehicle 5501-5503 Note: .sup.aReplacement animals, if any, will be numbered per Testing Facility SOP and will be included in the study report. Vehicle: 0.25% phenylethyl alcohol in 1-(perfluorohexyl)octane

(55) TABLE-US-00011 TABLE 11 The study design of phase 2 Group/ Animal Code Treatment Number Dosage & Color Animals.sup.a Both eyes Female Frequency 1/White 3 0.01% atropine 1501-1503 Once a day, 1 sulfate monohydrate drop/eye, on in normal saline Day 4 to Day 2/Green 3 Dose to be 2501-2503 17. Pupil size determined after will be Day 1.sup.b measured on 3/Yellow 3 Dose to be 3501-3503 Day 4 and determined after Day 17 only. Day 1.sup.b 4/Red 3 Dose to be 4501-4503 determined after Day 1.sup.b 5/Cyan 3 Vehicle 5501-5503 Note: .sup.aReplacement animals, if any, will be numbered per Testing Facility SOP and will be included in the study report. .sup.bEquivalent dose is determined from Phase 1 efficacy data. The optimized concentrations of atropine free base in Vehicle that gives equivalent efficacy as 0.01% atropine sulfate monohydrate in normal saline. Vehicle: 0.25% phenylethyl alcohol in 1-(perfluorohexyl)octane

(56) Results

(57) As shown in FIG. 2, the F6H8 formulation of atropine increased pupil size with similar potency to that of the water formulation. The 0.01% F6H8 formulation was slightly more effective than the water formulation. This observation indicated that the novel F6H8 of atropine was as effective as a proven atropine formulation and can be used for the treatment of diseases with water-based formulations. FIG. 2 showed pupil dilation effect in rabbit: CBT-009=atropine F6H8 formulation; Comparator=atropine water formulation.

(58) It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

REFERENCES

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