Inhibition of irritating side effects associated with use of a topical ophthalmic medication
This invention relates to a method of reducing an irritating or adverse side effect associated with the topical use of an active ophthalmic drug comprising incorporating an effective amount of a cyclodextrin or cyclodextrin derivative into a formulation to complex the active drug such that the concentration of the free active drug is reduced below a tolerable threshold, and incorporating an effective amount of a viscosity increasing agent in said formulation such that the bioavailability of said drug is high enough to be therapeutically effective, wherein the cyclodextrin or cyclodextrin derivative is not required to solubilize the active drug. Another aspect of this invention relates to topical ophthalmic formulations comprising an active drug, a cyclodextrin or cyclodextrin derivative, and a viscosity-enhancing agent, in effective amounts as stated above.
1. A topical ophthalmic formulation comprising bimatoprost at a concentration of from 0.003% and 0.1%, an effective amount of a cyclodextrin derivative, and an effective amount of a viscosity increasing agent.
2. The topical ophthalmic formulation of claim 1 which further comprises an effective amount of buffer necessary to maintain the pH at about 7.3, one or more tonicity agents, and a preservative.
3. The topical ophthalmic formulation of claim 2 wherein the buffer comprises borate and the preservative is stabilized oxychloro complexes.
4. The topical ophthalmic formulation of claim 1 wherein the concentration of bimatoprost is between about 0.01% and about 0.05%.
5. The topical ophthalmic formulation of claim 1 wherein the concentration of bimatoprost is about 0.03%.
6. The topical ophthalmic formulation of claim 1 wherein the concentration of free bimatoprost is less than about 0.02%.
7. The topical ophthalmic formulation of claim 1 wherein the cyclodextrin or cyclodextrin derivative is 2-hydroxypropyl β-cyclodextrin, 2-hydroxypropyl γ-cyclodextrin, or γ-cyclodextrin.
8. The topical ophthalmic formulation of claim 1 wherein the concentration of the cyclodextrin or cyclodextrin derivative is between about 0.1% and about 1.1%.
9. The topical ophthalmic formulation of claim 1 wherein the viscosity agent is sodium carboxymethylcellulose or hydroxypropylmethylcellulose.
10. The topical ophthalmic formulation of claim 1 wherein the viscosity agent is sodium carboxymethylcellulose.
11. The topical ophthalmic formulation of claim 10 wherein the concentration of bimatoprost is 0.03%, which further comprises about 0.6% boric acid, about 0.045% sodium borate, about 0.34% sodium chloride, about 0.14% potassium chloride, about 0.006% calcium chloride, about 0.006% magnesium chloride, and about 0.01% Purite®.
12. The topical ophthalmic formulation of claim 1 wherein the free active drug comprises between about 8% and about 90% of the active drug.
13. The topical ophthalmic formulation of claim 1 wherein the free active drug comprises between about 8% and about 75% of the active drug.
14. The topical ophthalmic formulation of claim 1 wherein the free active drug comprises between about 8% and about 25% of the active drug.