Nitric oxide releasing prostaglandin derivatives for treating normal tension glaucoma

1. A method of lowering intraocular pressure in a patient with normal tension glaucoma, comprising administering to the patient a compound of formula (I), or a pharmaceutically acceptable salt or stereoisomer thereof

R—X—Y—ONO 2

(I)

wherein R is the prostaglandin residue of formula (II):

wherein

X is —O—;

Y is a bivalent radical having the following meaning:

straight or branched C 1 -C 10 alkylene.

2. The method of claim 1 , wherein the compound of formula (I) is selected from the group consisting of:

3. The method of claim 1 , wherein the compound of formula (I) is compound (1).

4. The method of claim 1 , wherein the compound of formula (I) is administered as ophthalmic pharmaceutical formulation comprising ophthalmically acceptable excipients.

5. The method of claim 1 , wherein the compound of formula (I) is administered with a further active principle selected from the group consisting of a beta-blocker, a carbonic anhydrase inhibitor and an adrenergic agonist.

6. The method of claim 3 , wherein compound (1) is administered with a further active principle selected from the group consisting of a beta-blocker, a carbonic anhydrase inhibitor and an adrenergic agonist.

7. The method of claim 5 , wherein the compound of formula (I) and the further active principle are administered as ophthalmic pharmaceutical formulation comprising ophthalmically acceptable excipients.