Istalol? is our once-daily, topical ophthalmic solution of timolol, a beta-blocking agent for the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.
Glaucoma is a chronic disease that gradually reduces eyesight without warning and often without symptoms. If undetected and untreated, glaucoma can lead to irreversible eye damage and eventual blindness. According to the Glaucoma Research Foundation, in the United States glaucoma is the cause of an estimated 9-12% of all blindness cases and is the second leading cause of blindness. Currently, its causes are not well understood and there is no cure.
How Istalol? Works (Mechanism of Action):
The most common form of glaucoma is known as Primary Open Angle Glaucoma (POAG). This condition is typically seen with increasing frequency with advancing age and approximately three million Americans have POAG. There are many unknown factors in the onset and progression of the condition. Currently, it is thought of as an optic neuropathy that leads to a characteristic pattern of loss of vision. It is evident that intraocular pressure is a risk factor and that, in general, lowering intraocular pressure prevents or stabilizes vision loss. It is also clear that characteristic vision loss can occur in eyes that have low intraocular pressures, and further, that these eyes often benefit from further lowering of intraocular pressure.
The precise cellular and biochemical abnormalities in POAG are not fully delineated. A number of pharmacological approaches and drug classes have been introduced to lower intraocular pressure. Mechanistically, the situation in glaucoma can be separated into two factors: a) the fluid made inside the eye is over-produced, or b) the anatomical arrangement for the transport of the fluid from inside to outside the eye is relatively blocked and acts like a dam that prevents egress of the fluid. The two factors could also occur at the same time.
Istalol? is a non-selective ?-blocker that is applied to the surface of the eye once a day. It significantly reduces the amount of fluid (aqueous) that is produced by the ciliary body. The exact mechanism for the decreased production of aqueous within the ciliary body is not completely elucidated. It is a solution (not a suspension or gel) with excellent drug penetration based upon a modification in its formulation. The unique feature of Istalol? as compared to other topical ophthalmic ?-blockers is the once daily application without resorting to uncomfortable gel or suspension formulations.
