U.S. Food and Drug Administration (FDA) has approved Zioptan 
 (tafluprost ophthalmic solution) 0.0015%, the first preservative-free 
prostaglandin analog ophthalmic solution. Zioptan (pronounced 
zye-OP-tan) is approved for reducing elevated intraocular pressure (IOP)
 in patients with open-angle glaucoma (OAG) or ocular hypertension. 
Open-angle glaucoma is the most common form of glaucoma, while ocular 
hypertension is a condition characterized by an increase in pressure 
inside the eye.
Ref : http://www.merck.com/newsroom/news-release-archive/prescription-medicine-news/2012_0213.html  
