According to an Allergan conference call, Bimatoprost seems to have failed to show significant results from midstage studies.
http://www.bloomberg.com/news/2013-05-01/allergan-shares-fall-after-ceo-says-drug-trial-will-be-delayed.html
http://www.bloomberg.com/news/2013-05-01/allergan-shares-fall-after-ceo-says-drug-trial-will-be-delayed.html