Genentech warns on blindness treatment

Genentech Inc. said Friday that it warned doctors that Lucentis, a treatment for the leading cause of blindness among the elderly, may increase risk of stroke.

Patients taking the highest dose of Lucentis to treat macular degeneration had a 1.2% risk of stroke, four times the risk of a lower dose, according to a letter to doctors from Genentech.

Lucentis has been Genentech’s most successful product introduction. The drug, the first of its kind to restore vision, had $217 million in fourth-quarter sales, a 42% jump from the previous quarter. The warning may create an opportunity for a rival drug, Visudyne from QLT Inc. Visudyne sales fell 29% in the fourth quarter.

A 1% stroke rate “does not sound like a big number to us,” and its effect on Lucentis may be minimal, David Dean, an analyst at Sprott Securities Inc. in Toronto, said in a report Friday.

“Lucentis has decimated Visudyne sales in the U.S., and the thought is that if there is new motivation to reduce patient exposure to Lucentis, then possibly Visudyne could be used in combination,” Dean said in an interview.

Lucentis also competes with OSI Pharmaceuticals Inc.’s Macugen. The Melville, N.Y.-based company said it planned to get out of the eye disease business, through out-licensing, partnering or a sale of Macugen. It reported $9 million in third-quarter sales, compared with $153 million for Lucentis during the same period.

Shares of South San Francisco-based Genentech fell 89 cents to $86.57 in regular trading and declined an additional 57 cents after hours.