An inexpensive cancer drug improves vision in people with a debilitating form of sight loss known as wet age-related macular degeneration, researchers reported today in BMJ.

The drug, sold under the brand name Avastin, is not approved to treat vision loss, but is still widely used off-label as a cheap alternative to the drug Lucentis, both of which are sold by Genentech. The findings will likely fuel the debate over which drug to prescribe for a wide range of vision loss disorders.

Researchers from three British eye hospitals treated more than 130 people with macular degeneration with either Avastin injections or one of three forms of standard care currently offered by the UK National Health Service, Britian’s public healthcare provide. After one year, they found that around one-third of the Avastin patients gained three lines of vision on a standard eye chart, compared to only around 3% of the standard care group.

Earlier this month, we reported how researchers from one of these hospitals also showed that Avastin — a monoclonal antibody that is only approved for some forms of cancer — was more effective than standard laser treatment for treating a similar disease known as diabetic macular edema. Together, the studies lend weight to calls for regulators to approve Avastin for these eye conditions as a low-cost substitute for Lucentis, which is its truncated form.

In an accompanying commentary, however, Usha Chakravarthy, an opthamologist at the Royal Victoria Hospital in Belfast, UK, notes that the study does not answer the question of whether Avastin is equally or more effective than Lucentis. As such, she advises physicians not to rush off to prescribe Avastin until the results of two large trials testing the drugs head-to-head for macular degeneration are announced.

Image: NIH