Roche's cancer drug Avastin as a cheaper treatment for wet age-related macular degeneration (wAMD), a leading cause of blindness in the elderly, does not appear to increase deaths or serious side effects, an independent study has concluded.

An analysis of nine clinical trials, three of them unpublished, concluded that health insurance policies favoring the much more expensive Lucentis over Avastin were not supported by current evidence, the news agency Reuters said, reporting on the study published Sept. 15 by the nonprofit Cochrane Collaboration.

Avastin is not licensed for wAMD but it works in a similar way to authorized treatments for the condition, including Lucentis, which is marketed by Novartis and Roche, and Eylea, from Bayer and Regeneron Pharmaceuticals.

A number of doctors in the US and Europe already use Avastin in wAMD on an unapproved basis and some pharmacies provide a service of splitting the cancer medicine into smaller doses for eye injections.

French lawmakers voted in July to allow Avastin's use, while Roche and Novartis have faced recent regulatory scrutiny in France and Italy on suspicion of anti-competitive practices. The companies have denied any wrongdoing.

In France, Avastin costs about €30 euros ($38.84) per dose, against the €900 charged for an injection of Lucentis.

A closely watched US government-sponsored study in 2011 concluded that Avastin worked as well as Lucentis in treating vision loss from wAMD but had more adverse side effects.

The Cochrane paper, however, found that the safety of Avastin when used in wAMD appeared to be comparable with that of Lucentis, except for a higher rate of gastrointestinal disorders.

The Cochrane researchers now plan to conduct a larger review to assess additional sources of evidence.