Bayer and partner Regeneron Pharmaceuticals have begun a late-stage trial of a new compound which they hope will prove to be as effective as Genentech's blindness drug Lucentis.

A Phase III study has been initiated of the firms’ vascular endothelial growth factor blocker VEGF Trap-Eye in the neovascular form of age-related macular degeneration, or wet AMD. The trial, called VIEW 1, will involve a 1,200-patient non-inferiority comparison of the compound with Lucentis (ranibizumab) at more than 200 centres in North America.

The study will evaluate the safety and efficacy of the VEGF Trap-Eye at doses of 0.5mg and 2.0mg administered at four-week dosing intervals and 2.0mg at eight weeks compared to 0.5mg of ranibizumab administered every four weeks. Its primary endpoint is the proportion of patients treated with VEGF Trap-Eye who maintain or improve vision at the end of one year, compared to Lucentis.

The late-stage trial comes on the back of an ongoing Phase II trial where patients who were treated with the VEGF Trap-Eye either monthly or quarterly demonstrated a statistically significant reduction in retinal thickness and improvement in visual acuity after 12 weeks, compared to baseline, Bayer and Regeneron said. There were no drug-related serious adverse events reported, and the treatment was generally well-tolerated.

"Age-related macular degeneration continues to be one of the leading causes of blindness in adults, and new therapies are essential to providing optimal patient care," said Jeffrey Heier of Ophthalmic Consultants of Boston and chair of the steering committee for the trial. "The results of early phase studies of VEGF Trap-Eye suggest it has the potential to be a highly efficacious treatment with less frequent administration.”

Bayer, which signed a deal worth up to $320 million with Regeneron to develop VEGF Trap-Eye, and sell it outside North America, will be hoping that analysts are right in predicting that peak sales of the treatment could reach over $400 million. Lucentis, developed along with Novartis (which markets the drug outside the USA) is certainly doing Genentech proud at the moment, bringing in $209 million in the second quarter. It was approved in the USA in July 2006.