Shares of Regeneron Paharmaceuticals, Inc. (Nasdaq: REGN) soared Tusday after initial results of a study involving treatment to prevent a leading cause of age-related acquired blindness showed significant results.

Shares of Regeneron rose $2.18, or 11.4 percent, to $21.33 in afternoon trading on the Nasdaq Stock Market. Share of the company's research partner, Bayer Healthcare AG (NYSE: BAY) were down 0.16 cents, or 0.26 percent, to $61.38 in trading on the New York Stock Exchange.

The firms said in a statement that preliminary results of a Phase 2 study involving its VEGF Trap-Eye treatment reduced retinal thickness in patients with the neovascular form of age-related macular degeneration, or wet AMD, after 12 weeks. Visual acuity also improved.

Vascular endothelial growth factor, or VEGF, is a naturally occurring protein in the body whose normal role is to trigger formation of new blood vessels to support the growth of the body's tissues and organs. It has also been associated with the abnormal growth and fragility of new blood vessels in the eye, which lead to the development of wet AMD, the companies said.

"We are very pleased with the outcome of this interim analysis and the findings support the potential of the VEGF Trap-Eye to improve the lives of patients suffering from wet AMD, which accounts for 90% of AMD related blindness,' said Kemal Malik, M.D., member of the Bayer HealthCare Executive Committee, responsible for Global Development.

The firms plant to begin the third phase of the program in the second half of 2007. Both companies will commercialize VEGF Trap-Eye outside the United States, while Regeneron will maintain exclusive U.S. rights.