Regeneron Pharmaceuticals' top-selling eye drug, Eylea, bested Roche's Lucentis and Avastin in a U.S.-sponsored study in diabetes-related vision loss—though the results showed the effect was strongest in more severely affected patients.
The study, in 660 people with diabetic macular edema, showed Eylea was the most effective of the three medicines among patients who started the trial with vision of 20/50 or worse. Among patients starting with vision of 20/32 to 20/40, the medicines "showed no apparent differences," the study authors wrote. It was published online Wednesday in the New England Journal of Medicine.
"We're certainly please to hear them recommend our drug in those people who need ti the most but on the other hand I think it's still worth debating what to do in those patients who have a little better vision," Regeneron CEO Leonard Schliefer told CNBC's "Squawk Box" on Thursday.
He noted that Eylea performed substantially better compared to Avastin in terms of improving swelling in the eye.
About 750,000 people in the U.S. have diabetic macular edema, or DME, a leading cause of vision loss, wrote the study authors, led by John Wells of Palmetto Retina Center in West Columbia, South Carolina, and Adam Glassman of the Jaeb Center for Health Research in Tampa, Florida. Regeneron says as many as 2.5 million Americans may have the condition, including 1 million cases that are undiagnosed.
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Lucentis and Eylea are both approved for DME, while Avastin—a cancer medicine also known as bevacizumab—is often used off-label because it works similarly and it's less expensive: $50 a dose for eye indications, compared with $1,950 for Eylea and $1,200 for Lucentis. The dose of Avastin used for eye conditions is about one-five-hundredth the amount used for cancer therapy, explaining the cost difference, the study authors said.
"Given the large difference in cost to patients per dose ... bevacizumab should be considered as first-line therapy in patients with a visual acuity of 20/40 or better," Daniel Martin, of the Cleveland Clinic, and Maureen Maguire, of the University of Pennsylvania, wrote in an editorial accompanying the study, referring to Avastin. Eylea should be used first in patients with vision of 20/50 or worse, they said.