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.
About three-quarters of patients with diabetic macular edema have vision of 20/40 or better when they come in for treatment, Martin and Maguire said, meaning Eylea should be top choice in a quarter of all patients. In the study, 51 percent of the patients had 20/32 to 20/40 vision.
The study was sponsored by the National Institutes of Health, whose trial several years ago pitting Avastin and Lucentis against one another in another eye condition, age-related macular degeneration, sent Regeneron's stock oscillating. The study, called Comparison of AMD Treatment Trials, or CATT, found the medicines were equally effective, leading investors to fear the less expensive Avastin would take more market share. Those results were published in the New England Journal of Medicine in 2011.
Eylea's revenue has continued to grow; the drug drew $1.74 billion in U.S. sales for Regeneron in 2014, primarily from its use in wet AMD. It was approved for DME in July. Lucentis, approved for both indications, drew 1.7 billion Swiss francs ($1.8 billion) for Roche, while Avastin brought in 6.42 billion Swiss francs (that includes its use in cancer).
Cowen analyst Phil Nadeau estimates Eylea could draw $730 million from U.S. sales in DME in 2019, contributing to total sales of the drug that year of an estimated $2.8 billion.
"In this independent, government-sponsored diabetic macular edema study, Eylea provided significantly greater efficacy, despite one fewer injection and fewer laser treatments than comparators," George Yancopoulos, Regeneron's chief scientific officer, said in a statement. Laser treatment is a common therapy for patients with DME, though drugs have become a first-choice option among doctors.
Yancopoulos noted the improvements with Eylea "were particularly apparent in the group with moderate or worse vision loss at the start of the trial, where there was a greater opportunity to demonstrate gains in vision."
Patients on Eylea also showed a bigger decrease in retinal thickness, a hallmark of the condition, than those on the other medicines.
The difference between Eylea and Lucentis "in a small group of patients with more severe vision loss has not been seen in previous studies," Terry Hurley, a spokesman for Roche's Genentech, said in an e-mailed statement. The results "need further evaluation to better understand the potential impact of factors such as the duration and severity of their diabetes and their overall health."
"We believe doctors have the right to choose the treatment option they think is best for their patients," Hurley said. "Although important, results from a single trial with one year of data should be interpreted in the context of extensive existing evidence and clinical experience."
Adnan Butt, an analyst with RBC Capital Markets, said the results were better than expected for Regeneron.
The study showed a "vision benefit overall for Eylea, but a key benefit in a pre-specified subset," he wrote in a research note.