Biogen has shown “exceptionally persuasive” evidence that its experimental Alzheimer’s disease drug is effective, US Food and Drug Administration staff said on Wednesday, elevating its chances of a swift approval and sending company shares soaring.
An FDA approval could come by March, which would make the drug, aducanumab, the first new treatment for the disease in decades and the first that appears to be able to slow progression of the fatal, mind-wasting condition that affects millions of people.
Biogen’s shares jumped $97.02, or nearly 40 percent, to $344.99.
The agency’s documents were released ahead of a meeting on Friday of outside experts who will review, and decide whether to recommend approval of, aducanumab, an antibody designed to remove amyloid plaques from the brain.
“Briefing documents suggests a positive Advisory Committee vote, which bodes well for approval,” Guggenheim analyst Yatin Suneja said in a research note.
FDA drug reviewers said results from one pivotal trial of aducanumab were persuasive and strongly positive. They acknowledged that a second large trial did not succeed, but maintained that it did not detract from the findings of the positive study. The FDA is not obligated to abide by its expert panel recommendations, but typically does.
Cambridge, Massachusetts-based Biogen in October last year revived its plans to seek approval for aducanumab, months after it had said that an independent futility analysis of the two studies showed they were unlikely to succeed.
Biogen said it changed plans after a new analysis showed a high dose of the drug could slow the disease’s progression.
The FDA staff said data from one of the trials “provides the primary evidence of effectiveness as a robust and exceptionally persuasive study demonstrating” a clinically meaningful treatment effect.
The drug was jointly developed with Japan’s Eisai Co Ltd, whose shares jumped 45 percent.