Bristol Myers Squibb (BMY 0.43%) announced on Thursday that the Food and Drug Administration has approved Zeposia (ozanimod) for treating adults with relapsed multiple sclerosis (MS), an autoimmune disease where the body's immune system attacks the protective myelin sheathes that cover its nerves. The FDA approval was based on two large late-stage clinical studies in which Zeposia demonstrated higher efficacy than Biogen's MS drug Avonex.

A second effort

Celgene first filed for FDA approval of ozanimod in 2018. However, the FDA sent the biotech a Refusal to File letter stating that the application for the drug wouldn't even be considered because the submission didn't include all of the required information for a review. 

Businessman holding card that has "FDA approved" printed on it

Image source: Getty Images.

Celgene resubmitted its application in March 2019, less than three months after Bristol Myers Squibb announced its plans to acquire the biotech. That acquisition closed in November.

Blockbuster potential -- eventually

Zeposia's efficacy and convenience as a once-daily oral medication should appeal to physicians and patients. Celgene estimates that the drug could generate peak annual sales of between $4 billion and $6 billion if it also gains approval as a treatment for two other autoimmune diseases -- Crohn's disease and ulcerative colitis. Analysts forecast that Zeposia will rake in around $1.6 billion annually by 2024.

However, its path toward blockbuster status won't start immediately. Bristol Myers Squibb stated that it's delaying the launch of Zeposia due to the COVID-19 pandemic. The drugmaker said that it will monitor the situation and consult with the neurology community before deciding on the specific timing of the drug's launch.