Genzyme plans to resubmit multiple sclerosis drug candidate to the FDA

Researchers in the Genzyme labs. (Globe staff file photo/Suzanne Kreiter)
Researchers in the Genzyme labs. (Globe staff file photo/Suzanne Kreiter)

Nearly four months after the Food and Drug Administration rejected a multiple sclerosis drug developed by Genzyme, citing the clinical trial’s design and a risk of serious side effects, the Cambridge biotech Monday said it will resubmit an application for approval to the agency.

Rather than appeal the FDA’s decision, as expected, Genzyme  said it will file an updated license application for the drug candidate, called Lemtrada, in the second quarter. The new submission will specifically address issues raised by the FDA in its Dec. 27 decision turning down the experimental treatment, Genzyme said in a statement.

The move follows a series of discussions early this year between Genzyme executives and regulators in the neurology products division of the FDA’s Office of Drug Evaluation, said Genzyme spokeswoman Erin Walsh. She declined to elaborate on the talks and said company officials wouldn’t comment until after they resubmitted their application. But she did say the drug maker has no plans to conduct additional clinical studies before the FDA rules.

“We had constructive discussions with the FDA that have led us down this path where we’re resubmitting our application rather than filing an appeal,” Walsh said. “We don’t believe further trials are needed prior to an approval. But we would entertain any kind of post-approval commitments” to the FDA, including possible further tests of the drug, she said.

Agency officials similarly would not talk about Genzyme’s plans to resubmit its Lemtrada application. The agency rejected the drug for use in the United States, even though it had been approved by regulators in Europe, Canada, and Australia. The decision was criticized by MS patients, who said the drug had proven effective in clinical trials, and by investors who own a special class of stock that is tied to Lemtrada’s regulatory and sales milestones.

“We are not able to discuss any aspect of a drug application that is under agency review,” said FDA spokeswoman Sandy Walsh. In November, an FDA advisory committee warned that the drug’s side effects could include rashes, bleeding, and even thyroid cancer.

Genzyme scientists spent more than a decade developing Lemtrada for the treatment of multiple sclerosis, a disease that affects the central nervous system. About 1,700 patients were involved in clinical testing of the drug. More than 2.3 million people have been diagnosed with MS worldwide, including about 400,000 in the United States.

The potential of that market, and anticipation that Lemtrada would be approved in the United States, was a major attraction for French drug maker Sanofi SA, which paid $20.1 billion to acquire Genzyme in 2011. As part of that deal, Sanofi agreed to reward former Genzyme stockholders if the drug achieved certain milestones in the US market.

Rob Weisman covers life sciences and healthcare for the Boston Globe. Email him at [email protected].
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