The FDA has approved an expanded indication for Genzyme’s leukemia drug Lemtrada to treat relapsing multiple sclerosis, 11 months after it initially turned down the company’s sBLA due to safety concerns.

The approval of Lemtrada (alemtuzumab) requires a boxed warning about serious and sometimes-fatal autoimmune conditions, life-threatening infusion reactions, thyroid cancer, melanoma and lymphoproliferative disorders. The drug also requires a Risk Evaluation and Mitigation Strategy plan, which includes monitoring of patients for four years after the last infusion of the drug.

Sanofi subsidiary Genzyme said the drug generally is recommended for use only in patients who have not responded well to two or more alternative MS therapies.

One of the key differences that set Lemtrada apart from other therapies is its dosing and administration schedule, said company spokeswoman Erin Pascal. While many other MS drugs must be administered daily or weekly, Lemtrada is given intravenously for the first five days, followed by a second three-day course an entire year later, Pascal said. 

The drug already is approved for relapsing MS in Europe, Canada and Australia. It also is approved in the U.S. to treat B-cell chronic lymphocytic leukemia. The FDA’s latest action on the product follows its rejection in December 2013 based on serious safety concerns. In a complete response letter, the FDA asked Genzyme to conduct new comparator trials with a different design.

While Genzyme declined to conduct new trials, it did provide the FDA with additional analyses to satisfy regulators’ concerns of serious adverse events, the company said. It also included data from the same two pivotal Phase III trials included in the original submission, which compared Lemtrada to Merck and Pfizer’s Rebif (high-dose subcutaneous interferon beta-1a).

In the trials, Lemtrada proved significantly better at reducing annualized relapse rates both in treatment-naïve and -experienced patients, the company said. — Lena Freund

Originally appeared in Drug Industry Daily, the pharmaceutical industry’s number one source for regulatory news and information. Click here for more information.