Sanofi’s Genzyme unit has finally got the thumbs-up from the US Food and Drug Administration for its multiple sclerosis therapy Lemtrada.

At the end of last year, the agency issued a complete response letter for Lemtrada (alemtuzumab) saying Genzyme had failed to submit evidence showing that its benefits outweigh its serious adverse effects. The company disagreed vehemently but resubmitted the drug which has now got the thumbs-up 14 months after getting European approval.

Because of its safety profile, the FDA noted that use of Lemtrada should generally be reserved for patients who have had an inadequate response to two or more MS drugs. The label includes a boxed warning noting a risk of autoimmune conditions, serious and life-threatening infusion reactions and malignancies including thyroid cancer, melanoma and lymphoproliferative disorders.

The approval is based on Phase III trials comparing Lemtrada with Merck KGaA’s Rebif (interferon beta-1a) which showed that it was significantly more effective than the latter at reducing annualised relapse rates. hours. The first treatment course is administered via intravenous infusion on five consecutive days, and thenthree consecutive days 12 months later.

Timothy Coetzee, chief advocacy, services and research officer at the National MS Society, said “we are pleased that the voices of the MS community have been recognised and that people with relapsing MS will now have access to a new, needed treatment option”.

The approval means that Genzyme now has two MS drugs to market across the pond, as its oral treatment Aubagio (teriflunomide) got the green light in September 2012.