Biogen MS blockbuster Tecfidera earns high marks for safety

Biogen's ($BIIB) multiple sclerosis drug Tecfidera has racked up $1.38 billion in sales since its launch last April, and now the company can claim another feather in the drug's cap: It has the best safety profile of any of its peers. That's the conclusion of a new report out from AdverseEvents, which analyzes side-effects data filed with the FDA.

In general, older interferons used to treat MS, such as Rebif from Pfizer ($PFE) and EMD Serono, Biogen's Avonex, and Bayer Healthcare's Betaseron, are not as safe as newer entrants to the market, AdverseEvents found. Betaseron in particular had the highest reported levels of disabling or fatal side effects. As for the question of whether interferon-based drugs are linked with suicides--a point of controversy in the past--AdverseEvents found that both Rebif and Novartis's ($NVS) Extavia, also an interferon, were associated with depression and suicidal behavior.

Although the AdverseEvents analysis found that Tecfidera had a higher association with gastrointestinal upset than did its rivals, the drug had among the lowest overall quantity of reported adverse events, and the fewest that were considered serious enough to require hospitalization. On the AdverseEvents "RxScore"--a scale the firm uses to indicate safety, with 100 representing the highest risk--Tecfidera came out with the top score of 33.11. Novartis' Gilenya, once considered Tecfidera's biggest threat, has been dogged with safety concerns over the past year, and AdverseEvents found that patients taking it may indeed need to be monitored for lymphocyte and cardiac abnormalities.

The FDA's database of adverse events, which the agency made available to the public as part of its new openFDA initiative, includes reports from doctors, patients and other healthcare providers. There's no way to tell if the side effects are caused by the drugs being reported, however. That makes it difficult for the average person to make heads or tails of the data. AdverseEvents uses logic, math and software to sift out the key details.

Despite Tecfidera's good showing, the side effect news wasn't all good for Biogen. Both Avonex and Biogen's newer player, Tysabri, yielded several reports of "cognitive disorder" and "memory impairment," according to AdverseEvents. Biogen bought out full rights to Tysabri last year, helping to push its proceeds from the drug up 41% in the first quarter to $441 million. But the company admitted during its earnings report in April that Tysabri sales are slipping, and demand for Avonex appears to be softening, too.

Early signs indicate that Tecfidera's strong performance may be enough to make up for the shortfall. Biogen's total revenues in the first quarter hit $2.1 billion--a 50% increase over the same period a year ago.

- download the AdverseEvents report here