UPDATED: Biogen sees 'unlikely' link between Tecfidera and patient's demise

Biogen Idec ($BIIB) had a bumpy day on Wall Street Monday. A report from BioPharm Insight noted that a patient who had taken Biogen's new multiple sclerosis drug Tecfidera had died, prompting a quick drop of about 3% in the biotech group's stock price, which recovered to about even later in the day.

A Biogen spokeswoman told Reuters that the death of the 59-year-old woman occurred two weeks after she stopped taking Tecfidera because of gastrointestinal problems. The MS patient had suffered from a form of pneumonia prior to her death. The news service reported that the death was unrelated to the GI problems, and the company said that it is "unlikely" that Tecfidera caused the fatal case. 

The drama underscores the high visibility of Tecfidera, for which analysts have projected eventual peak sales of more than $3 billion. As long as the safety profile of the therapy remains within an acceptable range, Tecfidera could become the best-selling drug in the growing class of oral MS drugs, which includes such meds as Aubagio from Sanofi ($SNY) and Novartis' ($NVS) Gilenya.

ISI analyst Mark Schoenebaum wrote to investors that he viewed the death as a "non-issue" for the company's performance. The company told the top analyst that it is "still gathering info" on the case.

Based in part on the promise of Tecfidera, Biogen has mounted a comeback over the past several years under the leadership of CEO George Scangos. In a hot market for biotech stocks, Biogen's shares have sizzled and jumped nearly 63% over the past 12 months through Monday, July 22.

Tecfidera is perhaps the most anticipated drug from the Weston, MA-based biotech heavyweight since the launch of the MS therapy Tysabri, which the FDA initially approved in November 2004. Biogen pulled that drug from the market in 2005 after three patients in clinical trials suffered progressive multifocal leukoencephalopathy (PML) brain infections and two of them died.

Tysabri was reintroduced in 2006 and has gone on to become a blockbuster drug, with tests now available to assess the risk of PML prior to treatment. Yet the issue showed how it can take a long time to dig out from a safety problem with a new drug.

- here's Reuters' article
- and StreetInsider's update

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