Tysabri’s PML Count Climbs to 28, and Some Reflections From Biogen Idec’s Departing CEO

about the strategy and get some fresh views.”

On his plans after June:

“A lot of people don’t think I take advice very well, but one of the pieces of advice I got from a lot of people was—finish what you’re doing, clear your head, take some time, and consider the different options on what you plan to do. That’s what I intend to do.”

On the status of competing MS drugs:

“Anybody else’s delay is our good news.” Given the well-known PML risk with natalizumab, Merck KGaA’s cladribine, and Novartis’ FTY-720, those companies will have to deal with more regulatory scrutiny, Mullen said. “The safety scrutiny has gone up and up and up. In the U.S., everyone is going to have to have a REMS [risk evaluation and mitigation strategy]. It might be modest, or it might be as restrictive or tight as Tysabri’s.”

“Certainly an oral product will [find] a lot of interest in the marketplace. On the other hand, that product also has some fairly significant safety issues and it’s going to have a REMS program. I think the established safety and efficacy profile of the ABCRs [Avonex, Betaseron, Copaxone, & Rebif, the standard treatments] is such that they are the first-line therapies, and it will be true for some period of time.”

On how to mitigate the risk of PML by testing for biomarkers to gauge a patient’s vulnerability:

“We have done, since 2005, a tremendous amount of work to look at anything and everything to mitigate the risk around this product. Certainly the JCV antibody test, we think, is the most solid diagnostic we have seen. The data as we developed it have tipped over some of the widely held beliefs that essentially everybody here was going to be JCV antibody positive, because we’ve all been exposed to JC virus [the virus that crosses into the brain and causes PML]. It looks like it’s more like half of us. We also have serum samples from patients with PML, and they were all JCV positive. So it’s a solid assay.

“But then there’s chatter about what does it mean for JCV antibody positive patients? You really have to put yourself in the shoes of those patients. Right now, Tysabri is a third or fourth line product. The 48,000 patients who are on it have failed one or more therapies. They aren’t doing well. Their options are being exhausted rapidly. When they look at being JCV antibody positive or negative, the question is, ‘How am I doing on the product?’ If I’m doing well on the product, they’ll be left on the product, and probably monitoring will increase. The more we can learn about other risk factors will be helpful. For those who are negative, it opens up the question of whether we should

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.