Biogen MS superstar Tecfidera misses estimates; hit with first confirmed PML case

Biogen Idec's ($BIIB) new multiple sclerosis pill Tecfidera has been on a roll since its launch last year, with more than $1 billion in sales to its credit already. Today, however, the drug hit a couple of speed bumps: Third-quarter sales missed analyst estimates, and the company announced a patient had died after developing a rare brain infection previously linked to MS drugs.

The infection, progressive multifocal leukoencephalopathy (PML) struck a European patient who had been taking Tecfidera for four years, Biogen said. The patient, who started on Tecfidera during clinical trials, then died of pneumonia. "Despite this tragic loss, we believe the overall positive benefit-to-risk profile of Tecfidera remains unchanged," CEO George Scangos said during today's earnings call.

Meanwhile, the drug brought in $787 million for the third quarter, more than double last year's figure, but still short of the $794 million analysts had expected, Bloomberg reports. Biogen shares slid on the news.

Biogen has dealt with the same safety issue before; patients using the company's infused MS drug Tysabri developed PML soon after its 2005 launch. The company took Tysabri off the market, and when it was relaunched in 2006, it came with a risk-management program and prescribing restrictions. The powerful drug has sold well despite the risks, with $501 million in sales for Q3. It was the world's fifth-best-selling MS drug last year.

Since then, the company has recommended that patients be tested for the JC virus, to help weed out those at higher risk of PML. The FDA updated warnings on the drug to note that the risk is highest in patients who use Tysabri for longer than three years.

Analysts weren't too fussed about the Tecfidera miss. "It's not a massive quarter, but it's a solid quarter, and it's encouraging that the MS franchise continues to grow," Bernstein analyst Geoffrey Porges told Bloomberg. But in an interview with Reuters, Porges also pointed out that Biogen's various MS drugs are not only competing with other companies' treatments, but with each other. "[Y]ou have to wonder, is there enough incremental revenue to support continued growth or are they just cannibalizing the rest of their franchise every time they launch a new product," he said.

A new entry for that franchise won approval during the quarter, in fact; Plegridy nabbed clearance in the EU in July and in the U.S. in August. A long-acting form of its popular injectable MS treatment Avonex, Plegridy is expected to claw its way to blockbuster status, with as much as $2 billion in peak sales. The market share fight will be tough, however, requiring Biogen to woo patients away from Avonex and other short-acting interferon treatments.

And as for Tecfidera itself, the shortfall may have been as much about over-estimating as it is about Tecfidera's performance. "We've always expected that Tecfidera's growth rate would moderate over time," Biogen commercial chief Tony Kingsley said during today's earnings call.

- see the Biogen release
- get more from Reuters
- read the Bloomberg story

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