Biogen shares up; Alzheimer's drug shows promise

In a field littered with failures, Biogen Idec offered some potential hope Tuesday. The company said its experimental medicine for Alzheimer's disease showed promise in an early study, prompting it to move "aggressively" into the most advanced stage of studies.

Biogen shares rose more than 6 percent in early market trading on the interim phase 1b results. (Click here to get a real-time Biogen stock quote.)

Biogen's drug, BIIB037, aims to slow the progression of Alzheimer's by binding to buildups known as amyloid plaques and clearing them from the brain. The company said Tuesday that the interim analysis showed the drug reduced amyloid levels in the brain "in both a dose- and time-dependent fashion."

The drug also showed a positive effect on cognition compared with a placebo after 54 weeks in the study, Biogen's head of research and development, Doug Williams, said in a presentation at Deutsche Bank's BioFEST conference in Boston.

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"You've got me tongue-twisted with the Alzheimer's data," Deutsche Bank analyst Robyn Karnauskas told Williams later in the presentation.

The positive data are a surprise both because Alzheimer's has been such a tough field—with recent failed studies from Pfizer, Johnson & Johnson and Eli Lilly—and because the study was in such an early phase; its primary goal was to assess safety, with amyloid reduction and cognition as secondary or exploratory endpoints.

A worker in a Biogen lab.
Suzanne Kreiter | The Boston Globe | Getty Images
A worker in a Biogen lab.

The drug did show some side effects in what's known as ARIA, or amyloid-related imaging abnormalities, a safety concern seen with other amyloid-clearing drugs and sometimes in Alzheimer's patients without treatment. Williams said some ARIA was seen in patients taking placebo, though there was a higher incidence in those on the drug, and it was mostly mild to moderate.

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"We believe we have a safety window to work with," Williams said. The study is continuing, and the company will explore some additional doses, he said. Biogen plans to present full data at an upcoming medical meeting, most likely the Alzheimer's & Parkinson's Diseases Congress in March in Nice, France, Williams said.

More than 35 million people worldwide have dementia, of which Alzheimer's is the most common cause, according to the World Health Organization. That number is expected to almost double every 20 years, to 66 million in 2030. In the U.S., more than 5 million people are living with the disease, according to the Alzheimer's Association.

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"Alzheimer's disease is a veritable graveyard of failed development efforts so a tempered approach is advised here," Chris Raymond, an analyst with Robert W. Baird, wrote in a research note. "That said, this is obviously a huge unmet need, and as BIIB037 approaches phase 3, we think it's plausible that an increasing premium for this opportunity has to start working its way into the stock."

Williams also cautioned Biogen has a ways to go in moving the compound forward.

"We're going to try to replicate what we've seen in this relatively small study," he said. "Based on these results, we're planning very aggressively to start the phase 3 program."

Raymond put it another way: "Bottom line—too early to pop the champagne corks just yet, but definitely a positive development."