Biogen leaves analysts guessing on aducanumab
- Biogen left Wall Street in the dark on Tuesday, declining to answer analyst questions about potential data readouts on its closely watched Alzheimer's disease drug, aducanumab. The big biotech did, however, announce plans to initiate another late-stage study that will evaluate whether early use of aducanumab can prevent or delay clinical onset of the disease.
- The questions came as part of Biogen's fourth quarter earnings call. Product revenue increased 4% year over year to reach $2.83 billion for the quarter, while total revenue grew 7% to hit $3.53 billion. Biogen expects 2019 revenue to range between $13.6 billion and $13.8 billion.
- A $115 million inventory build helped the biotech's multiple sclerosis business slightly exceed Wall Street expectations for the quarter. Spinraza, on the other hand, didn't fare as well. The spinal muscular atrophy drug has been a key growth driver for Biogen, but missed consensus estimates due to weaker-than-forecasted sales outside the U.S.
A multi-billion-dollar opportunity awaits any company able to treat the underlying causes of Alzheimer's. Biogen has one of the few late-stage therapies aimed at that elusive indication, hence Wall Street's heightened interest.
Two Phase 3 studies of aducanumab in early Alzheimer's disease kicked off in 2015 and should wrap up at the beginning of next year.
Analysts are itching for more details — particularly because it's the biotech's most important pipeline asset. But attempts to glean information about releasing interim data before the primary readouts did not succeed on the investor call.
"I realize there's a policy of not commenting on it, but once you do get a notification from the [data and safety monitoring board], given the sheer materiality of this, will you not put out a statement?" Evercore ISI's Umer Raffat asked on Tuesday's earnings call.
"I'm sorry, but we just can't comment on interim analyses," said Al Sandrock, Biogen's chief medical officer.
Where Biogen did provide details was on its newly announced pivotal trial evaluting how early aducanumab treatment affects clinical onset of Alzheimer's.
Sandrock noted that Biogen considered doing this study for the last few years at the encouragement of advisors and investigators. The trial also fits into the company's lifecycle management strategy, and comes at an opportune time given recent Food and Drug Administration guidance on drug development for early Alzheimer's disease.
"We believe one day the standard of care will be to treat with amyloid-lowering drugs as early as possible, and this trial will go a long way toward informing that," Sandrock said.
Leerink's Geoffrey Porges suggested the Phase 3 trial announcement may spur some investors to believe Biogen is more bullish on its Alzheimer's prospects. "Investors are likely to react positively to this disclosure, despite the incremental concentration of pipeline risk, and cost, that it confers," he wrote in a Jan. 29 investor note.
Porges acknowledged, though, that Biogen will face more conversations about interim analyses and the potential competition posed by Roche and AC Immune's Alzheimer's drug, crenezumab.
"[T]here was no suggestion on the call that this decision was based on any evidence or signal from the pivotal trials," he wrote of the planned Phase 3 study.
Aducanumab is a monoclonal antibody that selectively binds to aggregates of beta-amyloid, a protein that many scientists have hypothesized contributes to the neurodegeneration seen in Alzheimer's patients.
Crenezumab also targets beta-amyloid. The drug has an upcoming futility test analysis that could spook Biogen investors, though analysts and Biogen have warned against drawing broad conclusions.
"I'd be cautious about too much read-through," Sandrock said on the earnings call, adding that aducanumab and Roche's drug differ in their binding sites, selectivity and effect on amyloid plaque burden.
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