Biogen's sales slide on Spinraza, Tecfidera as pivotal Alzheimer's decision nears

As Biogen awaits a key FDA decision on aducanumab, other parts of the company's business faced challenges in the fourth quarter. (Biogen)

As Biogen nears a pivotal FDA decision on its closely watched Alzheimer’s disease drug candidate, other parts of the company’s business are sputtering—outlining just how important aducanumab is for the drugmaker in the near-term.  

U.S. sales for Spinraza, the company’s blockbuster spinal muscular atrophy drug that launched in early 2017, plummeted by 34% in the fourth quarter compared with the same period in 2019—a worrisome sign for a relatively new launch, especially one Biogen has been leaning on so heavily.

A gene therapy rival from Novartis—and a new oral option from Roche—have launched since Spinraza’s debut, ratcheting up competitive pressure that was “exacerbated” by the pandemic, execs said on a conference call Wednesday. 

The company is “watching this trend very carefully,” CEO Michel Vounatsos said on the analyst call. The “majority” of the impact is the COVID-19 pandemic, he said, as many patients opted against going to treatment centers for their Spinraza doses. Some sites are closed and others have limited capacity and staffing, he noted, though the company did see some “rebound in demand” at the end of 2020.

Meanwhile, the pandemic is “accelerating switches to alternative treatment,” Vounatsos noted.

The oral administration route for Roche’s Evrysdi is “more attractive” for some patients during the pandemic, CFO Michael McDonnell acknowledged. Still, the company believes Spinraza has a “very strong efficacy and safety profile and will continue to be a foundation of care,” McDonnell said.

Fourth-quarter Spinraza sales fell 34% in the U.S. to $160 million, but sales outside the U.S. grew 13% to $339 million. In all, the drug pulled in $2.05 billion during 2020, a slight decline from the year before.

RELATED: Roche's low-price Evrysdi will take 'meaningful' SMA share from Biogen's Spinraza: analyst 

Aside from Spinraza, Biogen’s revenue for blockbuster multiple sclerosis drug Tecfidera fell 13% to $3.84 billion last year thanks to generic competition. New launch Vumerity hasn’t picked up enough steam to make up the difference, generating just $64 million for the year. As for Tecfidera, Biogen expects a “sharp decline” in sales in 2021. 

Biogen also earns some revenues on Rituxan, a Roche-partnered biologic med for numerous indications that's now facing biosimilars. Biogen’s share of sales for that drug and another Roche med—Gazyva—slipped 29% to $1.13 billion in 2020. For 2021, Biogen expects “significant erosion” of Rituxan.

All told in 2020, Biogen’s sales fell 6% to $13.45 billion. 

RELATED: Biogen stands to lose billions in Tecfidera sales next year, analyst says after new court ruling 

Amid those challenges, the company could be nearing a launch for Alzheimer’s disease drug aducanumab—if the FDA approves the medicine. An FDA advisory committee voted against it, but investor confidence grew last week when the agency extended its review for three months to further weigh the data.

Already, hundreds of sites are ready to start with treatment if the drug is approved, execs said Wednesday. The company built revenue assumptions for the drug into its 2021 guidance as a “best reflection of how we see the business moving forward,” Vounatsos said. 

Biogen is engaging with “many stakeholders” in its discussions around pricing and is further considering the cost of society from Alzheimer’s disease.

While Biogen sees aducanumab as the near-term “catalyst” for growth, McDonnell said the team believes the company can grow into the future based on its pipeline. The company expects four phase 3 readouts and four phase 2 readouts this year. But as it released fourth-quarter results, the company also cut a Parkinson's drug candidate from its pipeline.