As Biogen gears up for next month’s key FDA advisory committee meeting on Alzheimer’s drug candidate aducanumab, several other areas of its business are flashing warning signs. While executives didn’t want to discuss potential cost cuts on a Wednesday conference call, they said they’re possible down the line if aducanumab doesn’t score an approval.

Biogen is facing competitive pressures in several important business areas amid its critical FDA review. Blockbuster spinal muscular atrophy drug Spinraza is staring down new competition from Roche’s Evrysdi, and in turn sales for the drug fell 10% during the third quarter. One reason? Evrysdi can be dosed at home.

During the COVID-19 pandemic, it’s “understandable” some patients have switched to the Roche option, Biogen CEO Michel Vounatsos said on the company’s Wednesday call. So far, about 200 Spinraza patients have made the jump, he said. Sales for the med slipped to $495 million for the quarter.

Biogen is “confident that over time, Spinraza will remain the foundation of therapy for the treatment of SMA,” Vounatsos said.

But lucrative multiple sclerosis drug Tecfidera, meanwhile, is under even more pressure as multiple generics have launched, causing prices to crater 90%, execs said Wednesday.

Sales of the drug slipped 15% to $953 million, and as a result, the company chopped $700 million off its 2020 revenue guidance at the midpoint.

Now, Biogen expects $13.2 billion to $13.4 billion in global 2020 sales, compared with a prior range of $13.8 billion to $14.2 billion. Vumerity, intended to be a more tolerable follow-up to the successful oral MS drug, hasn’t gained steam, generating just $15 million in the third quarter.

After Biogen reported second-quarter 2020 results, Vounatsos said the drug faced a “critical” stretch ahead. But on Wednesday’s call, he said the medicine’s sales remain “immaterial.”

All of those factors signal that the company is really leaning on its Alzheimer’s disease drug candidate heading into next month’s advisory committee meeting. Guggenheim Securities analyst Yatin Suneja titled his coverage of Biogen’s third-quarter performance “Help Me, Aducanu, You’re My Only Hope.”

Aducanumab is Biogen’s “highest priority,” Vounatsos said, and the company is focused on preparing for the November 6 meeting with the FDA. Execs didn’t offer details about the company’s plan for the meeting or any new data analyses it might present.

Last year, Biogen and its development partner Eisai ended phase 3 trials of the drug early after an interim analysis showed it was unlikely to succeed. Later in the year, though, the companies said a larger analysis warranted an FDA filing. Now, Biogen is preparing for commercialization as the regulatory process plays out.