FDA grants accelerated approval for Biogen’s ALS drug tofersen

FDA-grants-accelerated-approval-for-Biogen-s-ALS-drug-tofersen.jpg
Pic:getty/kotofeja (Getty Images)

The FDA has granted accelerated approval for Biogen’s Qalsody (tofersen): making it the first treatment to target a genetic cause of ALS.

It also marks a ‘pivotal moment’ in ALS research as it shows neurofilament can be used as a surrogate market reasonably likely to predict clinical benefit in SOD1-ALS, which Biogen says will help accelerate drug development in the area.

Qalsody will be made available for shipment in the US to healthcare providers over the next week.

The approval is a boost for Biogen, which hopes to see three big drug launches in 2023.

First-of-a-kind treatment

The FDA has approved antisense oligonucleotide Qalsody (tofersen) 100 mg/15mL injection for the treatment of amyotrophic lateral sclerosis (ALS) in adults who have a mutation in the superoxide dismutase 1 (SOD1) gene.

This indication is approved under accelerated approval based on reduction in plasma neurofilament light chain (NfL) observed in patients treated with Qalsody (Neurofilaments are proteins that are released from neurons when they are damaged, making them a marker of neurodegeneration).

Qalsody was evaluated in a 28-week, randomized, double-blind, placebo-controlled clinical study in 147 patients with weakness attributable to ALS and a SOD-1 mutation confirmed by a central laboratory. The study randomly assigned 108 patients in a 2:1 ratio to receive treatment with either Qalsody 100 mg (n = 72) or placebo (n = 36) for 24 weeks (three loading doses followed by five maintenance doses).

The participants were approximately 43% female; 57% male; 64% White; and 8% Asian. The average age was 49.8 years (range from 23 to 78 years).

Patients receiving Qalsody had nominally significant reductions in plasma NfL concentration at Week 28 compared to the placebo arm. "The findings are reasonably likely to predict a clinical benefit in patients," said the FDA as it announced its decision.

Under the accelerated approval pathway, the ongoing Phase 3 ATLAS study of tofersen in people with presymtomatic SOD1-ALS will serve as the confirmatory trial.

According to the Centers for Disease Control and Prevention, around 16,000 - 32,000 Americans are currently living with ALS. Approximately 2% of ALS cases are associated with mutations in the SOD1 gene (equating to around 500 patients in the US).

“For more than a decade, Biogen has been steadfast in our commitment to pursuing treatments for ALS, and I want to thank the scientists as well as the entire ALS community who have all worked tirelessly to bring this first-of-its-kind treatment to people with SOD1-ALS,” said Christopher A. Viehbacher, President and CEO of Biogen, welcoming the FDA approval.

“It also marks a pivotal moment in ALS research as we gained, for the first time, consensus that neurofilament can be used as a surrogate marker reasonably likely to predict clinical benefit in SOD1-ALS. We believe this important scientific advancement will further accelerate innovative drug development for ALS.”

Biogen shuffles pipeline to focus on three big launches

On Tuesday (April 25), Biogen released its Q1, 2023 results: affirming its full year guidance for the year.

Having received accelerated approval for Alzheimer’s drug Leqembi (lecanemab-irmb) with partner Eisai at the start of this year, Biogen is expecting an FDA decision on traditional approval in July. The drug is also under priority review in Japan and China and review for traditional approval in the EU.

Meanwhile, it is also expecting a decision from the FDA on its New Drug Application for Zuranolone for major depressive disorder and postpartum depression in August.

However, it has also announced that it will deprioritize certain programs in gene therapy, stroke and ophthalmology as part of its R&D pipeline optimization.

It will terminate its involvement in the development of BIIB093 (glibenclamide IV), currently in a Phase 3 study for large hemispheric infarction and a Phase 2 study for brain contusion, and has informed partner Remedy Pharmaceuticals of its decision (Remedy has 30 days to exercise its reversion right to assume development of both programs).

The company will also pause the initiation of a Phase 2b study for BIIB131 (TMS-007) for acute ischemic stroke and is assessing whether to initiate this study. It is also discontinuing development of BIIB132 in spinocerebellar ataxia type 3.