Biogen, Ionis discontinue development of ALS drug

May 16, 2024

Biogen and Ionis Pharmaceuticals announced that they will halt development of BIIB105, an investigational antisense oligonucleotide for amyotrophic lateral sclerosis (ALS), based on phase 1/2 study results.

The ALSpire study aimed to assess BIIB105's ability to reduce ataxin-2 (ATXN2) protein expression in cerebrospinal fluid, a target thought to influence ALS progression. While BIIB105 significantly reduced ATXN2 levels, it failed to lower plasma neurofilament light chain, a biomarker for neurodegeneration, and did not improve clinical outcomes related to function, breathing or strength.

The ALSpire study was a randomized, placebo-controlled trial involving 99 adult ALS patients. Participants received BIIB105 or a placebo for 3 to 6 months, with a follow-up open-label extension. Common adverse events for BIIB105 included procedural pain, headache, and falls, with a higher discontinuation rate due to adverse events compared to the placebo group. Longer-term data showed sustained ATXN2 reduction but no impact on NfL or clinical outcomes over more than 40 weeks.

Last year, Biogen and Ionis found success with Qalsody, when it was approved by the FDA for treating an ultra-rare form of ALS with a mutation in the superoxide dismutase 1 (SOD1) gene. This mutation affects approximately 330 people in the U.S. Qalsody, an antisense oligonucleotide that blocks the production of the SOD1 protein and prevents its clumping and subsequent nervous system damage, became the first approved treatment targeting a genetic cause of ALS.