European Commission authorizes Qalsody for SOD1-ALS

The European Commission has granted marketing authorization under exceptional circumstances for Qalsody to treat those with amyotrophic lateral sclerosis associated with a mutation in the superoxide dismutase 1 gene.

According to a press release from Biogen, Qalsody (tofersen), an antisense oligonucleotide, targets superoxide dismutase (SOD1) mRNA to reduce protein production, became the first treatment approved in the European Union to target a genetic cause of ALS.

The FDA had previously approved the drug for the same condition in April 2023, based on reduction in plasma neurofilament light chain (NfL), a blood-based biomarker which indicates neurodegeneration.

“The European Commission’s approval of Qalsody is a testament to the unwavering dedication of the ALS community who have worked together over the past two decades to bring forward this important new treatment for SOD1-ALS,” Stephanie Fradette, PharmD, head of the neuromuscular development Unit at Biogen, said in the release. “We are working with the medical community and local authorities to bring Qalsody to people living with SOD1-ALS across the region as quickly as possible.”

Approval was based on data from the phase 3 VALOR clinical trial, a randomized, double-blind, placebo-controlled study. A total of 108 individuals were randomized 2:1 to receive either 100 mg Qalsody or placebo over 24 weeks, with the primary efficacy endpoint change from baseline to week 28 in the ALS Functional Ratings Scale-Revised (ALSFRS-R) total score.

Data showed, at week 28, mean plasma NfL was reduced by 55% in those given tofersen compared with an increase of 12% in the placebo group. The drug was also well-tolerated, with common adverse events being muscle and joint pain, fatigue, fever and increased protein and/or white blood cell count.

Biogen additionally stated in the release that Qalsody is being investigated in another phase 3 study (ATLAS), to evaluate its ability to delay clinical onset in presymptomatic individuals with a SOD1 genetic mutation and biomarker-led evidence of disease activity.