CAMBRIDGE, Mass. — December 22, 2025 — Leads & Copy — Biogen Inc. (Nasdaq: BIIB) announced the publication of final results from the Phase 3 VALOR study and its open-label extension (OLE) study in JAMA Neurology, evaluating QALSODY® (tofersen) for superoxide dismutase 1 (SOD1) amyotrophic lateral sclerosis (ALS) treatment with over 3.5 years of follow-up.
The data indicates that early QALSODY initiation was associated with a slower decline in clinical function, breathing, and strength measures. It also showed a reduction in the risk of death or permanent ventilation. Sustained reductions in neurofilament, a neurodegeneration marker, validate the clinical results, demonstrating QALSODY’s impact on SOD1-ALS biology.
According to Stephanie Fradette, Pharm.D., Head of the Neuromuscular Development Unit at Biogen, the VALOR/OLE data emphasizes the potential to impact ALS course and improve the outlook for people living with the disease. Treatment-driven reductions in neurofilament are being used as an early decision-making endpoint to accelerate future research.
QALSODY 100 mg/15mL injection is approved for amyotrophic lateral sclerosis (ALS) treatment in adults with a mutation in the superoxide dismutase 1 (SOD1) gene. In the U.S., QALSODY received accelerated approval based on plasma neurofilament light chain (NfL) reduction. Continued approval may be contingent upon clinical benefit verification in confirmatory trials. QALSODY has been approved in 44 countries.
The VALOR study was a six-month Phase 3, randomized, double-blind, placebo-controlled study evaluating tofersen 100 mg in adults with ALS associated with a SOD1 mutation. Of the 108 participants randomized in VALOR (n=72 to tofersen 100 mg and n=36 to placebo), 95 enrolled in the OLE. The median follow-up was 4.9 years (range 3.6-5.4) at OLE completion.
According to Timothy Miller, M.D., Ph.D., principal investigator of VALOR and ALS Center Director at Washington University School of Medicine in St. Louis, 27% of study participants in the early-start group experienced improvements in muscle strength over ~3 years. “This just does not happen in ALS… today these conversations include the potential for how to maximize improvement.”
The most common adverse events (AEs) were headache, procedural pain, fall, back pain, and extremity pain. Serious neurological AEs of myelitis or radiculitis, papilledema and/or increased intracranial pressure, and chemical or aseptic meningitis were reported in nine participants (8.7%). These events were manageable with standard of care and resolved.
Merit Cudkowicz, M.D., co-principal investigator of the VALOR trial and co-founder of the Northeast ALS Consortium, said that early initiation of QALSODY is associated with a 3.4-year extension of event-free-survival. “This makes all of us very excited about what we will learn from the presymptomatic ATLAS study where there is a possibility we could delay the onset of disease.”
QALSODY is an antisense oligonucleotide (ASO) designed to bind to SOD1 mRNA to reduce SOD1 protein production. It is administered intrathecally as three loading doses at 14-day intervals, followed by maintenance doses every 28 days. Biogen licensed tofersen from Ionis Pharmaceuticals, Inc.
In addition to the ongoing OLE of VALOR, QALSODY is being studied in the Phase 3, randomized, placebo-controlled ATLAS study (NCT04856982) to evaluate whether it can delay clinical onset of ALS when initiated in presymptomatic individuals with a SOD1 genetic mutation and biomarker evidence of disease activity.
Amyotrophic lateral sclerosis (ALS) is a rare, progressive and fatal neurodegenerative disease. SOD1-ALS is diagnosed in approximately 2 percent of all ALS cases, with about 330 people in the United States living with the disease.
Biogen has been committed to advancing ALS research for over a decade, including a robust discovery pipeline to address TDP43 pathology for the broad ALS population.
Madeleine Shin
+ 1 781 464 3260
public.affairs@biogen.com
Tim Power
+1 781 464 2442
IR@biogen.com
Source: Biogen
