Tofersen: A Review in Amyotrophic Lateral Sclerosis Associated with SOD1 Mutations

Declarations

Funding The preparation of this review was not supported by any external funding.

Authorship and Conflict of interest Aisling McGuigan and Hannah A. Blair are salaried employees of Adis International Ltd/Springer Nature, and declare no relevant conflicts of interest. All authors contributed to this article and are responsible for its content.

Ethics approval, Consent to participate, Consent to publish, Availability of data and material, Code availability Not applicable.

Additional information about this Adis Drug Review can be found here.

Abstract

Tofersen (QALSODY^®) is the first drug approved for the treatment of amyotrophic lateral sclerosis (ALS) associated with superoxide dismutase 1 (SOD1) mutations. Tofersen is an antisense oligonucleotide that induces SOD1 mRNA degradation. In the 28-week, placebo-controlled, multinational, phase III VALOR trial, intrathecally administered tofersen reduced plasma concentrations of neurofilament proteins (biomarker for neuro-axonal injury) and total SOD1 protein in cerebrospinal fluid in patients with SOD1 mutation-associated ALS. These reductions were sustained in a long-term, open-label extension study. The decline in functional outcomes was not significantly reduced with tofersen treatment compared with placebo in the 28-week phase III trial, although in the longer-term open-label study, early tofersen initiation was associated with slowed functional decline versus delayed tofersen initiation. Tofersen had an acceptable tolerability profile in clinical trials with a favourable benefit-to-risk balance. In summary, tofersen is a new disease-modifying therapy for patients with ALS attributed to an SOD1 mutation, offering reductions in levels of a biomarker associated with neurodegeneration and disease progression, with an acceptable tolerability profile.

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