Biogen’s ALS drug shows symptom improvement in some patients three years after approval

Biogen’s antisense therapy tofersen, marketed as Qalsody, received FDA approval three years ago as the first treatment to target a genetic form of ALS linked to the SOD1 gene.

Since then, a number of patients have reported not only a halt in disease progression but also measurable gains in function, suggesting the drug may reverse some aspects of the condition.

One patient, Paula Trefiak, a former ballet dancer, entered an early trial of the drug in 2016. After an initial low dose failed to stop her decline, she stopped treatment and her symptoms worsened, highlighting the challenges of dosing.

The emerging positive reports are prompting clinicians to consider broader use of the therapy for eligible ALS patients, though further data are needed to confirm the extent of benefit.