FDA Committee Recommends Accelerated Approval of Tofersen

The Food and Drug Administration (FDA) held a virtual meeting of the Peripheral and Central Nervous System Drugs Advisory Committee on March 22, 2023, to review data supporting tofersen’s New Drug Application. Biogen is seeking approval of tofersen through the FDA’s Accelerated Approval Program.

Tofersen is an antisense oligonucleotide (ASO) being evaluated as a treatment for SOD1-ALS which is a rare genetic form of the disease affecting approximately 330 people in the United States. While there are medications approved for broad ALS, no available treatments target a genetic mutation associated with ALS. Approximately 5-10 percent of people with ALS are thought to have a genetic form of the disease, however, they may not have a known family history of the disease.

The FDA Peripheral and Central Nervous System Drugs Advisory Committee voted 9-0 that a reduction in plasma neurofilament light (NfL) concentration is “reasonably likely” to predict the clinical benefit of tofersen for the treatment of patients with SOD1-ALS. On a second question, the committee voted 5-3 (with one abstention) that the clinical data surrounding tofersen does not provide “convincing evidence” of the effectiveness of tofersen in the treatment of patients with SOD1-ALS. These votes support FDA approving tofersen under the accelerated approval pathway.

A decision is expected by April 25, 2023.