FDA extends review period for Biogen/Ionis ALS therapy tofersen
Iryna Drozd

The U.S. Food and Drug Administration (FDA) extended the review period for Biogen (NASDAQ:BIIB) and Ionis' (NASDAQ:IONS) amyotrophic lateral sclerosis (ALS) therapy tofersen by three months to April 25, 2023.
In July, the FDA had accepted the company's new drug application (NDA) application and granted priority review to tofersen to treat patients with superoxide dismutase 1 (SOD1) ALS. The FDA was expected to make a decision by by Jan. 25, 2023.
Biogen on Monday said that it submitted responses to information requested by the FDA under the review, which the U.S. drug regulator considered a major amendment to the application and thus will require more time for review.
"We are committed to providing any details the agency needs to complete the review of tofersen,â said Priya Singhal, head of Global Safety and Regulatory Sciences and interim head of R&D at Biogen.
Singhal added that as the review continues, Biogen will maintain the early access program for tofersen.
In June, Biogen reported 12-month data from the phase 3 VALOR study of tofersen
ALS is a progressive nervous system disorder affecting nerve cells in the brain and spinal cord, leading to loss of muscle control. SOD1 ALS is caused due to mutations in the SOD1 gene.
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