FDA grants accelerated approval for drug to treat rare form of ALS

April 25 (UPI) -- Regulators with the Food and Drug Administration on Tuesday signed off on accelerated approval for Biogen's tofersen injection to treat those who suffer from a rare form of the progressive neurodegenerative disease amyotrophic lateral sclerosis, better known as ALS.

The drug, which will be sold under the brand name Qalsody, is administered to patients as three 100-mg. spinal injections at 14-day intervals, followed by a maintenance dose every 28 days after.

The treatment is for ALS in adults who have a mutation in the superoxide dismutase 1 gene, which is a form of the deadly disease that affects about 2% of the 16,000 to 32,000 Americans with ALS, according to the FDA.

It was approved under the FDA's accelerated approval program, which seeks to rapidly make available drugs that treat serious conditions in which unmet medical needs exist.

According to the regulators, tofersen was given approval after it showed in a 28-week trial to have reduced levels of NfL, a protein that neurons release when they are damaged, indicating neurodegeneration.

"The findings are reasonably likely to predict a clinical benefit in patients," the FDA said in its announcement. "The observed reduction in NfL was consistent across all subgroups based on sex, disease duration since symptom onset, site of onset and use of other medications for ALS treatment."

According to Biogen, tofersen is the first approved treatment targeting a genetic cause of ALS.

"For more than a decade, Biogen has been steadfast in our commitment to pursuing treatments for ALS, and I want to thank the scientists as well as the entire ALS community who have all worked tirelessly to bring this first-of-its-kind treatment to people with SOD1-ALS," Christopher Vienhacher, president and chief executive officer of Biogen, said in a statement.

"Today also marks a pivotal moment in ALS research as we gained, for the first time, consensus that neurofilament can be used as a surrogate marker reasonably likely to predict clinical benefit in SOD1-ALS. We believe this important scientific advancement will further accelerate innovative drug development for ALS."

Also known as Lou Gehrig's disease, ALS affects motor neurons that control voluntary muscle movement, such as chewing and walking, and is a progressive disease that has no cure and no effective treatment to reverse degeneration, according to the National Institute of Neurological Disorders and Stroke.