Otsuka, Ionis' experimental ALS drug meets main goal in late-stage study

Ionis Pharmaceuticals

22/09/2026 13:36

Sept 22 (Reuters) - Otsuka Pharmaceutical and Ionis Pharmaceuticals IONS.O said on Tuesday their experimental drug met the main goal of a late-stage study in patients with a rare inherited form of amyotrophic lateral sclerosis, or ALS.
Here are more details:
Otsuka's ulefnersen improved function and survival compared with placebo in patients with FUS-ALS, a rare inherited form of the disease that damages nerve cells controlling movement.
There are currently no approved treatments specifically targeting the genetic cause of FUS-ALS.
The drug also reduced markers linked to nerve cell damage and delayed disease progression.
Most side effects were mild or moderate, and the companies said the drug showed a favorable safety profile.
Otsuka and Ionis plan to discuss the results with the US FDA and other health authorities globally as they pursue potential accelerated approval pathways.
FUS-ALS causes progressive muscle weakness that can leave patients unable to move, speak, swallow or breathe independently.
Otsuka's ulefnersen is an experimental medicine designed to reduce production of the FUS protein linked to the disease.
Separately, Otsuka launched a global early access program for eligible FUS-ALS patients who cannot participate in clinical trials, allowing physicians to request access to ulefnersen before any potential approval.

 (Reporting by Sahil Pandey in Bengaluru; Editing by Leroy Leo)
 ((Sahil.Pandey@thomsonreuters.com;))