(Reuters) - (This Sept. 25 story has been corrected to remove reference to accelerated approval for Amylyx's ALS drug in paragraph 7)
The U.S. Food and Drug Administration's staff reviewers raised concerns on Monday over the safety and efficacy of BrainStorm Cell Therapeutics' therapy for a rare and fatal neurodegenerative disease called amyotrophic lateral sclerosis (ALS).
The company's shares were down nearly 40.4% to 49 cents in early trading.
Brainstrom's therapy, NurOwn, is being reviewed for the treatment of ALS, also known as Lou Gehrig's Disease, which affects nerve cells in the brain and spinal cord.
The FDA, in its briefing documents, said it does not believe there is sufficient evidence to support NurOwn's clinical benefit, adding there were large amounts of missing data.
The health regulator also identified a higher incidence of deaths in the treatment group and said it indicates a lack of survival benefit and warrants further investigation.
The FDA had in November last year refused to accept the application for the therapy after BrainStorm failed to meet the main goal in a late-stage study. The company still went ahead and made the submission in protest.
Over the last one year, the FDA has green-lighted Amylyx Pharmaceuticals' drug Relyvrio and given accelerated approval for Biogen's Qalsody for treatment of ALS. Amylyx's approval process was especially long-drawn due to concerns over its data.However, Amylyx had the support of the ALS Association, but the group has refused to take a position for or against BrainStorm's therapy despite being the largest patient advocacy funder for the treatment, with a total investment of $500,000, due to concerns over its data.
"The amazing testimonials we have seen online do not align with the data that BrainStorm has shared with us or has been published in peer-reviewed publications," the Association had said on its website.
A panel of external advisors to the FDA is set to vote on the effectiveness of the therapy in ALS patients on Wednesday.
(Reporting by Mariam Sunny and Leroy Leo in Bengaluru; Editing by Krishna Chandra Eluri)