Biogen Inc’s keenly watched experimental drug for treating multiple sclerosis, a nervous system disease affecting the brain and the spinal cord, did not meet the main goal of improving some symptoms in a mid-stage study.
The company’s shares fell as much as 9 percent to $263.59 in premarket trading on Tuesday.
The drug, opicinumab, did not improve overall physical and cognitive function and the progression of disability in patients, the company said.
Analysts have previously said the drug represented a multi-billion opportunity for Biogen given its potential to repair nerve damage caused by multiple sclerosis.
“We think opicinumab — if ultimately successful — would be broadly used in the MS space in all stages of disease,” J.P. Morgan analysts wrote in a note last week.
Biogen has been focusing on developing its drug pipeline after demand for its key MS drug, Tecfidera, stalled in recent quarters.
The study, which enrolled 418 patients, was the second mid-stage trial testing opicinumab.
Biogen said the drug showed evidence of a clinical effect in patients, and would continue to analyze the data to decide on the design of the next study.
The first study was designed to evaluate the effect of opicinumab following a first episode of acute optic neuritis, or inflammation of the optic nerve.
(Reporting by Amrutha Penumudi in Bengaluru; Editing by Saumyadeb Chakrabarty)