An experimental Alzheimer’s disease drug from Biogen Inc. and Eisai Co. slowed the progression of the earliest stages of the devastating condition by 30% in a study, a first in the decades-long research that has thus far been littered with failures.
Doctors and patient advocates said the results were encouraging, though more information was needed from larger, longer studies before any real promise from the drug could be accurately measured.
Only the highest of the five doses worked. And while the percentage benefit exceeded analysts’ expectations, the new data was for patients treated for 18 months rather than the 12 months many had anticipated — which muddled comparisons. Investors may have hoped for a fuller success. Biogen fell 10% in late trading Wednesday after closing at the highest in three years ahead of the data presentation.
The trial itself has been shrouded in secrecy. After an initial analysis using a novel approach failed to find a significant improvement in December, the companies announced three weeks ago that a different approach yielded positive results.
“It’s encouraging, but a lot more needs to be done,” said Julie Schneider, associate director of Rush Alzheimer’s Disease Center in Chicago, and one of the few outside experts who had seen the latest data released Wednesday. “I would not say it’s shock and awe.”
The results for the drug, called BAN2401, were presented at the Alzheimer’s Association International Conference in Chicago. Shares of both Biogen, based in Cambridge, Massachusetts, and Japan’s Eisai had soared earlier this month after the companies presented the initial positive results.