Read More Pharma Industry News Biogen stock (NASDAQ: BIIB) falls 8.2%: Can diranersen recover in Phase 3? Biogen’s diranersen reduced tau and showed its strongest clinical result at the lowest dose, but the Phase 2 study missed its dose-response goal. With $BIIB down 8.2%, July 29 results and the Phase 3 design become the next tests. bySrinathJuly 15, 2026