Biogen shares fell as the company flagged a $46 million Q2 charge tied to R&D deals, reducing EPS by $0.26. The update follows FDA concerns over the Alzheimer's drug Leqembi. RBC analysts expect no significant fallout but warn of a sentiment overhang. Biogen is also advancing felzartamab into Phase 3 trials. The stock is down 13.3% YTD.