News from Biogen Inc. and partner Eisai Co. Ltd. that U.S. regulators accepted the BLA related to aducanumab for Alzheimer’s disease (AD) – and assigned it priority review, no less – set Wall Street abuzz, especially as the companies noted in their press release that the FDA “if possible, plans to act early” on the anti-amyloid beta (a-beta) monoclonal antibody. Regulators’ decision came about 30 days after they took receipt of the submission; they could have waited 60.