Lilly’s apparent efficacy advantage in Alzheimer’s may not matter in practice

Investor reaction to Eli Lilly’s Alzheimer’s data suggests the market believes donanemab will be the amyloid therapy of choice, but that conclusion may be premature.

Donanemab only appears to have an efficacy advantage in patients with an “intermediate” level of tau deposition in the brain, as measured by PET imaging. Outside the context of a clinical trial, however, patients are unlikely to receive tau PET imaging. In the broader trial population, donanemab seemed to perform similarly to Leqembi lecanemab from  Eisai Co. Ltd. (Tokyo:4523) and Biogen Inc. (NASDAQ:BIIB) across a variety of endpoints...