This month's Phase II data neither proved nor disproved AC Immune S.A.'s hypothesis that it could dial out enough toxicity in crenezumab to enable a higher, more efficacious dose for AD than previous anti-beta amyloid mAbs. The reason is that dosing was limited by an entirely different issue - low manufacturing yields.

Partner Genentech Inc. believes it may now be possible to achieve a higher dose, although neither company would discuss next steps for the program.