Biogen’s quest to develop additional medicines for Alzheimer’s disease beyond the company’s newly approved aducanumab hit a clinical snag as the anti-tau antibody gosuranemab failed to meet endpoints in a Phase II study and was discontinued.

Switzerland-based AC Immune SA announced positive interim results from the company’s ongoing Phase Ib/IIa clinical trial of ACI-35.030 for Alzheimer’s disease.

Biogen is discontinuing development of an experimental therapy for a rare brain disease after the treatment failed a mid-stage trial, the latest setback in attempts to develop a medicine for the disorder.