The Food and Drug Administration issued guidance in February for clinical trials for early-stage Alzheimer’s medications.

The agency said in February it would not accept biomarker outcomes as a primary endpoint in trials for Alzheimer’s disease medications. 

It noted a lack of “widespread evidence-based agreement in the research community that an effect on a particular biomarker is reasonably likely to predict clinical benefit.” However, the FDA may consider biomarker levels as a secondary outcome measure, with a primary clinical change.