Alzheimer’s drug manufacturers are asking the FDA to give them more clarity on the different stages of the disease in comments they’ve submitted on the agency’s draft guidance for developing drugs for early Alzheimer’s disease.
The FDA in March updated its guidance on research and development for drugs treating early Alzheimer’s disease, which featured several major changes compared to the previous version that was last updated back in 2018. The latest version includes a new section on surrogate endpoints and accelerated approval.
The updated guidance also includes a section on amyloid, an abnormal protein that is targeted by Biogen and Eisai’s already-approved lecanemab and Eli Lilly’s donanemab, which is awaiting approval after an advisory committee backed the drug at a meeting earlier this week.
Lilly recommended several updates in its comments regarding the FDA’s interpretation of the stages of early Alzheimer’s disease, including clarifying the impact of mild cognitive symptoms in stage 2 of the disease. The Indianapolis-based company also asked the FDA to recognize that stage 2 could be a transition stage in which mild symptoms appear.
Lilly is also asking the FDA to either expand the scope of the guidance to include later-stage Alzheimer’s disease, or draft a separate guidance for those stages.
Biogen, which manufactures lecanemab alongside Eisai, said it would like the FDA to update the guidance to differentiate between asymptomatic and pre-mild cognitive impaired patients with biomarkers from those with symptomatic early Alzheimer’s. The company also said it supports the inclusion of guidance on surrogate endpoints in drug development for early Alzheimer’s.
“Additional details about the use of biomarkers of common Alzheimer’s disease interest (e.g. tau, amyloid) in different Alzheimer’s disease stages in a clinical development program would be informative for future guidance,” Biogen wrote.
Eisai requested that the FDA clarify the symptoms for stages 2 and 3 of the disease, noting that the neuropsychological and functional measures of the disease don’t evolve at the same pace.
Eisai also asked for more clarity on the FDA’s definition of mild cognitive impairment, which it focuses on in its interpretation of stage 3 Alzheimer’s.