Carl Zimmer -- April 24, 2026
If approved by the PDUFA deadline roughly six months away, Eisai's drug, which slowed cognitive decline by 38 percent in Phase 3, could reach patients before year-end.
The Food and Drug Administration granted priority review designation on Thursday to Eisai's TREM2-targeting Alzheimer's drug candidate, setting a target decision timeline of approximately six months from the submission date.
Priority review status is granted to fewer than a quarter of new drug applications and reflects the FDA's assessment that the drug addresses a serious condition and may offer a substantial improvement over existing therapies. The PDUFA date, the agency's target deadline for a final decision, falls approximately six months from submission.
The drug targets TREM2, a protein that regulates the brain's immune cells. In a phase 3 trial enrolling 2,400 participants with early-stage Alzheimer's disease over 18 months, the drug slowed cognitive decline by 38 percent compared to placebo. The trial focused on patients at an early stage of disease, where intervention is considered most likely to produce meaningful benefit.
Eisai's shares rose 31 percent following the announcement. The company said it had begun discussions with payers and health systems regarding access pathways in preparation for a potential commercial launch.
The priority review designation does not guarantee approval. A final decision will follow the FDA's review of the full application within the six-month target window.