New Alzheimer's drug faces uncertain regulatory path

Researchers have at last found a drug that can slow the progression of Alzheimer's disease, according to clinical trial data presented last night. But regulators now have to weigh its relatively modest efficacy against safety risks.

What we're watching: The FDA will soon decide whether to approve Eisai's experimental drug lecanemab — and if so, for the general public or only certain patient populations.

Medicare will then have to decide whether to pay for it outside of clinical trials or to maintain restrictions it put in place when it considered a...