Why a new Alzheimer's drug is having a slow US debut

The first drug to show that it slows Alzheimer’s is on sale, but treatment for most patients is still several months away.

Two big factors behind the slow debut, experts say, are scant insurance coverage and a long setup time needed by many health systems.

Patients who surmount those challenges will step to the head of the line for a drug that delivers an uncertain benefit. Here’s a closer look.

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