The FDA has quietly rewritten the rulebook for Alzheimer's treatment, approving at-home use of lecanemab (Leqembi) from day one — no more mandatory 18 months of IV infusions before patients can switch to subcutaneous injections. The move, reported by The BMJ, dramatically expands access to the only disease-modifying Alzheimer's drug on the market and could reshape treatment costs globally.

Vital Signs

Key numbers driving the story:

• 18 months — the previous...