Ms. Vear wants to try her father on bexarotene, though she does have concerns about possible side effects.

WSJ: Alzheimer's Families Clamor for Drug

Patents on bexarotene will start to expire this year, and once a generic is available, doctors could prescribe that less-expensive version off-label, undercutting the commercial prospects.

WSJ: Alzheimer's Families Clamor for Drug

In February, when results in mice were published suggesting that a skin-cancer drug, bexarotene, was beneficial for Alzheimer's, many patients or their families started calling their doctors to ask whether they should use it off-label.

WSJ: Immune-Disorder Drug Shows Promise for Alzheimer's