Corium has nabbed an FDA approval for Adlarity, a once-a-week transdermal donepezil patch intended for patients with mild, moderate or severe Alzheimer’s disease.

The approval is the first nonoral formulation of the 26-year-old workhorse Alzheimer’s drug, first marketed by Pfizer as Aricept.

Donepezil stabilizes, and sometimes improves, memory and thinking for a short period in people with early- to mid-stage disease. It doesn’t change the course of the disease and is prescribed only symptomatically. But it’s notorious for causing stomach problems, and many patients develop nausea and diarrhea that causes them to ultimately discontinue therapy.

Transdermal delivery systems avoid this problem by sending the drug directly into the bloodstream, sidestepping gastrointestinal exposure. Transdermal dosing also contributes to steady-state drug levels - an important factor for patients who can sometimes have trouble swallowing pills.

Adlarity will debut on the market next fall. The patch will be available in formulations dispensing 5 mg or 10 mg each day.