Upadacitinib shows hair regrowth in severe alopecia trials

At the start of two international trials, participants had lost about 84% of their scalp hair on average. Some had experienced no meaningful regrowth for at least six months. Within 24 weeks, roughly half of those taking upadacitinib reached at least 80% scalp coverage, while some reported complete or near-complete restoration.

The drug was tested once daily at 15 milligrams or 30 milligrams, with a placebo group for comparison. Hospitals and medical centers across North America, Europe and China took part, enrolling people with severe alopecia areata — an autoimmune disease in which the immune system attacks hair follicles and can also affect eyebrows and body hair.

Upadacitinib belongs to the JAK inhibitor class. These medicines block signals involved in the immune system’s inflammatory response; the researchers’ approach was to suppress the signals that may help drive the attack on hair follicles. The treatment is already used for rheumatoid arthritis and other inflammatory conditions, giving its possible use in alopecia areata an existing medical background.

And so what, concretely? For people with severe, persistent hair loss, the trial results suggest that substantial scalp coverage may be possible within months rather than years, even after extensive loss. The findings suggest that meaningful improvement can occur within months rather than requiring years, but they do not show that every patient will respond, or that regrowth will last.

The findings were published in JAMA Dermatology on August 12. Researchers caution that longer-term treatment and follow-up are still needed to measure durability and weigh the benefits against potential risks; the degree and speed of regrowth varied between patients.