Researchers have identified the immune cells responsible for destroying hair follicles in people with alopecia areata, a common autoimmune disease that causes hair loss, and have tested an FDA-approved drug that eliminated these immune cells and restored hair growth in a small number of patients.
In the paper, the researchers report initial results from an ongoing clinical trial of the drug, which has produced complete hair regrowth in several patients with moderate-to-severe alopecia areata. Data from three participants appear in the current paper; each patient experienced total hair regrowth within five months of the start of treatment.
“We’ve only begun testing the drug in patients, but if the drug continues to be successful and safe, it will have a dramatic positive impact on the lives of people with this disease,” said Raphael Clynes, MD, PhD, who led the research, along with Angela M. Christiano, PhD, professor in the Departments of Dermatology and of Genetics and Development at CUMC.
The current paper describes how the team first studied mice with the disease, then tracked backward from the danger signal to identify the specific set of T cells responsible for attacking the hair follicles. Further investigation of mouse and patient cells revealed how the T cells are instructed to attack and identified several key immune pathways that could be targeted by a new class of drugs, known as JAK inhibitors.
Two FDA-approved JAK inhibitors tested separately by the researchers—ruxolitinib and tofacitinib—were able to block these immune pathways and stop the attack on the hair follicles. In mice with extensive hair loss from the disease, both drugs completely restored the animals’ hair within 12 weeks. Each drug’s effect was also long-lasting, as the new hair persisted for several months after stopping treatment.
“We still need to do more testing to establish that ruxolitinib should be used in alopecia areata, but this is exciting news for patients and their physicians,” Dr. Clynes said.
Source: Columbia University Medical Center, USA