A new drug approved by the U.S. Food and Drug Administration (FDA) has been found to help restore hair growth in patients with alopecia areata.

Alopecia areata is an autoimmune disease in which the immune system mistakenly attacks hair follicles, causing hair loss.

Researchers at Columbia University Medical Center (CUMC) have discovered the immune cells that are responsible for destroying hair follicles in people with this common disease, which typically affects young people under the age of 20.

Lead study researcher Raphael Clynes, MD, PhD, along with Angela M. Christiano, PhD, professor in the Departments of Dermatology and of Genetics and Development at CUMC, reported results from a clinical trial of the new drug – ruxolitinib – which stimulated total hair regrowth in a number of patients suffering from moderate to severe alopecia areata. Each patient who experienced complete hair growth did so within five months of beginning the 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 Clynes in a statement.

The researchers say that more testing needs to be conducted to establish that ruxolitinib should be used to treat patients with alopecia areata, but this is encouraging news for patients and their doctors.

The results of the testing appear online in Nature Medicine.