A drug already used in the treatment of rheumatoid arthritis and other autoimmune diseases has proven effective in combating alopecia areata, stimulating hair regrowth in patients affected by the most severe forms of the disease, who until now lacked effective therapeutic options. This is upadacitinib, an active ingredient belonging to the class of Janus kinase (Jak) inhibitors: the results of two large international clinical studies, just published in the journal Jama Dermatologyreveal that the daily oral administration of this molecule allowed over half of the patients treated with the highest dosage to recover almost all of their hair within twenty-four weeks.
Clinical trials
Alopecia areata is an autoimmune disease in which the immune system mistakenly attacks the hair follicles, causing hair and body hair to fall out, either partially (causing characteristic hairless patches) or, in the most severe cases, completely. It affects approximately one in 50 people, with over 160 million patients estimated worldwide.
Upadacitinib is a drug developed for the treatment of another autoimmune disease, rheumatoid arthritis, and works by blocking specific enzymes, Janus kinases, involved in inflammatory signaling pathways. For this reason, it was decided to test the drug also in patients with alopecia areata, to verify whether its mechanism of action could also stop the autoimmune responses directed against the hair follicles.
The two phase 3 clinical trials, called UP-AA1 and UP-AA2, involved a total of 1,399 participants aged between 12 and 64, all suffering from severe forms of alopecia areata with hair loss equal to or greater than 50 percent of the scalp. The volunteers were randomly divided into three treatment groups: the first was administered a daily dose of 15 milligrams of active ingredient, the second a dose of 30 milligrams and the third a placebo.
The results
The data that emerged at the end of twenty-four weeks of observation indicate excellent efficacy in the groups treated with Jak inhibitor. In the 15-milligram dose group, nearly half of patients achieved regrowth of at least 80 percent of scalp coverage, with more than a third of subjects exceeding the 90 percent threshold.
With the higher dose, the share of patients who recovered at least 80 percent of their hair rose to more than 54 percent. In this group, a significant regrowth of eyebrows and eyelashes was also observed. In the placebo control group, however, only about 2 percent of participants showed comparable improvements. The first visible signs of regrowth appeared already around the eighth week of treatment.
A possible therapeutic revolution
The safety profile that emerged from the trials reflects that already known for the class of Jak inhibitors. The most commonly reported adverse events among participants were acne, upper respiratory tract infections and mild flu symptoms, with no new unexpected issues emerging.
Since it is a therapy with immunomodulatory action, administration still requires a clinical evaluation of the relationship between risks and benefits for the individual. However, the results represent a potential revolution for patients with severe alopecia areata, currently without real therapeutic options and suffering from a disease that profoundly impacts psychological well-being and quality of life.