Rheumatoid arthritis and alopecia areata appear to be two completely different diseases. One causes joint pain and swelling, while the other leads to severe hair loss. However, all two are autoimmune diseases. In the case of alopecia, the immune system begins to attack the hair follicles, while in that of arthritis, it attacks the tissues of the joints.
A new study in a phase 3 clinical trial has found that the treatments for these two diseases could be similar. Baricitinib, a drug treating arthritis, would be effective against alopecia areata in a third of patients.
The treatment owes its effectiveness to the presence of a protein called Janus kinase or JAKs. These enzymes are part of a signaling pathway called JAK-STAT, which occurs in the immune system. JAK inhibitors such as baricitinib may dampen this immune response in some patients, and to permit the presence of repels.
Double-blind, randomized, placebo-controlled trials cananalyze the efficacy of baricitinib in people with severe alopecia. The researchers divided 1,200 patients into three groups. Participants received either a placebo, 2 mg baricitinib, or 4 mg baricitinib for 36 weeks. The best result goes to those who received 4mg baricitinib. The hair of more than a third of them has grown significantly.
A tool called SALT (Severity of Alopecia Tool) was used to assess the effectiveness of the drug. The score ranges from 0 (no hair loss) to 100 (complete hair loss). At the start of the trial, all participants had a score greater than 50. At the end of the trial, approximately 35% of patients on 4 mg baricitinib and 20% receiving 2 mg baricitinib had a score of 20 or less (primary outcome). According to the team, most patients in whom the primary outcome was achieved had a SALT score of 10 or less at week 36.
Side effects in some participants
The researchers reported side effects in some groups. Since the drug acts on the immune system, it may reduce its ability to defend the body against real threats. An increase in infections among people using arthritis medications had previously been observed.
However, few participants dropped out due to side effects. This suggests that they were globally tolerable. Further research is currently underway to confirm long-term safety and effectiveness. In any case, the result is encouraging.
We may soon see this medication marketed to also treat alopecia areata.
“These large controlled trials tell us that we can alleviate some of the suffering associated with this terrible disease. »
Brett King, dermatology researcher at Yale