Research into JAK inhibitors as a treatment for alopecia areata continues and we have now seen the first peer reviewed publication of a placebo controlled trial for the drug Baricitinib, showing response rates of over 50% achieving an improvement to less than 20% loss. Most patients entered into these trials had very severe alopecia. The entry criteria was to have at least 50% loss but most patients had much more than this with an average of around 80% loss in most trials. It is likely that patients with milder disease will respond better. These drugs seem to be very well tolerated. They have been associated with an increase in viral reactivation of both herpes simplex (cold sores) and varicella zoster (shingles).
The Pfizer trial of Ritlecitinib has yet to publish any interim results but you can read the press release on their progress. They have completed the one year study looking at different doses and the majority of those patients have continued into a longer term extension study. That study has now been extended from 2 to 3 years. They will be publishing safety data early in 2022 and we can expect to see a publication of the initial trial next year too.
None of these treatments have a license yet for Alopecia Areata and none are funded by the NHS. Baricitinib and Tofacitinib are available now and can be privately funded but the drug costs are high. You can read more about the use of JAK inhibitors here. JAK_inhibitors_alopecia