Evaluating efficacy and safety: The RAAINBOW study
Dr. Blume-Peytavi acknowledged that JAK inhibitors were “a tremendous advance in treating severe and very severe alopecia areata,” but because of their benefit-to-risk ratio, there was still an unmet need for new treatments, particularly in children, in whom drug safety is of critical importance.
Having a drug that could be given safely and also have an effect early on in the disease, while it is still at a mild to moderate stage, would be of considerable value, Dr. Blume-Peytavi maintained.
The RAAINBOW study was a randomized, double-blind, phase 2/3 trial conducted at 12 sites in Germany and three other countries between March 2018 and March 2022 to evaluate the efficacy and safety of coacillium in the treatment of children and adolescents with moderate to severe alopecia areata.
In all, 62 children aged 2-18 years (mean age, 11 years) participated; 42 were treated twice daily with coacillium cutaneous solution 22.5% and 20 received placebo for 24 weeks. Treatment was then stopped, and participants followed for another 24 weeks off treatment to check for disease relapse, bringing the total study duration up to 48 weeks.
Baseline characteristics were “relatively comparable for severity,” Dr. Blume-Peytavi said. Most of the children had severe alopecia areata (57% for coacillium and 65% for placebo); the remainder had moderate disease (43% vs. 35%, respectively).
The average SALT scores at the start of treatment were 56 in the coacillium group and 62 in the placebo group, and a respective 44 and 61 at the end of 24 weeks’ treatment.
Perhaps the most important results, Dr. Blume-Peytavi said, was that at 48 weeks of follow-up, which was 24 weeks after treatment had been discontinued, the mean SALT scores were 29 for coacillium and 56 for placebo (P < .0001).
“You can see the improvement in the treated group is continuing even without treatment. However, the placebo group stays relatively about the same range,” she said.
Overall, 82% of patients treated with coacillium and 37% of those who received placebo experienced hair growth after treatment had stopped, and by week 48, a respective 46.7% vs. 9.1% had a SALT score of 20 or less, and 30.0% vs. 0% had a SALT score of 10 or less.
No safety concerns were raised, with no serious treatment-related reactions, no immunosuppressant-like reactions, and no steroidlike side effects.
Beyond the RAAINBOW
Larger studies are needed, Dr. Blume-Peytavi said. According to developer Legacy Healthcare’s website, coacillium cutaneous solution is not being developed just for childhood alopecia areata. It is also under investigation as a treatment for persistent chemotherapy-induced alopecia, atopic dermatitis, and psoriasis. In addition, an oral solution is being tested for cancer-related fatigue.
The study was funded by Legacy Healthcare. Dr. Blume-Peytavi has received research funding and acts as an advisor to the company, among others; four of the study’s coauthors are employees of the company. Dr. Pasquali and Dr. Guttman-Yassky were not involved in the study and had no relevant financial ties to disclose.
A version of this article first appeared on Medscape.com.