Assessing the Combination of Oral Baricitinib and UV-B Phototherapy in Managing Vitiligo
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Reviewed by Dat Tien Nguyen, B.A, ScM.
Translated by Nhi Phuong Quynh Le, B.A |
Posted on February 17th, 2025
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Vitiligo is an autoimmune disorder in which CD8-positive T-cells attack the pigment-producing melanocytes in the epidermis, resulting in patches of milky-white skin. This process is influenced by interferon-gamma and interleukin-13, and can be managed using therapies that target the Janus kinase (JAK) proteins involved in signal transduction. A study funded by Eli Lilly investigated the potential benefits of combining oral baricitinib, a JAK inhibitor, with UV-B phototherapy for vitiligo management.
The phase 2 clinical trial was performed in France, with the participation of 49 individuals between the age of 18 and 75, who had been diagnosed with vitiligo that had affected more than 5% of the body surface area, excluding the feet and hands. Baseline assessment with the Vitiligo Area Scoring Index yielding an average total and facial score of 16 and 0.4, respectively - the scale has a maximum score of 100, which represents the most severe form of disease.
The participants were randomly assigned to be treated with either placebo or baricitinib orally, at a daily dose of 4 mg. After 12 weeks, all of the participants were subjected to narrow band UV-B phototherapy targeting the affected skin area. Baricitinib works by blocking the JAK1/JAK2 protein from transducing the signal produced by the receptor for interferon gamma and interleukin 13, which hamper the activation and survival of autoimmune CD8 T-cells. Additionally, UV-B counteracts the depigmentation of vitiligo by promoting the proliferation and differentiation of melanocytes.
After 36 weeks of treatment, the researchers noted that patients treated with baricitinib experienced an average 44.8% reduction in the VASI score, significantly more than the 9.2% in the placebo group. The usage of baricitinib with UV-B phototherapy did not increase the risk of secondary infection or other adverse events, which is consistent with the safety profile reported in study that assessed the usage of baricitinib in atopic dermatitis and alopecia areata. However, due to its small sample size, the study effect had significant variation, and its design was not compatible with the investigation of skin repigmentation.
The phase 2 clinical trial was performed in France, with the participation of 49 individuals between the age of 18 and 75, who had been diagnosed with vitiligo that had affected more than 5% of the body surface area, excluding the feet and hands. Baseline assessment with the Vitiligo Area Scoring Index yielding an average total and facial score of 16 and 0.4, respectively - the scale has a maximum score of 100, which represents the most severe form of disease.
The participants were randomly assigned to be treated with either placebo or baricitinib orally, at a daily dose of 4 mg. After 12 weeks, all of the participants were subjected to narrow band UV-B phototherapy targeting the affected skin area. Baricitinib works by blocking the JAK1/JAK2 protein from transducing the signal produced by the receptor for interferon gamma and interleukin 13, which hamper the activation and survival of autoimmune CD8 T-cells. Additionally, UV-B counteracts the depigmentation of vitiligo by promoting the proliferation and differentiation of melanocytes.
After 36 weeks of treatment, the researchers noted that patients treated with baricitinib experienced an average 44.8% reduction in the VASI score, significantly more than the 9.2% in the placebo group. The usage of baricitinib with UV-B phototherapy did not increase the risk of secondary infection or other adverse events, which is consistent with the safety profile reported in study that assessed the usage of baricitinib in atopic dermatitis and alopecia areata. However, due to its small sample size, the study effect had significant variation, and its design was not compatible with the investigation of skin repigmentation.