Narrow Band Ultraviolet B Phototherapy Effective as Alternative to Cyclosporine for CSU

Narrow Band Ultraviolet B (NB-UVB) phototherapy is an effective and well-tolerated alternative to cyclosporine for antihistamine-refractory chronic spontaneous urticaria (CSU), according to new findings.1

Such conclusions on NB-UVB phototherapy were the result of a recent study conducting with the aim of comparing the NB-UVB phototherapy’s safety and efficacy compared to cyclosporine in antihistamine-refractory CSU. The data were authored by such investigators as Muthu Sendhil Kumaran, MD, from the Department of Dermatology, Venereology, and Leprology at the Post Graduate Institute of Medical Education and Research in India.

Kumaran and colleagues highlighted the efficacy of NB-UVB has been proven by itself or with antihistamines in individuals who have not responded to standard therapies. The treatment option has been shown to outperform other treatments such as PUVA, but there had been a lack of prior research comparing cyclosporine and NB-UVB directly.2

“In this context, we conducted a randomized, prospective, non-inferiority study comparing NB-UVB phototherapy with low-dose oral cyclosporine in 50 patients of oral anti-histamine refractory CSU,” the investigators wrote.1 “By characterizing the treatment responses to each modality, we seek to provide insights into their relative efficacy and safety, guiding clinicians in optimizing patient care.”

Study Design and Notable Findings

The investigative team involved 50 individuals as trial subjects in their randomized, prospective non-inferiority study. The study specifically looked at patients with CSU who also did not respond to antihistamines. Screening of these individuals was conducted by Kumaran et al consecutively, and patients deemed eligible were recruited after the investigators received informed consent.

Criteria for inclusion in this study required participants to specifically report having active CSU characterized by daily or near-daily wheals and pruritus, with or without angioedema, for more than 6 months. They were also required to have been refractory to up to a fourfold increase in second-generation antihistamines for 3 months at minimum. These subjects were then randomized to be given either narrowband UVB (NB-UVB) on a 3 times per week basis or cyclosporine 3 mg/kg/day for a total of 90 days, in combination with maximally regulated doses of antihistamines. This would be followed by a 90-day observation period.

Among the 526 individuals Kumaran and coauthors screened, 152 were found to have met the investigators' eligibility criteria. Among these, 71 were excluded and 31 declined enrollment, resulting in 50 patients being randomized into the treatment arms. The study's primary endpoint was the 7-day Urticaria Activity Score (UAS7). Additional outcomes evaluated by the investigative team included the Chronic Urticaria Quality of Life (CU-QoL) questionnaire, the Urticaria Control Test (UCT), and biomarker evaluations (IL-6 and IL-31).

Overall, the team found that both of these interventions produced a significant reduction in UAS7 scores by the 15-day mark. They identified an association between NB-UVB and durable symptom control following treatment cessation. This was compared to cyclosporine, which led to rapid improvements among participants but was followed by rebound exacerbations once it was discontinued.

Kumaran and colleagues' non-inferiority analysis confirmed that NB-UVB was not significantly less effective than treatment with cyclosporine in the reduction of UAS7. Both of these options lowered trial participants' serum IgE levels, while IL-6 and IL-31 demonstrated significant reductions only in the cyclosporine arm of the study. In short, NB-UVB showed efficacy and tolerability as an alternative to cyclosporine for those living with antihistamine-refractory CSU. The treatment provided prolonged suppression of disease activity following treatment. Additional studies may be warranted to look at long-term outcomes and the data's generalizability.

“Cyclosporine exhibited a crisis-buster effect with swift disease control, while NB-UVB showcased sustained disease activity suppression even post-intervention,” they wrote.1 “The study underscores NB-UVB's invaluable role as a viable alternative to cyclosporine, offering a well-tolerated, effective, and potentially long-term therapeutic option for the management of CSU.”

References

1. N Roshini, H Mehta, A Bishnoi, et al. Narrow Band Ultraviolet B Phototherapy Versus Oral Cyclosporine in the Treatment of Chronic Urticaria. Photodermatology, Photoimmunology & Photomedicine 41, no. 5 (2025): e70050, https://doi.org/10.1111/phpp.70050.

2. Sheikh G, Latif I, Keen A, et al. Role of Adjuvant Narrow Band Ultraviolet B Phototherapy in the Treatment of Chronic Urticaria. Indian J Dermatol. 2019 May-Jun;64(3):250. doi: 10.4103/ijd.IJD_475_16. PMID: 31148870; PMCID: PMC6537687.