The following is the summary of “Effectiveness of Hydroxychloroquine and Omalizumab in Chronic Spontaneous Urticaria: A Real-World Study” published in the December 2022 issue of Allergy and Clinical Immunology by Khan, Et al.

When antihistamines cannot treat chronic spontaneous urticaria (CSU) at optimal levels, we call it refractory CSU. Guidelines recommend omalizumab, immunosuppressive, and anti-inflammatory medicines as further therapy. The study aimed to evaluate the efficacy of supplementary therapies for refractory CSU in 2 large clinical settings. Retrospective case reviews were performed on 264 patients with refractory CSU who had not been satisfactorily managed for 6 weeks on optimal doses of second-generation histamine-1 blockers. 

Clinical results might be compared between the 2 most commonly given add-on medications, omalizumab, and hydroxychloroquine. Both the disappearance of or considerable reduction in urticaria and the patient’s happiness with the treatment constituted a complete response. Hives improved somewhat, but only after a second treatment was added. A complete response to supplemental treatment that lasts more than a year is considered to have a sustained response. Complete remission was substantially more common in patients treated with omalizumab as an adjunct to hydroxychloroquine. 1-year post-treatment, 82% (111 of 134) of omalizumab patients and 66% (73 of 111) of hydroxychloroquine patients had a complete, sustained response (P<.01). 

Comparing patients without thyroid disease to those with it, those with thyroid disease responded less favorably to supplementary treatments (45% vs. 63%; P=.03). Completion rates for omalizumab and hydroxychloroquine were 65% and 62%, respectively, among patients who had partial responses to initial add-on therapies (n=45). Two-thirds of individuals treated with hydroxychloroquine had a complete response, while omalizumab only managed a partial response. Hydroxychloroquine has a good safety profile and could be used as an adjunct treatment for CSU that has not responded to other methods.