OBJECTIVES: Chronic spontaneous urticaria (CSU) is the sudden onset of hives and occasionally angioedema, lasting longer than six weeks. It is a condition that does not produce adequate treatment responses in >50% of patients prescribed H1-antihistamines. This review aimed to identify and categorize the outcomes and interventions used in clinical trials developing pharmaceutical therapies for effective treatment of CSU.

METHODS: A targeted search of the literature was conducted using ClinicalTrials.gov to collate trials assessing the efficacy of interventions addressing CSU. The Nested Knowledge AutoLit living review platform was used to identify and classify trial outcome measures, along with the drugs and comparisons used.

RESULTS: 53 clinical trials were included in this review. Sample size ranged from 10 to 1079 adults. The most frequent clinical outcome reported was the Weekly Urticaria Activity Score (UAS-7), which featured in 41 trials (77%). The next most frequently implemented clinical outcome, was the Urticaria Control Test (UCT), which was utilized in 6 trials (11%). Patient-reported outcome measures (PROMs) were included in 31 trials (59%). The most frequently used PROM was the Dermatology Life Quality Index (DLQI) (n=24/31; 77%) and the Chronic Urticaria Quality of Life questionnaire (CU-Q2oL) (n=9/31; 29%). Only six (11%) trials captured qualitative data via a patient diary.

Among 24 drugs used across the 53 trials, omalizumab was the most frequent (n=18 of trials; 34%), followed by desloratadine (n=5, 9%). Of the 53 trials, 34 (64%) used placebo comparisons, 7 (13%) used another drug and 12 (23%) used no placebo.

CONCLUSIONS: The evidence generated by this review suggests that the outcomes used to evaluate the impact of drug-based interventions on CSU are firmly established within the literature, while the range of drugs is considerably more diverse. The rarity of patient diaries indicates that future research could distinguish itself by capturing supplementary qualitative data.