A multicenter, double-blind, randomized, noninferiority comparison of 14 days' treatment with oral olopatadine 10 mg or cetirizine 10 mg in Chinese adults with cutaneous pruritus.

To assess whether olopatadine hydrochloride (OH) was noninferior to cetirizine in the treatment of cutaneous pruritus (CP). Patients with CP presenting at seven centers in China were randomly allocated to double-blind treatment with 5 mg of OH orally twice a day or cetirizine 10 mg orally once a day for 2 weeks. Patients were followed up on days 7 and 14. Noninferiority was predefined as a 20% maximum difference in the reduction of symptom score reducing indices (SSRI). Both intention-to-treat (ITT) and per-protocol populations were analyzed. 174 patients (86 receiving OH and 88 cetirizine) were included in the ITT population. In the ITT population, the mean reduction in SSRI was 0.640 ± 0.274 in the OH group and 0.603 ± 0.289 in the cetirizine group. The one-sided 97.5% CI (-0.047) met the criteria for noninferiority. Noninferiority was also demonstrated for SSRI in the per-protocol population, with reductions of 0.640 ± 0.271 with OH and 0.596 ± 0.287 with cetirizine (97.5% CI -0.043).The total effectiveness rate (TER) was similar in the OH (90.0%) and cetirizine (80.0%) groups. The corresponding one-sided 97.5% CI (-1.0%) also demonstrated noninferiority. The incidence of adverse events was 47.1% in the OH group and 41.4% in the cetirizine group (p = 0.453). The efficacy of OH was noninferior to that of cetirizine in controlling itching indicating that it can be considered as a clinically relevant alternative therapy to cetirizine for the management of CP in adult Chinese patients.