Real-world clinical outcomes of tixagevimab/cilgavimab in the Omicron outbreak in China: baseline characteristics and interim analysis of the CLEAR study

Purpose: This study aimed to investigate the real-world use and clinical outcomes of tixagevimab/cilgavimab in China during the Omicron outbreak in late 2022.

Methods: This observational, real-world study included patients who received tixagevimab/cilgavimab from July 9 to December 30, 2022, in Hainan, China. Here, we report the baseline and characteristics and interim analysis results of the clinical outcomes in those receiving at least one dose of tixagevimab/cilgavimab (300 mg) for pre-exposure prophylaxis.

Results: Among 248 subjects who received tixagevimab/cilgavimab, 229 subjects were included in this analysis. Until March 28, 2023, the median follow-up was 95 days. The mean age of the subjects was 44.4 ± 15.9 years, 11.8% were ≥ 65 years, and 41.5% were male. Fifty-eight (25.3%) subjects had comorbidities, 16.2% subjects had key immune compromised conditions. Seventy-two (32.6%) patients had laboratory-confirmed SARS-CoV-2 infection and/or received healthcare within three months; 71/72 (98.6%) had mild disease, and one (1.4%) was moderate. No COVID-19-related intensive care unit (ICU) admissions, extracorporeal membrane oxygenation utilizations, or death occurred. Two (0.9%) patients required hospitalization. One (0.4%) serious adverse event occurred, which was considered unrelated to tixagevimab/cilgavimab.

Conclusion: Among Chinese patients receiving prophylactic tixagevimab/cilgavimab, the incidence of COVID-19-related hospitalization, ICU admission, or death was low during the Omicron surge. Further randomized controlled trials with larger sample sizes are needed to determine the effectiveness of tixagevimab/cilgavimab in preventing severe COVID-19 outcomes.

Trial registration: The study was registered with clinicaltrial.gov (NCT05917951).