Prevalence of inappropriate use of nirmatrelvir-ritonavir antiviral therapy in hospitalized patients: A multi-centre retrospective study in China

BACKGROUND: Nirmatrelvir-ritonavir (NMVr) is a recently developed antiviral agent for treating coronavirus disease 2019 (COVID-19); however, data describing its appropriate use are scarce. This study examined the prevalence of inappropriate use of NMVr in a Chinese hospital setting. METHODS: A multi-centre retrospective chart review was performed for all hospitalized patients who received NMVr between 15 December 2022 and 15 February 2023 in four university-affiliated hospitals in Hangzhou, China. A multi-disciplinary team of experts developed the evaluation criteria. A group of senior clinical pharmacists examined and verified the suitability of NMVr prescriptions. RESULTS: In total, 247 patients received NMVr during the study period, of which 13.4% (n=31) met all the criteria for appropriate use of NMVr. The main types of inappropriate use of NMVr were delayed initiation of treatment (n=147, 59.5%), no dose adjustment for moderate renal impairment (n=46, 18.6%), use in patients with severe-to-critical COVID-19 (n=49, 19.8%), presence of contra-indicated drug‒drug interactions with other medications (n=36, 14.6%), and prescription for patients without a confirmed diagnosis of COVID-19 (n=36, 14.6%). CONCLUSIONS: The proportion of inappropriate use of NMVr was particularly high in the Chinese hospital setting, highlighting the urgent need to improve the appropriate use of NMVr.