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

• The proportion of inappropriate use of nirmatrelvir-ritonavir is particularly high in China. • The main types of inappropriate use were delayed initiation of treatment, no dose adjustment for moderate renal impairment, use in severe-to-critical coronavirus disease 2019 (COVID-19), presence of contra-indicated drug‒drug interactions, and prescribing without a diagnosis of COVID-19. • Improvements in how nirmatrelvir-ritonavir is prescribed are needed urgently in the Chinese hospital setting. 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. 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. 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%). 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. [ABSTRACT FROM AUTHOR]