Efficacy of Nirmatrelvir-Ritonavir versus Azvudine for COVID-19 Treatment in Tibet: A Retrospective Study

BACKGROUND: Nirmatrelvir-ritonavir, also known as paxlovid, is a widely used antiviral drug against coronavirus disease 2019 (COVID-19). Azvudine, a drug previously used to treat human immunodeficiency virus-1, has also been used to treat COVID-19 in China. However, only a few clinical studies have evaluated the effects of azvudine. Additionally, studies comparing nirmatrelvir-ritonavir with azvudine have been limited in number. METHODS: We carried out a retrospective case‒control analysis at the Third People’s Hospital of the Tibet Autonomous Region. Eighty-two eligible patients with COVID-19 who received azvudine treatment were included. A total of 145 control patients who received nirmatrelvir-ritonavir treatment were selected by propensity score matching for age, sex, the severity of disease, and initial cycle threshold values. A comparison of the nucleic acid test negative conversion time, the length of hospitalization, and mortality rate was conducted. RESULTS: Overall, the mean nucleic acid test negative conversion time was comparable between the nirmatrelvir-ritonavir and azvudine groups (7.0 [11.0, 15.0] vs 9.0 [6.0, 12.0] days, P=0.064). However, for patients with mild COVID-19, the nucleic acid test negative conversion time was significantly shorter in the nirmatrelvir-ritonavir group than in the azvudine group (6.0 [5.0, 8.0] vs 8.0 [6.0, 11.0] days, P=0.029). The nirmatrelvir-ritonavir group and the azvudine group did not differ significantly in length of hospitalization (8.0 [5.5,10.5] vs 8.0 [5.0,10.0] days, P=0.378). Regarding the mortality rate, there were 4 (2.8%) deaths in the nirmatrelvir-ritonavir group and 3 (3.7%) in the azvudine group (P=0.706). CONCLUSION: Azvudine is generally as effective as nirmatrelvir-ritonavir, but for patients with mild COVID-19, nirmatrelvir-ritonavir could suppress the virus more rapidly. For those who cannot be treated with nirmatrelvir-ritonavir, azvudine might be an effective therapy for COVID-19.