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Oral Simnotrelvir for Adult Patients with Mild-to-Moderate Covid-19
Bin Cao1, Yeming Wang1, Hongzhou Lu1
1From the Departments of Pulmonary and Critical Care Medicine (B.C., Y.W., L.S., J.X., Chen Wang) and Clinical Research and Data Management (X.G.), Institute of Respiratory Medicine in the Chinese Academy of Medical Sciences, National Clinical Research Center for Respiratory Diseases, National Center for Respiratory Medicine, China-Japan Friendship Hospital, Changping Laboratory (B.C., Chen Wang), the Department of Medicine, Non-oncology, Jiangsu Simcere Pharmaceutical (Y.Y.), Clinical and Research Center of Infectious Diseases Beijing Ditan Hospital, Capital Medical University (R.J.), and Chinese Academy of Medical Sciences and Peking Union Medical College (Chen Wang), Beijing, the Department of Infectious Diseases, Third People's Hospital of Shenzhen, National Clinical Research Center for Infectious Diseases, Shenzhen (H.L., F.W.), Jin Yin-tan Hospital (C.H., F.G.) and Wuhan Institute of Virology, Chinese Academy of Sciences (L.Z.), Wuhan, the Public Health Clinical Center of Chengdu, Chengdu (Z.C.), Tianjin First Central Hospital, Tianjin (Y.L.), the Department of Cardiology, Hainan Third People's Hospital, Sanya (L.L.), the Department of Respiratory Medicine, Guangzhou Eighth People's Hospital, Guangzhou (P.P.), the Department of Clinical Statistics and Data Management, Jiangsu Simcere Pharmaceutical (H.H.), the Department of Infection and Immunity, Shanghai Public Health Clinical Center (Y.S.), and the Department of Infectious Diseases, Zhongshan Hospital (B.H.), Fudan University, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (J.S., Y.X.), and the Department of Liver Surgery and Transplantation, Liver Cancer Institute, Zhongshan Hospital, Fudan University, and Key Laboratory of Carcinogenesis and Cancer Invasion of the Ministry of Education (J.F.), Shanghai, the Second Hospital of Nanjing (C.C.), Jiangsu Simcere Pharmaceutical (R.T.), and State Key Laboratory of Neurology and Oncology Drug Development (R.T.), Nanjing, the First Affiliated Hospital of Xiamen University, Xiamen (X. Yao), Guizhou Provincial People's Hospital, Guiyang (X. Ye, H.Z.), the Second Department of Infection, Shandong Public Health Clinical Center, Jinan (C.L.), Xuzhou Infectious Diseases Hospital, Xuzhou (Chunying Wang), and Central People's Hospital of Zhanjiang, Zhanjiang (Z.Y.) - all in China.
Simnotrelvir, an oral protease inhibitor, significantly reduced symptom duration for COVID-19 patients. Early treatment with simnotrelvir plus ritonavir offers a promising therapeutic option for coronavirus disease 2019.
Area of Science:
- Virology
- Infectious Diseases
- Pharmacology
Background:
- Simnotrelvir is an oral 3-chymotrypsin-like protease inhibitor with demonstrated in vitro activity against SARS-CoV-2.
- Previous phase 1B trials indicated potential efficacy for simnotrelvir in treating COVID-19.
Purpose of the Study:
- To evaluate the efficacy and safety of simnotrelvir plus ritonavir in patients with mild-to-moderate COVID-19.
- To determine the impact of early simnotrelvir administration on symptom resolution time and viral load.
Main Methods:
- A phase 2-3, double-blind, randomized, placebo-controlled trial involving 1208 patients with mild-to-moderate COVID-19.
- Patients received either 750 mg simnotrelvir plus 100 mg ritonavir or placebo twice daily for 5 days, initiated within 72 hours of symptom onset.
- The primary endpoint was the time to sustained symptom resolution; viral load and adverse events were also assessed.
Main Results:
- Simnotrelvir significantly shortened the time to sustained symptom resolution compared to placebo (180.1 hours vs. 216.0 hours).
- A greater decrease in viral load was observed in the simnotrelvir group by day 5.
- The incidence of adverse events was higher in the simnotrelvir group (29.0%) but mostly mild or moderate.
Conclusions:
- Early administration of simnotrelvir plus ritonavir effectively shortened symptom duration in adult COVID-19 patients.
- The treatment demonstrated an acceptable safety profile, suggesting it as a viable therapeutic option.
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