Figure 2. Efficacy of Nirmatrelvir plus Ritonavir (NMV-r) in Preventing Covid-19–Related Hospitalization or Death from Any Cause through Day 28.

Panel A shows efficacy results among patients who were treated within 3 days and within 5 days after symptom onset and who did not receive or were not expected to receive Covid-19 therapeutic monoclonal antibodies at randomization. The average time at risk for an event was computed as the time to the first event or as the time to the last day of participation or day 28, whichever was earlier. The average study follow-up was computed as the time to the last day of participation or day 28, whichever was earlier. Panel B shows the cumulative percentage of patients with Covid-19–related hospitalization or death from any cause through day 28 among patients treated within 5 days after symptom onset. The cumulative percentage was estimated for each treatment group with use of the Kaplan–Meier method. The inset shows the same data on an expanded y axis. Panel C shows subgroup analysis of the differences of the proportions of patients treated within 5 days after symptom onset who had Covid-19–related hospitalization or death from any cause through day 28, estimated for each treatment group with use of the Kaplan–Meier method. P values are based on normal approximation of the data. Study populations are described in Table S2.