Table 3. Summary of Adverse Events through Day 34.*.
| Adverse Event | Nirmatrelvir–Ritonavir (N=654) |
Placebo (N=634) |
|---|---|---|
| no. of participants (%) | ||
| Events that emerged during the treatment period† | ||
| Any event | 169 (25.8) | 153 (24.1) |
| Serious event | 8 (1.2) | 12 (1.9) |
| Maximum event grade of 3 or 4 | 24 (3.7) | 25 (3.9) |
| Maximum event grade of 5 | 0 | 1 (0.2) |
| Event leading to discontinuation of participation in trial | 0 | 1 (0.2) |
| Event leading to discontinuation of nirmatrelvir–ritonavir or placebo; trial participation continued | 16 (2.4) | 5 (0.8) |
| Event leading to dose reduction or temporary discontinuation of nirmatrelvir–ritonavir or placebo | 2 (0.3) | 2 (0.3) |
| Events related to nirmatrelvir–ritonavir or placebo‡ | ||
| Any event | 83 (12.7) | 31 (4.9) |
| Serious event | 0 | 0 |
| Maximum event grade of 3 or 4 | 3 (0.5) | 2 (0.3) |
| Maximum event grade of 5 | 0 | 0 |
| Event leading to discontinuation of participation in trial | 0 | 0 |
| Event leading to discontinuation of nirmatrelvir–ritonavir or placebo; trial participation continued | 11 (1.7) | 2 (0.3) |
| Event leading to dose reduction or temporary discontinuation of nirmatrelvir–ritonavir or placebo | 0 | 1 (0.2) |
*
Safety was evaluated in the population of participants who took at least one dose of nirmatrelvir–ritonavir or placebo and had at least one postbaseline visit. The severity of adverse events was graded according to the Division of AIDS Table for Grading the Severity of Adult and Pediatric Adverse Events, version 2.1 (July 2017).
†
A total of 323 events occurred in the nirmatrelvir–ritonavir group, and 280 occurred in the placebo group.
‡
A total of 109 treatment-related events occurred in the nirmatrelvir–ritonavir group, and 49 occurred in the placebo group.