Table 2.
Efficacy outcomes in the RCP and BBIBP study groups in the randomized and non-randomized arms.
| Randomized arm |
Nonrandom arm |
|||
|---|---|---|---|---|
| BBIBP (n = 3607) | RCP (n = 3617) | BBIBP (n = 7832) | RCP (n = 8054) | |
| Symptomatic PCR + Covid-19 two weeks after the 2nd injection | ||||
| Follow-up (person-day) | 479,843 | 480,298 | 778,521 | 850,438 |
| Event | 133 | 121 | 193 | 157 |
| Incidence rate (%95 CI)a | 27.7 (23.4–32.8) | 25.2 (21.1–30.1) | 24.8 (21.5–28.5) | 18.5 (15.8–21.6) |
| Unadjusted hazard ratio (97.5% CI)b | 1.00 | 0.91 (0.71–1.16) | 1.00 | 0.73 (0.59–0.91)b |
| Adjusted hazard ratio (97.5% CI)c | 1.00 | 0.91 (0.71–1.16) | 1.00 | 0.60 (0.48–0.75)c |
| Adjusted hazard ratio (97.5% CI)d | 1.00 | 0.91 (0.71–1.16) | 1.00 | 0.61 (0.48–0.76)d |
| Adjusted hazard ratio (97.5% CI)e | 1.00 | 0.91 (0.71–1.16) | 1.00 | 0.62 (0.49–0.77)e |
| Adjusted hazard ratio (99.1% CI)f | 1.00 | 0.91 (0.67–1.22) | – | – |
| Symptomatic PCR + Covid-19 two weeks after the 2nd injection excluding those with history of covid-19g | ||||
| Follow-up (person-day) | 461,910 | 458,658 | 690,903 | 671,979 |
| Event | 127 | 113 | 176 | 126 |
| Incidence rate (95 % CI)a | 27.5 (23.1–32.7) | 24.6 (20.5–29.6) | 25.5 (21.9–29.5) | 18.7 (15.7–22.3) |
| Unadjusted hazard ratio (97.5% CI)b | 1.00 | 0.89 (0.69–1.15) | 1.00 | 0.73 (0.58–0.91)b |
| Adjusted hazard ratio (97.5% CI)c | 1.00 | 0.87 (0.61–1.12) | 1.00 | 0.61 (0.48–0.78)c |
| Adjusted hazard ratio (97.5% CI)d | 1.00 | 0.90 (0.69–1.16) | 1.00 | 0.62 (0.48–0.78)d |
| Estimated vaccine efficacy | 1.00 | 75.5% (51.8–87.7) | 1.00 | 83.5% (68.6–91.5) |
| Hospitalizations due to Covid-19 two weeks after the 2nd injection (n)h | 1 | 2 | 7 | 1 |
Incidence per 100,000.
Hazard ratios (HR) and their confidence intervals (α error = 0.025) derived from cox proportional hazard model.
HRs from cox proportional hazard model adjusted for age, sex, education.
HRs from cox proportional hazard model adjusted for age, sex, education, and week of the first injection.
HRs from cox proportional hazard model adjusted for age, sex, education, week of the first injection, and history of covid-19.
HRs from cox proportional hazard model adjusted for age, sex, education, week of the first injection, and history of covid-19 taking into account the information fraction using O'Brien-Fleming method (α error = 0.009).
Previous Covid-19 infection was defined as a history of positive PCR test or lung CT scan confirmed by a health professional.
All patients were recovered and discharged with no reports of ICU admission and mortality.