Table 3. Estimated Comparative Effectiveness of the BNT162b2 and mRNA-1273 Vaccines in Subgroups Based on Age and Race during a Period Marked by Alpha-Variant Predominance (January 4–July 1, 2021).*.
| Subgroup and Covid-19 Outcome | No. of Events† | 24-Wk Risk (95% CI) | Risk Difference (95% CI) | Risk Ratio (95% CI) | ||
|---|---|---|---|---|---|---|
| BNT162b2 | mRNA-1273 | BNT162b2 | mRNA-1273 | |||
| events/1000 persons | events/1000 persons | |||||
| Age, <70 yr | ||||||
| Documented infection | 516 | 409 | 5.02 (4.46 to 5.39) | 4.56 (3.70 to 5.55) | 0.46 (−0.65 to 1.43) | 1.10 (0.88 to 1.39) |
| Symptomatic Covid-19 | 142 | 91 | 1.30 (1.14 to 1.58) | 0.91 (0.76 to 1.27) | 0.38 (0.00 to 0.68) | 1.42 (1.00 to 1.84) |
| Hospitalization | 102 | 50 | 1.03 (0.76 to 1.23) | 0.48 (0.42 to 0.72) | 0.54 (0.16 to 0.70) | 2.12 (1.23 to 2.48) |
| ICU admission | 32 | 20 | 0.29 (0.17 to 0.40) | 0.19 (0.12 to 0.31) | 0.10 (−0.08 to 0.21) | 1.49 (0.73 to 2.43) |
| Death | — | — | — | — | — | — |
| Age, ≥70 yr | ||||||
| Documented infection | 608 | 497 | 6.31 (5.81 to 6.84) | 4.95 (4.23 to 5.17) | 1.36 (0.93 to 2.31) | 1.27 (1.19 to 1.53) |
| Symptomatic Covid-19 | 179 | 137 | 1.72 (1.49 to 2.01) | 1.33 (1.01 to 1.46) | 0.39 (0.15 to 0.89) | 1.30 (1.11 to 1.82) |
| Hospitalization | 150 | 109 | 1.54 (1.35 to 1.93) | 1.07 (0.73 to 1.13) | 0.47 (0.31 to 1.06) | 1.43 (1.28 to 2.36) |
| ICU admission | 48 | 29 | 0.46 (0.36 to 0.61) | 0.31 (0.17 to 0.39) | 0.15 (0.03 to 0.38) | 1.47 (1.07 to 3.16) |
| Death | 29 | 22 | 0.29 (0.21 to 0.44) | 0.21 (0.14 to 0.31) | 0.08 (−0.04 to 0.24) | 1.37 (0.87 to 2.42) |
| Race, White | ||||||
| Documented infection | 837 | 660 | 5.60 (5.33 to 6.25) | 4.69 (4.06 to 4.86) | 0.90 (0.75 to 1.97) | 1.19 (1.16 to 1.48) |
| Symptomatic Covid-19 | 246 | 178 | 1.56 (1.39 to 1.83) | 1.14 (0.98 to 1.34) | 0.42 (0.16 to 0.76) | 1.37 (1.13 to 1.74) |
| Hospitalization | 190 | 118 | 1.33 (1.11 to 1.65) | 0.80 (0.62 to 0.93) | 0.52 (0.30 to 0.90) | 1.65 (1.35 to 2.36) |
| ICU admission | 54 | 42 | 0.34 (0.27 to 0.46) | 0.30 (0.18 to 0.38) | 0.04 (−0.06 to 0.24) | 1.13 (0.85 to 2.22) |
| Death | 34 | 28 | 0.24 (0.17 to 0.33) | 0.18 (0.11 to 0.25) | 0.05 (−0.04 to 0.19) | 1.30 (0.83 to 2.60) |
| Race, Black | ||||||
| Documented infection | 219 | 201 | 5.95 (4.93 to 7.12) | 5.01 (4.06 to 5.72) | 0.94 (−0.20 to 2.52) | 1.19 (0.96 to 1.57) |
| Symptomatic Covid-19 | 58 | 42 | 1.37 (1.12 to 1.82) | 1.04 (0.82 to 1.58) | 0.33 (−0.21 to 0.84) | 1.32 (0.86 to 1.95) |
| Hospitalization | 49 | 36 | 1.22 (0.91 to 1.71) | 0.86 (0.55 to 1.16) | 0.36 (−0.01 to 0.93) | 1.43 (0.99 to 2.56) |
| ICU admission | — | — | — | — | — | — |
| Death | — | — | — | — | — | — |
*
Persons newly vaccinated with BNT162b2 were matched in a 1:1 ratio to persons newly vaccinated with mRNA-1273 according to the following variables: calendar date, age, sex, race (except for subgroup analyses restricted to race), urbanicity of residence, and geographic location coded as categories of Veterans Integrated Services Network. Estimates were calculated only in analyses in which there were more than 10 outcome events in the vaccine groups under comparison.
†
The sum of events across subgroups may not equal the sum of events in the overall population because the entire analysis (including matching) was repeated after stratification of the population according to baseline characteristics.