Pharmacotherapeutic group: vaccines, viral vaccines, ATC code: J07BN01
Mechanism of action
The nucleoside modified messenger RNA in Comirnaty is formulated in lipid nanoparticles, which enable delivery of the non‑replicating RNA into host cells to direct transient expression of the SARS‑CoV-2 S antigen. The mRNA codes for membrane-anchored, full-length S with two point mutations within the central helix. Mutation of these two amino acids to proline locks S in an antigenically preferred prefusion conformation. The vaccine elicits both neutralising antibody and cellular immune responses to the spike (S) antigen, which may contribute to protection against COVID-19.
Efficacy
Omicron-adapted Comirnaty
Immunogenicity in children 5 to 11 years of age (i.e. 5 to less than 12 years of age) – after the booster (fourth dose) with Comirnaty and Comirnaty Original/Omicron BA.4-5
In an analysis of a subset from Study 6, 103 participants 5 to 11 years of age who had previously received a 2-dose primary series and booster dose with Comirnaty received a booster (fourth dose) of Comirnaty Original/Omicron BA.4-5. Results include immunogenicity data from a comparator subset of participants 5 to 11 years of age in Study 3 who received 3 doses of Comirnaty. In participants 5 to 11 years of age who received a fourth dose of Comirnaty Original/Omicron BA.4-5 and participants 5 to 11 years of age who received a third dose of Comirnaty, 57.3% and 58.4% were positive for SARS‑CoV-2 at baseline, respectively.
The immune response 1 month after a booster dose (fourth dose), Comirnaty Original/Omicron BA.4‑5 elicited generally similar Omicron BA.4/BA.5-specific neutralising titres compared with the titres in the comparator group who received 3 doses of Comirnaty. Comirnaty Original/Omicron BA.4-5 also elicited similar reference strain-specific titres compared with the titres in the comparator group.
The vaccine immunogenicity results after a booster dose in participants 5 to 11 years of age are presented in Table 3.
Table 3. Study 6 – Geometric mean ratio and Geometric mean titres – participants with or without evidence of infection – 5 to 11 years of age – evaluable immunogenicity population
| SARS-CoV-2 neutralisation assay | Sampling time pointa | Vaccine Group (as Assigned/Randomised) |
| Study 6 Comirnaty (Original/Omicron BA.4/BA.5) 10 mcg Dose 4 and 1 Month After Dose 4 | Study 3 Comirnaty 10 mcg Dose 3 and 1 Month After Dose 3 | Study 6 Comirnaty (Original/Omicron BA.4/BA.5)/Comirnaty 10 mcg |
| nb | GMTc (95% CIc) | nb | GMTc (95% CIc) | GMRd (95% CId) |
| Omicron BA.4-5 - NT50 (titre)e | Pre-vaccination | 102 | 488.3 (361.9, 658.8) | 112 | 248.3 (187.2, 329.5) | - |
| 1 month | 102 | 2 189.9 (1 742.8, 2 751.7) | 113 | 1 393.6 (1 175.8, 1 651.7) | 1.12 (0.92, 1.37) |
| Reference strain - NT50 (titre)e | Pre-vaccination | 102 | 2 904.0 (2 372.6, 3 554.5) | 113 | 1 323.1 (1 055.7, 1 658.2) | - |
| 1 month | 102 | 8 245.9 (7 108.9, 9 564.9) | 113 | 7 235.1 (6 331.5, 8 267.8) | - |
Abbreviations: CI = confidence interval; GMR = geometric mean ratio; GMT = geometric mean titre; LLOQ = lower limit of quantitation; LS = least square; N-binding = SARS-CoV-2 nucleoprotein–binding; NT50 = 50% neutralising titre; SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2.
a. Protocol-specified timing for blood sample collection.
b. n = Number of participants with valid and determinate assay results for the specified assay at the given sampling time point.
c. GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titres and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5 × LLOQ.
d. GMRs and 2-sided CIs were calculated by exponentiating the difference of LS Means for the assay and the corresponding CIs based on analysis of log-transformed assay results using a linear regression model with baseline log-transformed neutralising titres, postbaseline infection status, and vaccine group as covariates.
e. SARS-CoV-2 NT50 were determined using a validated 384-well assay platform (original strain [USA‑WA1/2020, isolated in January 2020] and Omicron B.1.1.529 subvariant BA.4/BA.5).
Immunogenicity in vaccine-naïve participants 12 years of age and older – after a single dose of Comirnaty Omicron XBB.1.5
In an analysis of a subset from Study 13, 302 vaccine-naïve participants 12 years of age and older who were considered to be SARS-CoV-2 positive at baseline and who received 1 dose of Comirnaty Omicron XBB.1.5 were compared to participants who received Comirnaty Omicron XBB.1.5 after at least 3 doses of an mRNA COVID-19 vaccine. The evaluable immunogenicity population who were vaccine-naïve had a median age of 36.0 years and comprised of 62.6% White and 50.7% Hispanic/Latino participants. The evaluable immunogenicity population who were vaccine‑experienced (n=296) had a median age of 55 years and comprised of 79.4% White and 18.6% Hispanic/Latino.
Neutralizing titres against Omicron XBB.1.5 increased from baseline to 1 month after study vaccination and were greater in participants receiving Comirnaty Omicron XBB.1.5 as a single dose compared with participants who received Comirnaty Omicron XBB.1.5 after at least 3 doses of an mRNA COVID-19 vaccine. Noninferiority was met with respect to the geometric mean ratio (GMR) of Omicron XBB.1.5-neutralizing titres, and the difference in seroresponse to the XBB.1.5 strain in vaccine-naïve participants compared to participants who received Comirnaty Omicron XBB.1.5 after at least 3 doses of an mRNA COVID-19 vaccine (Table 4).
Table 4. Geometric mean ratio and difference in percentages of participants with seroresponse – Study 13 vaccine-naïve and subset of vaccine-experienced – evaluable immunogenicity population
| | | Vaccine group (as assigned) | Group comparison |
| | | Vaccine-naïve Comirnaty Omicron XBB.1.5 30 mcg | Vaccine-experienced Comirnaty Omicron XBB.1.5 30 mcg | Vaccine-naïve Comirnaty Omicron XBB.1.5 30 mcg / Vaccine-experienced Comirnaty Omicron XBB.1.5 30 mcg |
| SARS-CoV-2 neutralization assay Omicron XBB.1.5 - NT50 (titre)e | Sampling time pointa | nb | GMTc (95% CIc) | nb | GMTc (95% CIc) | GMRd (95% CId) |
| Geometric mean 50% neutralising titre (GMT) | 1 month | 299 | 4 373.4 (3 757.1, 5 090.9) | 296 | 2 915.7 (2 462.4, 3 452.5) | 1.93 (1.52, 2.44)f |
| | Sampling time pointa | Ng | nh (%) (95% CIi) | Ng | nh (%) (95% CIi) | Difference %j | (95% CIk) |
| Seroresponse rate (%) for 50% neutralising titre | 1 month | 298 | 253 (84.9) (80.3, 88.8) | 295 | 218 (73.9) (68.5, 78.8) | 7.31 | (1.34, 13.28)l |
Abbreviations: CI = confidence interval; GMR = geometric mean ratio; GMT = geometric mean titre; LLOQ = lower limit of quantitation; NT50 = 50% neutralizing titre; SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2.
a. Protocol-specified timing for blood sample collection.
b. n = Number of participants with valid and determinate assay results for the specified assay at both the pre−vaccination time point and the given sampling time point.
c. GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titres and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5 × LLOQ.
d. GMRs and the corresponding 2-sided 95% CIs were calculated by exponentiating the difference in least square means and the corresponding CIs based on a linear regression model with baseline assay results (log scale), age, and vaccine group as covariates.
e. SARS-CoV-2 NT50 were determined using a validated 384-well assay platform (Omicron subvariant XBB.1.5).
f. Noninferiority is declared if the lower bound of the 2-sided 95% CI for the GMR is greater than 0.67.
g. N = number of participants with valid and determinate assay results for the specified assay at both the pre−vaccination time point and the given sampling time point. These values are the denominators for the percentage calculations.
h. n = Number of participants with a seroresponse for the given assay at the given sampling time point.
i. Exact 2-sided CI, based on the Clopper and Pearson method.
j. Difference in proportions, expressed as a percentage.
k. 2-Sided CI, based on the Miettinen and Nurminen method stratified by baseline neutralizing titre category (< median, ≥ median) and age group (< median, ≥ median). The median of baseline neutralizing titres and median age was calculated based on the pooled data in 2 comparator groups.
l. Noninferiority is declared if the lower bound of the 2-sided 95% CI for the difference in percentages of participants with seroresponse is > -10%.
Immunogenicity in participants 12 years of age and older – after a single dose of Comirnaty Omicron JN.1
In an analysis of a subset from Study 13, 212 participants 12 years of age and older who received 1 dose of Comirnaty Omicron JN.1 were compared to 200 participants who received Comirnaty Omicron XBB.1.5 after receiving at least 3 doses of an mRNA COVID-19 vaccine. The evaluable immunogenicity population who received Comirnaty Omicron JN.1 had a median age of 54.5 years and comprised of 69.3% White and 23.1% Hispanic/Latino participants, and 87.3% were positive for SARS‑CoV-2 at baseline, and 89.2% had previously received a COVID-19 vaccine.
Neutralizing titres and seroresponse against Omicron JN.1 or Omicron XBB.5 in participants receiving Comirnaty Omicron JN.1 or Comirnaty Omicron XBB.1.5 are presented in Table 5.
Table 5. Geometric mean titres and percentage of participants achieving seroresponse – Comirnaty JN.1 or Comirnaty XBB.1.5 – participants 12 years of age and older – evaluable immunogenicity population
| | | Comirnaty Omicron JN.1 30 mcg | Comirnaty Omicron XBB.1.5 30 mcg |
| Geometric mean 50% neutralizing titre (GMT) | Sampling time pointa | nb | GMTc (95% CIc) | nb | GMTc (95% CIc) |
| SARS-CoV-2 neutralisation assay – Omicron JN.1 - NT50 (titre)d | Pre-vaccination | 211 | 190.4 (153.6, 235.9) | 198 | 155.5 (126.6, 190.8) |
| 1 month | 212 | 2203.3 (1855.7, 2616.0) | 199 | 1133.8 (950.7, 1352.2) |
| SARS-CoV-2 neutralisation assay – Omicron XBB.1.5 – NT50 (titre)e | Pre-vaccination | 212 | 290.3 (233.0, 361.6) | 200 | 219.2 (177.5, 270.7) |
| 1 month | 212 | 2364.4 (1917.4, 2915.6) | 200 | 2848.1 (2341.9, 3463.8) |
| Seroresponse rate for 50% neutralising titre | Sampling time pointa | Nf | ng (%) (95% CIh) | Nb | ng (%) (95% CIh) |
| SARS-CoV-2 neutralisation assay – Omicron JN.1 - NT50 (titre)d | 1 month | 211 | 149 (70.6) (64.0, 76.7) | 197 | 129 (65.5) (58.4, 72.1) |
| SARS-CoV-2 neutralisation assay – Omicron XBB.1.5 – NT50 (titre)e | 1 month | 212 | 128 (60.4) (53.5, 67.0) | 200 | 164 (82.0) (76.0, 87.1) |
Abbreviations: GMT = geometric mean titer; LLOQ = lower limit of quantitation; NT50 = 50% neutralizing titre; SARS‑CoV-2 = severe acute respiratory syndrome coronavirus 2.
a. Protocol-specified timing for blood sample collection.
b. n = Number of participants with valid and determinate assay results for the specified assay at the given sampling time point.
c. GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5 × LLOQ.
d. SARS-CoV-2 NT50 were determined using a validated 384-well assay platform (Omicron subvariant JN.1).
e. SARS-CoV-2 NT50 were determined using a validated 384-well assay platform (Omicron subvariant XBB.1.5).
f. N = number of participants with valid and determinate assay results for the specified assay at both the prevaccination time point and the given sampling time point. These values are the denominators for the percentage calculations.
g. n = Number of participants with a seroresponse for the given assay at the given sampling time point.
h. Exact 2-sided CI, based on the Clopper and Pearson method.
Immunogenicity in participants 12 years of age and older – after a single dose of Comirnaty Omicron KP.2
In an analysis of a subset from Study 13, 100 participants 18 years of age and older who received 1 dose of Comirnaty Omicron KP.2 were compared to 194 participants who received 1 dose of Comirnaty Omicron JN.1. The evaluable immunogenicity population who received Comirnaty Omicron KP.2 had a median age of 55.0 years and comprised of 75.0% White and 15.0% Hispanic/Latino participants, 91.0% were positive for SARS‑CoV-2 at baseline, and 90.0% had previously received a COVID-19 vaccine.
Neutralizing titres and seroresponse against Omicron KP.2 and Omicron JN.1 in participants receiving Comirnaty Omicron KP.2 or Comirnaty Omicron JN.1 are presented in Table 6.
Table 6. Geometric mean titres and percentage of participants achieving seroresponse – Comirnaty KP.2 or Comirnaty JN.1 – participants 18 years of age and older – evaluable immunogenicity population
| | | Comirnaty Omicron KP.2 30 mcg | Comirnaty Omicron JN.1 30 mcg |
| Geometric mean 50% neutralizing titre (GMT) | Sampling time pointa | nb | GMTc (95% CIc) | nb | GMTc (95% CIc) |
| SARS-CoV-2 neutralisation assay – Omicron KP.2 – NT50 (titre)d | Pre-vaccination | 99 | 207.6 (150.0, 287.4) | 194 | 78.3 (64.2, 95.6) |
| 1 month | 100 | 2256.5 (1660.2, 3067.0) | 194 | 873.3 (706.1, 1080.2) |
| SARS-CoV-2 neutralisation assay – Omicron JN.1 – NT50 (titre)e | Pre-vaccination | 100 | 492.5 (359.8, 674.0) | 194 | 185.1 (148.1, 231.4) |
| 1 month | 100 | 4319.5 (3280.7, 5687.2) | 194 | 2088.6 (1743.9, 2501.5) |
| Seroresponse rate for 50% neutralising titre | Sampling time pointa | Nf | ng (%) (95% CIh) | Nb | ng (%) (95% CIh) |
| SARS-CoV-2 neutralisation assay – Omicron KP.2 – NT50 (titre)d | 1 month | 99 | 76 (76.8) (67.2, 84.7) | 194 | 130 (67.0) (59.9, 73.6) |
| SARS-CoV-2 neutralisation assay – Omicron JN.1 – NT50 (titre)e | 1 month | 100 | 64 (64.0) (53.8, 73.4) | 194 | 137 (70.6) (63.7, 76.9) |
Abbreviations: GMT = geometric mean titre; LLOQ = lower limit of quantitation; NT50 = 50% neutralizing titre; SARS‑CoV-2 = severe acute respiratory syndrome coronavirus 2.
a. Protocol-specified timing for blood sample collection.
b. n = Number of participants with valid and determinate assay results for the specified assay at the given sampling time point.
c. GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titres and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5 × LLOQ.
d. SARS-CoV-2 NT50 were determined using a validated 384-well assay platform (Omicron subvariant KP.2).
e. SARS-CoV-2 NT50 were determined using a validated 384-well assay platform (Omicron subvariant JN.1).
f. N = number of participants with valid and determinate assay results for the specified assay at both the prevaccination time point and the given sampling time point. These values are the denominators for the percentage calculations.
g. n = Number of participants with a seroresponse for the given assay at the given sampling time point.
h. Exact 2-sided CI, based on the Clopper and Pearson method.
Initially approved Comirnaty vaccine
Study 2 is a multicentre, multinational, Phase 1/2/3 randomised, placebo-controlled, observer-blind dose-finding, vaccine candidate selection and efficacy study in participants 12 years of age and older. Randomisation was stratified by age: 12 to 15 years of age, 16 to 55 years of age, or 56 years of age and older, with a minimum of 40% of participants in the ≥ 56-year stratum. The study excluded participants who were immunocompromised and those who had previous clinical or microbiological diagnosis of COVID-19. Participants with pre-existing stable disease, defined as disease not requiring significant change in therapy or hospitalisation for worsening disease during the 6 weeks before enrolment, were included as were participants with known stable infection with human immunodeficiency virus (HIV), hepatitis C virus (HCV) or hepatitis B virus (HBV).
Efficacy in participants 16 years of age and older – after 2 doses
In the Phase 2/3 portion of Study 2, based on data accrued through 14 November 2020, approximately 44 000 participants were randomised equally and were to receive 2 doses of the initially approved COVID-19 mRNA Vaccine or placebo. The efficacy analyses included participants that received their second vaccination within 19 to 42 days after their first vaccination. The majority (93.1%) of vaccine recipients received the second dose 19 days to 23 days after Dose 1. Participants are planned to be followed for up to 24 months after Dose 2, for assessments of safety and efficacy against COVID-19. In the clinical study, participants were required to observe a minimum interval of 14 days before and after administration of an influenza vaccine in order to receive either placebo or COVID-19 mRNA Vaccine. In the clinical study, participants were required to observe a minimum interval of 60 days before or after receipt of blood/plasma products or immunoglobulins within through conclusion of the study in order to receive either placebo or COVID‑19 mRNA Vaccine.
The population for the analysis of the primary efficacy endpoint included 36 621 participants 12 years of age and older (18 242 in the COVID-19 mRNA Vaccine group and 18 379 in the placebo group) who did not have evidence of prior infection with SARS-CoV-2 through 7 days after the second dose. In addition, 134 participants were between the ages of 16 to 17 years of age (66 in the COVID-19 mRNA Vaccine group and 68 in the placebo group) and 1 616 participants 75 years of age and older (804 in the COVID-19 mRNA Vaccine group and 812 in the placebo group).
At the time of the primary efficacy analysis, participants had been followed for symptomatic COVID‑19 for in total 2 214 person‑years for the COVID-19 mRNA Vaccine and in total 2 222 person‑years in the placebo group.
There were no meaningful clinical differences in overall vaccine efficacy in participants who were at risk of severe COVID-19 including those with 1 or more comorbidities that increase the risk of severe COVID-19 (e.g. asthma, body mass index (BMI) ≥ 30 kg/m2, chronic pulmonary disease, diabetes mellitus, hypertension).
The vaccine efficacy information is presented in Table 7.
Table 7. Vaccine efficacy – First COVID-19 occurrence from 7 days after Dose 2, by age subgroup – participants without evidence of infection prior to 7 days after Dose 2 – evaluable efficacy (7 days) population
| First COVID-19 occurrence from 7 days after Dose 2 in participants without evidence of prior SARS‑CoV-2 infection* |
| Subgroup | COVID‑19 mRNA Vaccine Na = 18 198 Cases n1b Surveillance timec (n2d) | Placebo Na = 18 325 Cases n1b Surveillance timec (n2d) | Vaccine efficacy % (95% CI)e |
| All participants | 8 2.214 (17 411) | 162 2.222 (17 511) | 95.0 (90.0, 97.9) |
| 16 to 64 years | 7 1.706 (13 549) | 143 1.710 (13 618) | 95.1 (89.6, 98.1) |
| 65 years and older | 1 0.508 (3 848) | 19 0.511 (3 880) | 94.7 (66.7, 99.9) |
| 65 to 74 years | 1 0.406 (3 074) | 14 0.406 (3 095) | 92.9 (53.1, 99.8) |
| 75 years and older | 0 0.102 (774) | 5 0.106 (785) | 100.0 (-13.1, 100.0) |
Note: Confirmed cases were determined by Reverse Transcription-Polymerase Chain Reaction (RT‑PCR) and at least 1 symptom consistent with COVID-19 [*Case definition: (at least 1 of) fever, new or increased cough, new or increased shortness of breath, chills, new or increased muscle pain, new loss of taste or smell, sore throat, diarrhoea or vomiting.]
* Participants who had no serological or virological evidence (prior to 7 days after receipt of the last dose) of past SARS-CoV-2 infection (i.e. N-binding antibody [serum] negative at Visit 1 and SARS-CoV-2 not detected by nucleic acid amplification tests (NAAT) [nasal swab] at Visits 1 and 2), and had negative NAAT (nasal swab) at any unscheduled visit prior to 7 days after Dose 2 were included in the analysis.
a. N = Number of participants in the specified group.
b. n1 = Number of participants meeting the endpoint definition.
c. Total surveillance time in 1 000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from 7 days after Dose 2 to the end of the surveillance period.
d. n2 = Number of participants at risk for the endpoint.
e. Two‑sided confidence interval (CI) for vaccine efficacy is derived based on the Clopper and Pearson method adjusted to the surveillance time. CI not adjusted for multiplicity.
Efficacy of COVID-19 mRNA Vaccine in preventing first COVID-19 occurrence from 7 days after Dose 2 compared to placebo was 94.6% (95% confidence interval of 89.6% to 97.6%) in participants 16 years of age and older with or without evidence of prior infection with SARS-CoV-2.
Additionally, subgroup analyses of the primary efficacy endpoint showed similar efficacy point estimates across genders, ethnic groups, and participants with medical comorbidities associated with high risk of severe COVID-19.
Updated efficacy analyses were performed with additional confirmed COVID-19 cases accrued during blinded placebo-controlled follow-up, representing up to 6 months after Dose 2 in the efficacy population.
The updated vaccine efficacy information is presented in Table 8.
Table 8. Vaccine efficacy – First COVID-19 occurrence from 7 days after Dose 2, by age subgroup – participants without evidence of prior SARS-CoV-2 infection* prior to 7 days after Dose 2 – evaluable efficacy (7 days) population during the placebo‑controlled follow-up period
| Subgroup | COVID‑19 mRNA Vaccine Na=20 998 Cases n1b Surveillance timec (n2d) | Placebo Na=21 096 Cases n1b Surveillance timec (n2d) | Vaccine efficacy % (95% CIe) |
| All participantsf | 77 6.247 (20 712) | 850 6.003 (20 713) | 91.3 (89.0, 93.2) |
| 16 to 64 years | 70 4.859 (15 519) | 710 4.654 (15 515) | 90.6 (87.9, 92.7) |
| 65 years and older | 7 1.233 (4 192) | 124 1.202 (4 226) | 94.5 (88.3, 97.8) |
| 65 to 74 years | 6 0.994 (3 350) | 98 0.966 (3 379) | 94.1 (86.6, 97.9) |
| 75 years and older | 1 0.239 (842) | 26 0.237 (847) | 96.2 (76.9, 99.9) |
Note: Confirmed cases were determined by Reverse Transcription-Polymerase Chain Reaction (RT‑PCR) and at least 1 symptom consistent with COVID-19 (symptoms included: fever; new or increased cough; new or increased shortness of breath; chills; new or increased muscle pain; new loss of taste or smell; sore throat; diarrhoea; vomiting).
* Participants who had no evidence of past SARS-CoV-2 infection (i.e. N-binding antibody [serum] negative at Visit 1 and SARS-CoV-2 not detected by NAAT [nasal swab] at Visits 1 and 2), and had negative NAAT (nasal swab) at any unscheduled visit prior to 7 days after Dose 2 were included in the analysis.
a. N = Number of participants in the specified group.
b. n1 = Number of participants meeting the endpoint definition.
c. Total surveillance time in 1 000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from 7 days after Dose 2 to the end of the surveillance period.
d. n2 = Number of participants at risk for the endpoint.
e. Two-sided 95% confidence interval (CI) for vaccine efficacy is derived based on the Clopper and Pearson method adjusted to the surveillance time.
f. Included confirmed cases in participants 12 to 15 years of age: 0 in the COVID‑19 mRNA Vaccine group; 16 in the placebo group.
In the updated efficacy analysis, efficacy of COVID-19 mRNA Vaccine in preventing first COVID-19 occurrence from 7 days after Dose 2 compared to placebo was 91.1% (95% CI of 88.8% to 93.0%) during the period when Wuhan/wild-type and Alpha variants were the predominant circulating strains in participants in the evaluable efficacy population with or without evidence of prior infection with SARS-CoV-2.
Additionally, the updated efficacy analyses by subgroup showed similar efficacy point estimates across sexes, ethnic groups, geography and participants with medical comorbidities and obesity associated with high risk of severe COVID-19.
Efficacy against severe COVID‑19
Updated efficacy analyses of secondary efficacy endpoints supported benefit of the COVID-19 mRNA Vaccine in preventing severe COVID‑19.
As of 13 March 2021, vaccine efficacy against severe COVID-19 is presented only for participants with or without prior SARS-CoV-2 infection (Table 9) as the COVID-19 case counts in participants without prior SARS-CoV-2 infection were the same as those in participants with or without prior SARS-CoV-2 infection in both the COVID‑19 mRNA Vaccine and placebo groups.
Table 9. Vaccine efficacy – First severe COVID-19 occurrence in participants with or without prior SARS-CoV-2 infection based on the Food and Drug Administration (FDA)* after Dose 1 or from 7 days after Dose 2 in the placebo-controlled follow-up
| | COVID‑19 mRNA Vaccine Cases n1a Surveillance time (n2b) | Placebo Cases n1a Surveillance time (n2b) | Vaccine efficacy % (95% CIc) |
| After Dose 1d | 1 8.439e (22 505) | 30 8.288e (22 435) | 96.7 (80.3, 99.9) |
| 7 days after Dose 2f | 1 6.522g (21 649) | 21 6.404g (21 730) | 95.3 (70.9, 99.9) |
Note: Confirmed cases were determined by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and at least 1 symptom consistent with COVID-19 (symptoms included: fever; new or increased cough; new or increased shortness of breath; chills; new or increased muscle pain; new loss of taste or smell; sore throat; diarrhoea; vomiting).
* Severe illness from COVID‑19 as defined by FDA is confirmed COVID‑19 and presence of at least 1 of the following:
• Clinical signs at rest indicative of severe systemic illness (respiratory rate ≥ 30 breaths per minute, heart rate ≥ 125 beats per minute, saturation of oxygen ≤ 93% on room air at sea level, or ratio of arterial oxygen partial pressure to fractional inspired oxygen < 300 mm Hg);
• Respiratory failure [defined as needing high‑flow oxygen, noninvasive ventilation, mechanical ventilation or extracorporeal membrane oxygenation (ECMO)];
• Evidence of shock (systolic blood pressure < 90 mm Hg, diastolic blood pressure < 60 mm Hg, or requiring vasopressors);
• Significant acute renal, hepatic, or neurologic dysfunction;
• Admission to an Intensive Care Unit;
• Death.
a. n1 = Number of participants meeting the endpoint definition.
b. n2 = Number of participants at risk for the endpoint.
c. Two-side confidence interval (CI) for vaccine efficacy is derived based on the Clopper and Pearson method adjusted to the surveillance time.
d. Efficacy assessed based on the Dose 1 all available efficacy (modified intention-to-treat) population that included all randomised participants who received at least 1 dose of study intervention.
e. Total surveillance time in 1 000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from Dose 1 to the end of the surveillance period.
f. Efficacy assessed based on the evaluable efficacy (7 Days) population that included all eligible randomised participants who receive all dose(s) of study intervention as randomised within the predefined window, have no other important protocol deviations as determined by the clinician.
g. Total surveillance time in 1 000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from 7 days after Dose 2 to the end of the surveillance period.
Efficacy and immunogenicity in adolescents 12 to 15 years of age – after 2 doses
In an initial analysis of Study 2 in adolescents 12 to 15 years of age (representing a median follow-up duration of > 2 months after Dose 2) without evidence of prior infection, there were no cases in 1 005 participants who received the vaccine and 16 cases out of 978 who received placebo. The point estimate for efficacy is 100% (95% confidence interval 75.3, 100.0). In participants with or without evidence of prior infection there were 0 cases in the 1 119 who received vaccine and 18 cases in 1 110 participants who received placebo. This also indicates the point estimate for efficacy is 100% (95% confidence interval 78.1, 100.0).
Updated efficacy analyses were performed with additional confirmed COVID-19 cases accrued during blinded placebo-controlled follow-up, representing up to 6 months after Dose 2 in the efficacy population.
In the updated efficacy analysis of Study 2 in adolescents 12 to 15 years of age without evidence of prior infection, there were no cases in 1 057 participants who received the vaccine and 28 cases out of 1 030 who received placebo. The point estimate for efficacy is 100% (95% confidence interval 86.8, 100.0) during the period when Alpha variant was the predominant circulating strain. In participants with or without evidence of prior infection there were 0 cases in the 1 119 who received vaccine and 30 cases in 1 109 participants who received placebo. This also indicates the point estimate for efficacy is 100% (95% confidence interval 87.5, 100.0).
In Study 2, an analysis of SARS-CoV-2 neutralising titres 1 month after Dose 2 was conducted in a randomly selected subset of participants who had no serological or virological evidence of past SARS‑CoV-2 infection up to 1 month after Dose 2, comparing the response in adolescents 12 to 15 years of age (n = 190) to participants 16 to 25 years of age (n = 170).
The ratio of the geometric mean titres (GMT) in the 12 to 15 years of age group to the 16 to 25 years of age group was 1.76, with a 2‑sided 95% CI of 1.47 to 2.10. Therefore, the 1.5‑fold noninferiority criterion was met as the lower bound of the 2‑sided 95% CI for the geometric mean ratio [GMR] was > 0.67.
Efficacy and immunogenicity in children 5 to 11 years of age (i.e. 5 to less than 12 years of age) – after 2 doses
Study 3 is a Phase 1/2/3 study comprised of an open-label vaccine dose‑finding portion (Phase 1) and a multicentre, multinational, randomised, saline placebo-controlled, observer-blind efficacy portion (Phase 2/3) that has enrolled participants 5 to 11 years of age. The majority (94.4%) of randomised vaccine recipients received the second dose 19 days to 23 days after Dose 1.
Initial descriptive vaccine efficacy results in children 5 to 11 years of age without evidence of prior SARS‑CoV‑2 infection are presented in Table 10. No cases of COVID‑19 were observed in either the vaccine group or the placebo group in participants with evidence of prior SARS-CoV-2 infection.
Table 10. Vaccine efficacy – First COVID-19 occurrence from 7 days after Dose 2: Without evidence of infection prior to 7 days after Dose 2 – Phase 2/3 – Children 5 to 11 years of age evaluable efficacy population
| First COVID-19 occurrence from 7 days after Dose 2 in children 5 to 11 years of age without evidence of prior SARS‑CoV‑2 infection* |
| | COVID‑19 mRNA Vaccine 10 mcg/dose Na=1 305 Cases n1b Surveillance timec (n2d) | Placebo Na=663 Cases n1b Surveillance timec (n2d) | Vaccine efficacy % (95% CI) |
| Children 5 to 11 years of age | 3 0.322 (1 273) | 16 0.159 (637) | 90.7 (67.7, 98.3) |
Note: Confirmed cases were determined by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and at least 1 symptom consistent with COVID-19 (symptoms included: fever; new or increased cough; new or increased shortness of breath; chills; new or increased muscle pain; new loss of taste or smell; sore throat; diarrhoea; vomiting).
* Participants who had no evidence of past SARS-CoV-2 infection (i.e. N-binding antibody [serum] negative at Visit 1 and SARS-CoV-2 not detected by NAAT [nasal swab] at Visits 1 and 2), and had negative NAAT (nasal swab) at any unscheduled visit prior to 7 days after Dose 2 were included in the analysis.
a. N = Number of participants in the specified group.
b. n1 = Number of participants meeting the endpoint definition.
c. Total surveillance time in 1 000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from 7 days after Dose 2 to the end of the surveillance period.
d. n2 = Number of participants at risk for the endpoint.
Pre-specified hypothesis-driven efficacy analysis was performed with additional confirmed COVID‑19 cases accrued during blinded placebo-controlled follow-up, representing up to 6 months after Dose 2 in the efficacy population.
In the efficacy analysis of Study 3 in children 5 to 11 years of age without evidence of prior infection, there were 10 cases in 2 703 participants who received the vaccine and 42 cases out of 1 348 who received placebo. The point estimate for efficacy is 88.2% (95% confidence interval 76.2, 94.7) during the period when Delta variant was the predominant circulating strain. In participants with or without evidence of prior infection there were 12 cases in the 3 018 who received vaccine and 42 cases in 1 511 participants who received placebo. The point estimate for efficacy is 85.7% (95% confidence interval 72.4, 93.2).
In Study 3, an analysis of SARS-CoV-2 50% neutralising titres (NT50) 1 month after Dose 2 in a randomly selected subset of participants demonstrated effectiveness by immunobridging of immune responses comparing children 5 to 11 years of age (i.e. 5 to less than 12 years of age) in the Phase 2/3 part of Study 3 to participants 16 to 25 years of age in the Phase 2/3 part of Study 2 who had no serological or virological evidence of past SARS‑CoV-2 infection up to 1 month after Dose 2, meeting the pre-specified immunobridging criteria for both the geometric mean ratio (GMR) and the seroresponse difference with seroresponse defined as achieving at least 4-fold rise in SARS-CoV-2 NT50 from baseline (before Dose 1).
The GMR of the SARS-CoV-2 NT50 1 month after Dose 2 in children 5 to 11 years of age (i.e. 5 to less than 12 years of age) to that of young adults 16 to 25 years of age was 1.04 (2‑sided 95% CI: 0.93, 1.18). Among participants without prior evidence of SARS-CoV-2 infection up to 1 month after Dose 2, 99.2% of children 5 to 11 years of age and 99.2% of participants 16 to 25 years of age had a seroresponse at 1 month after Dose 2. The difference in proportions of participants who had seroresponse between the 2 age groups (children – young adult) was 0.0% (2‑sided 95% CI: -2.0%, 2.2%). This information is presented in Table 11.
Table 11. Summary of geometric mean ratio for 50% neutralising titre and difference in percentages of participants with seroresponse – comparison of children 5 to 11 years of age (Study 3) to participants 16 to 25 years of age (Study 2) – participants without evidence of infection up to 1 month after Dose 2 – immunobridging subset – Phase 2/3 – evaluable immunogenicity population
| | COVID‑19 mRNA Vaccine | 5 to 11 years/ 16 to 25 years |
| 10 mcg/dose 5 to 11 years Na=264 | 30 mcg/dose 16 to 25 years Na=253 |
| | Time pointb | GMTc (95% CIc) | GMTc (95% CIc) | GMRd (95% CId) | Met immunobridging objectivee (Y/N) |
| Geometric mean 50% neutralising titref (GMTc) | 1 month after Dose 2 | 1 197.6 (1 106.1, 1 296.6) | 1 146.5 (1 045.5, 1 257.2) | 1.04 (0.93, 1.18) | Y |
| | Time pointb | ng (%) (95% CIh) | ng (%) (95% CIh) | Difference %i (95% CIj) | Met immunobridging objectivek (Y/N) |
| Seroresponse rate (%) for 50% neutralising titref | 1 month after Dose 2 | 262 (99.2) (97.3, 99.9) | 251 (99.2) (97.2, 99.9) | 0.0 (-2.0, 2.2) | Y |
Abbreviations: CI = confidence interval; GMR = geometric mean ratio; GMT = geometric mean titre; LLOQ = lower limit of quantitation; NAAT = nucleic acid amplification test; NT50 = 50% neutralising titre; SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2.
Note: Participants who had no serological or virological evidence (up to 1 month post-Dose 2 blood sample collection) of past SARS-CoV-2 infection (i.e. N-binding antibody [serum] negative at Dose 1 visit and 1 month after Dose 2, SARS-CoV-2 not detected by NAAT [nasal swab] at Dose 1 and Dose 2 visits, and negative NAAT (nasal swab) at any unscheduled visit up to 1 month after Dose 2 blood collection) and had no medical history of COVID-19 were included in the analysis.
Note: Seroresponse is defined as achieving a ≥ 4-fold rise from baseline (before Dose 1). If the baseline measurement is below the LLOQ, a post-vaccination assay result ≥ 4 × LLOQ is considered a seroresponse.
a. N = Number of participants with valid and determinate assay results before vaccination and at 1 month after Dose 2. These values are also the denominators used in the percentage calculations for seroresponse rates.
b. Protocol-specified timing for blood sample collection.
c. GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titres and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5 × LLOQ.
d. GMRs and 2-sided 95% CIs were calculated by exponentiating the mean difference of the logarithms of the titres (5 to 11 years of age minus 16 to 25 years of age) and the corresponding CI (based on the Student t distribution).
e. Immunobridging based on GMT is declared if the lower bound of the 2-sided 95% CI for the GMR is greater than 0.67 and the point estimate of the GMR is ≥ 0.8.
f. SARS-CoV-2 NT50 were determined using the SARS-CoV-2 mNeonGreen Virus Microneutralisation Assay. The assay uses a fluorescent reporter virus derived from the USA_WA1/2020 strain and virus neutralisation is read on Vero cell monolayers. The sample NT50 is defined as the reciprocal serum dilution at which 50% of the virus is neutralised.
g. n = Number of participants with seroresponse based on NT50 1 month after Dose 2.
h. Exact 2-sided CI based on the Clopper and Pearson method.
i. Difference in proportions, expressed as a percentage (5 to 11 years of age minus 16 to 25 years of age).
j. 2-Sided CI, based on the Miettinen and Nurminen method for the difference in proportions, expressed as a percentage.
k. Immunobridging based on seroresponse rate is declared if the lower bound of the 2-sided 95% CI for the seroresponse difference is greater than ‑10.0%.
Relative vaccine efficacy in participants 16 years of age and older – after booster dose
An interim efficacy analysis of Study 4, a placebo-controlled booster study performed in approximately 10 000 participants 16 years of age and older who were recruited from Study 2, evaluated confirmed COVID-19 cases accrued from at least 7 days after booster vaccination up to a data cut-off date of 5 October 2021, which represents a median of 2.5 months post-booster follow-up. The booster dose was administered 5 to 13 months (median 11 months) after the second dose. Vaccine efficacy of the Comirnaty booster dose after the primary series relative to the placebo booster group who only received the primary series dose was assessed.
The relative vaccine efficacy information for participants 16 years of age and older without prior evidence of SARS-CoV-2 infection is presented in Table 12. Relative vaccine efficacy in participants with or without evidence of prior SARS-CoV-2 infection was 94.6% (95% confidence interval of 88.5% to 97.9%), similar to that seen in those participants without evidence of prior infection. Primary COVID‑19 cases observed from 7 days after booster vaccination were 7 primary cases in the Comirnaty group, and 124 primary cases in the placebo group.
Table 12. Vaccine efficacy – First COVID-19 occurrence from 7 days after booster vaccination – participants 16 years of age and older without evidence of infection – evaluable efficacy population
| First COVID-19 occurrence from 7 days after booster dose in participants without evidence of prior SARS‑CoV‑2 infection* |
| | Comirnaty Na=4 695 Cases n1b Surveillance Timec (n2d) | Placebo Na=4 671 Cases n1b Surveillance Timec (n2d) | Relative Vaccine Efficacye % (95% CIf) |
| First COVID-19 occurrence from 7 days after booster vaccination | 6 0.823 (4 659) | 123 0.792 (4 614) | 95.3 (89.5, 98.3) |
Note: Confirmed cases were determined by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and at least 1 symptom consistent with COVID-19 (symptoms included: fever; new or increased cough; new or increased shortness of breath; chills; new or increased muscle pain; new loss of taste or smell; sore throat; diarrhoea; vomiting).
* Participants who had no serological or virological evidence (prior to 7 days after receipt of the booster vaccination) of past SARS-CoV-2 infection (i.e. N-binding antibody [serum] negative at Visit 1 and SARS‑CoV-2 not detected by NAAT [nasal swab] at Visit 1, and had a negative NAAT [nasal swab] at any unscheduled visit prior to 7 days after booster vaccination) were included in the analysis.
a. N = Number of participants in the specified group.
b. n1 = Number of participants meeting the endpoint definition.
c. Total surveillance time in 1 000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from 7 days after the booster vaccination to the end of the surveillance period.
d. n2 = Number of participants at risk for the endpoint.
e. Relative vaccine efficacy of the Comirnaty booster group relative to the placebo group (non-booster).
f. Two-sided confidence interval (CI) for relative vaccine efficacy is derived based on the Clopper and Pearson method adjusted for surveillance time.
Immunogenicity in children 5 to 11 years of age (i.e. 5 to less than 12 years of age) – after booster dose
A booster dose of Comirnaty was given to 401 randomly selected participants in Study 3. Effectiveness of a booster dose in ages 5 to 11 is inferred by immunogenicity. The immunogenicity of this was assessed through NT50 against the reference strain of SARS‑CoV‑2 (USA_WA1/2020). Analyses of NT50 1 month after the booster dose compared to before the booster dose demonstrated a substantial increase in GMTs in individuals 5 to 11 years of age who had no serological or virological evidence of past SARS‑CoV‑2 infection up to 1 month after the dose 2 and the booster dose. This analysis is summarised in Table 13.
Table 13. Summary of geometric mean titres – NT50 – participants without evidence of infection – phase 2/3 – immunogenicity set – 5 to 11 years of age – evaluable immunogenicity population
| | Sampling time pointa | |
| Assay | 1 month after booster dose (nb=67) GMTc (95% CIc) | 1 month after dose 2 (nb=96) GMTc (95% CIc) | 1 month after booster dose/ 1 month after dose 2 GMRd (95% CId) |
| SARS-CoV-2 neutralisation assay - NT50 (titre) | 2 720.9 (2 280.1, 3 247.0) | 1 253.9 (1 116.0, 1 408.9) | 2.17 (1.76, 2.68) |
Abbreviations: CI = confidence interval; GMR = geometric mean ratio; GMT = geometric mean titre; LLOQ = lower limit of quantitation; NT50 = 50% neutralising titre; SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2.
a. Protocol-specified timing for blood sample collection.
b. n = Number of participants with valid and determinate assay results for the specified assay at the given dose/sampling time point.
c. GMTs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the titres and the corresponding CIs (based on the Student t distribution). Assay results below the LLOQ were set to 0.5 × LLOQ.
d. GMRs and 2-sided 95% CIs were calculated by exponentiating the mean difference of the logarithms of the titres (1-Month Post–Booster Dose minus 1-Month Post–Dose 2) and the corresponding CI (based on the Student t distribution).
Immunogenicity of a booster dose following primary vaccination with another authorised COVID-19 vaccine
Effectiveness of a Comirnaty booster dose (30 mcg) in individuals who completed primary vaccination with another authorised COVID-19 vaccine (heterologous booster dose) is inferred from immunogenicity data from an independent National Institutes of Health (NIH) study phase 1/2 open‑label clinical trial (NCT04889209) conducted in the United States. In this study, adults (range 19 to 80 years of age) who had completed primary vaccination with Moderna 100 mcg 2‑dose series (N = 51, mean age 54±17), Janssen single dose (N = 53, mean age 48±14), or Comirnaty 30 mcg 2‑dose series (N = 50, mean age 50±18) at least 12 weeks prior to enrolment and who reported no history of SARS-CoV-2 infection received a booster dose of Comirnaty (30 mcg). The boost with Comirnaty induced a 36, 12, and 20 GMR‑fold rise in neutralising titres following the Janssen, Moderna, and Comirnaty primary doses, respectively.
Heterologous boosting with Comirnaty was also evaluated in the CoV-BOOST study (EudraCT 2021‑002175-19), a multicentre, randomised, controlled, phase 2 trial of third dose booster vaccination against COVID-19, in which 107 adult participants (median age 71 years of age, interquartile range 54 to 77 years of age) were randomised at least 70 days post 2 doses of AstraZeneca COVID-19 Vaccine. After the AstraZeneca COVID‑19 Vaccine primary series, pseudovirus (wild-type), neutralising antibody NT50 GMR-fold change increased 21.6‑fold with heterologous Comirnaty booster (n = 95).
Immunogenicity in pregnant participants and infants born to pregnant participants – after 2 doses with Comirnaty
Study 9 was a Phase 2/3 multinational, placebo-controlled, observer-blind study that enrolled pregnant participants 18 years of age and older to receive 2 doses of Comirnaty (n = 173) or placebo (n = 173). Pregnant participants received Dose 1 of Comirnaty at 24 to 34 weeks gestation and the majority (90.2%) received the second dose 19 to 23 days after Dose 1.
Descriptive immunogenicity analysis was performed in pregnant participants receiving Comirnaty in Study 9 compared to a comparator subset of nonpregnant participants from Study 2 evaluating the ratio of the neutralising GMT (GMR) 1 month after Dose 2. The evaluable immunogenicity population who received Comirnaty in the pregnant participants group in Study 9 (n = 111) and in nonpregnant participants in Study 2 (n = 114) had a median age of 30 years (range 18 to 44 years of age) and comprised of 37.8% vs 3.5% with a positive baseline SARS-CoV-2 status, respectively.
Among participants without prior evidence of SARS-CoV-2 infection up to 1 month after Dose 2, the observed SARS-CoV-2 50% neutralizing GMT 1 month after Dose 2 was lower in the pregnant participants (Study 9) when compared to nonpregnant female participants (Study 2) (the ratio of the GMT [GMR] was 0.67 (95% CI: 0.50, 0.90).
Among participants with or without prior evidence of SARS-CoV-2 infection up to 1 month after Dose 2, the model-adjusted GMT 1 month after Dose 2 was similar in the pregnant participants when compared to nonpregnant female participants (the model-adjusted ratio of the GMT [GMR] was 0.95 (95% CI: 0.69, 1.30). The model-adjusted GMT and GMR were calculated based on a regression model adjusting for age and baseline neutralizing titres.
Immunogenicity in immunocompromised participants (adults and children)
Study 10 is a Phase 2b, open-label study (n = 124) that enrolled immunocompromised participants 2 to < 18 years of age receiving immunomodulator therapy or who have undergone solid organ transplant (within the previous 3 months) and are on immunosuppression or who have undergone bone marrow or stem cell transplant at least 6 months prior to enrolment and in immunocompromised participants 18 years of age and older treated for non-small cell lung cancer (NSCLC) or chronic lymphocytic leukaemia (CLL), receiving haemodialysis for secondary to end‑stage renal disease, or receiving immunomodulator therapy for an autoimmune inflammatory disorder. Participants received 4 age‑appropriate doses of Comirnaty (3 mcg, 10 mcg, or 30 mcg); the first 2 doses separated by 21 days, with the third dose occurring 28 days after the second dose, followed by a fourth dose, 3 to 6 months after Dose 3.
Analysis of immunogenicity data at 1 month after Dose 3 (26 participants 2 to < 5 years of age, 56 participants 5 to < 12 years of age, 11 participants 12 to < 18 years of age, and 4 participants ≥ 18 years of age) and 1 month after Dose 4 (16 participants 2 to < 5 years of age, 31 participants 5 to < 12 years of age, 6 participants 12 to < 18 years of age, and 4 participants ≥ 18 years of age) in the evaluable immunogenicity population without evidence of prior infection demonstrated a vaccine‑elicited immune response. GMTs were observed to be substantially higher at 1 month after Dose 3 and further increased at 1 month after Dose 4 and remained high at 6 months after Dose 4 compared to levels observed before study vaccination across age groups and disease subsets.
Paediatric population
The licensing authority has deferred the obligation to submit the results of studies with Comirnaty in one or more subsets of the paediatric population in prevention of COVID-19 (see section 4.2 for information on paediatric use).