Spikevax

Efficacy of Spikevax Two-Dose Primary Series in Participants 18 Years of Age and Older

• The approval was based on data from the ongoing randomized, placebo-controlled, observer-blind phase 3 clinical trial (Study 1) which evaluated the efficacy, safety, and immunogenicity of Spikevax in adults 18 years of age and older in the US. The study excluded patients who were immunocompromised and with a known history of SARS-CoV-2 infection. A total of 30,415 patients were randomly assigned equally to receive 2 doses of Spikevax or saline placebo 1 month apart.

• Efficacy Against COVID-19

• Spikevax was 93.2% (95% CI, 91.0-94.8) effective at preventing COVID-19 in participants 18 years of age and older starting 14 days after the second dose. There were 55 cases of COVID-19 in the Spikevax group and 744 cases in the placebo group. 

• Spikevax was 98.2% (95% CI, 92.8-99.6) effective at preventing severe disease. There were 2 cases of severe COVID-19 in the Spikevax group and 106 cases in the placebo group.

Effectiveness of Spikevax Two-Dose Primary Series in Participants 12 Years Through 17 Years of Age

• The randomized, placebo-controlled, observer-blind phase 3 study (Study 3) evaluated the safety, reactogenicity, and effectiveness of 2 doses of Spikevax in a total of 3733 patients 12 to 17 years of age in the United States. Patients were randomly assigned 2:1 to receive 2 doses of Spikevax or placebo 1 month apart.

• An analysis was conducted of SARS-CoV-2 50% neutralizing titers and seroresponse rates 28 days after Dose 2 in a subset of patients 12 years through 17 years of age in Study 3 and patients 18 years through 25 years of age in Study 1 who had no immunologic or virologic evidence of prior SARS-CoV-2 at baseline.

• Results showed that the immune responses (assessed by geometric mean 50% neutralizing titers and seroresponse rates) of patients 12 to 17 years of age were noninferior to that observed in patients 18 to 25 years of age.

• Spikevax was 100% effective for COVID-19 Case Definition 1, which was the patient must have experienced at least 2 systemic symptoms (fever, chills, myalgia, headache, sore throat, new olfactory, and taste disorder[s]); or the patient must have at least 1 respiratory signs/symptoms; and the patient must have at least 1 NP swab, nasal swab, or saliva sample positive for SARS-CoV-2 by RT-PCR.

• Spikevax was 89.9% effective for COVID-19 Case Definition 2, which was the presence of at least 1 symptom from a list of COVID-19 symptoms and a positive NP swab or saliva sample for SARS-CoV-2 by RT-PCR.

Immunogenicity of a Single Dose of Moderna COVID-19 Vaccine, Bivalent in COVID19 Vaccine-Naïve Individuals with Evidence of Prior SARS-CoV-2 Infection

• In an open-label phase of Study 3, COVID-19 vaccine-naïve patients 12 to 17 years of age received a single dose of Moderna COVID-19 Vaccine, Bivalent (50mcg mRNA). The immunogenicity subset included 246 patients, of which 99.6% had evidence of prior SARS-CoV-2 infection at baseline.

• The primary immunogenicity analysis population included 245 patients 12 to 17 years of age with evidence of SARS-CoV-2 infection at baseline from Study 3 and 296 patients 18 to 25 years of age without evidence of prior SARS-CoV-2 infection at baseline from Study 1 who received 2 doses of Spikevax (100mcg mRNA per dose).

• According to primary immunogenicity analyses of the GMC ratio, results showed that the single dose in Study 3 met the predefined success criteria for superiority against Omicron BA.4/BA.5 and noninferiority against the Original strain.

Immunogenicity of Spikevax Administered as a First Booster Dose Following a Spikevax Primary Series in Participants 18 Years of Age and Older

• Effectiveness of a booster dose of Spikevax was based on assessment of neutralizing antibody geometric mean concentration (GMC) against a pseudovirus expressing the original SARS-CoV-2 Spike protein (D614G).

• In an open-label booster dose phase of Study 1, the primary immunogenicity analysis population included 682 patients 18 years of age and older who received a single booster dose of Spikevax (50 mcg mRNA) at least 6 months after completion of the primary series of Spikevax (two doses of 100 mcg mRNA 1 month apart).

• Results showed that the booster dose in Study 1 met the success criteria for GMC ratio and difference in seroresponse rates when compared with the primary series. The booster dose seroresponse rate was 98.4%. Seroresponse rate was defined as at least a 4-fold rise relative to the pre-booster concentration.

Immunogenicity of Spikevax Booster Dose Following Spikevax Primary Series in Participants 12 Years Through 17 Years of Age

• In an open-label booster dose phase of Study 3, participants who were 12 years through 17 years of age at the time of first dose of a primary series received a single booster dose of Spikevax (50mcg mRNA) at least 5 months (range 2.1 to 16.9) after completion of the primary series (2 doses 1 month apart).

• The primary immunogenicity analysis population included 264 booster dose participants in Study 3 and a random subset of 295 participants 18 years through 25 years of age from Study 1 who received two doses of Spikevax 1 month apart.

• Results showed that the booster dose in Study 3 met the success criteria for GMC ratio and difference in seroresponse rates when compared with the primary series. The booster dose seroresponse rate was 96.6%. Seroresponse rate was defined as at least a 4-fold rise relative to the pre-booster concentration.

Immunogenicity of Moderna COVID-19 Vaccine, Bivalent Administered as a Second Booster Dose

• The open-label phase 2/3 study (Study 5) compared the immunogenicity of a second booster dose of Moderna COVID-19 Vaccine, Bivalent (50mcg mRNA) to a second booster dose of Spikevax (50mg mRNA) in patients 18 years of age and older who previously received a primary series and a first booster dose with Spikevax at least 3 months prior.

• The primary immunogenicity analysis population included 209 participants who received a booster dose of Moderna COVID-19 Vaccine, Bivalent and 259 participants who received a booster dose of Spikevax. 

• Analyses of GMTs met predefined success criteria for superiority against Omicron BA.4/BA.5 and noninferiority against the Original strain.