Spikevax® (COVID-19 Vaccine, mRNA) Efficacy & Safety

Spikevax (Original) was proven effective in adults starting 14 days after dose 2 of primary series¹*

COVE study results*: proven protection confirmed by RT-PCR¹.

Severe cases of COVID-19 were defined based on confirmed COVID-19 as per the primary efficacy endpoint case definition plus any of the following^1‡:

Clinical signs indicative of severe systemic illness, respiratory rate ≥30 breaths per minute, heart rate ≥125 beats per minute, SpO2 ≤93% on room air at sea level or PaO2/FIO2 <300 mm Hg; or respiratory failure or ARDS (defined as needing high-flow oxygen, non-invasive or mechanical ventilation, or ECMO), evidence of shock (systolic BP <90 mm Hg, diastolic BP <60 mm Hg or requiring vasopressors); or significant acute renal, hepatic, or neurologic dysfunction; or admission to an intensive care unit or death.

Primary endpoint subgroup analyses²

93.4%

effective against COVID-19^† at 4 months in adults aged 18-64 years studied¹

(n=10,661)

Primary endpoint subgroup analyses²

91.5%

effective against COVID-19^† at 4 months in adults aged ≥65 years studied¹

(n=3626)

Secondary endpoint²

98.2%

effective in preventing severe cases of COVID-19 in adults aged ≥18 years studied¹

(n=14,287)

Spikevax safety from clinical studies¹

Most commonly reported adverse reactions following administration of Spikevax (Original) or Moderna COVID-19 Vaccine, Bivalent containing the same amount of mRNA as the Spikevax 2023-2024 Formula (≥10%):

Adverse reactions	18-64 years of age	65 years and older
Pain at the injection site	up to 86.3%	up to 76.3%
Fatigue	up to 62.0%	up to 58.1%
Headache	up to 58.9%	up to 42.1%
Myalgia	up to 49.6%	up to 47.4%
Arthralgia	up to 41.9%	up to 39.5%
Chills	up to 40.3	up to 18.4%
Axillary swelling/tenderness	up to 24.8%	up to 14.3%
Nausea/vomiting	up to 16.7%	<10%

Spikevax clinical study design

Study	COVE^1-3	Bivalent^1-4
Objective	1:1 randomized, stratified, observer-blind, placebo-controlled study, comparing Spikevax (Original) primary series (mRNA 100 mcg per dose) vs placebo	Open-label, phase 2/3 study, comparing Moderna COVID-19 Vaccine, Bivalent (Original and Omicron BA.4/BA.5) booster (mRNA 50 mcg per dose) vs Spikevax (Original) booster (mRNA 50 mcg per dose)
Subjects	30,346 adults aged ≥18 years	819 adults aged ≥18 years^†
Primary endpoints	Safety and efficacy of Spikevax in preventing COVID-19 (confirmed by a RT-PCR test) Reactogenicity of 2 injections of Spikevax given 1 month apart	Safety and reactogenicity of Moderna COVID-19 Vaccine, Bivalent and Spikevax (Original)
Secondary endpoints	Prevention of severe COVID-19*	Noninferiority (on the basis of the difference in the percentage of participants with a seroresponse) against ancestral SARS-CoV-2 28 days after the second booster

Efficacy footnotes

*Median length of follow-up was 4 months. Data analysis prior to the emergence of the Delta and Omicron variants.

†Effectiveness is defined as preventing COVID-19, which was defined according to the following criteria: The participant must have experienced ≥2 of the following systemic symptoms: fever (≥38 °C/≥100.4 °F), chills, myalgia, headache, sore throat, new olfactory and taste disorder(s); or the participant must have experienced ≥1 of the following respiratory signs/symptoms: cough, shortness of breath or difficulty breathing, or clinical or radiographic evidence of pneumonia; and the participant must have ≥1 NP swab, nasal swab, or saliva sample (or respiratory sample, if hospitalized) positive for SARS-CoV-2 by RT-PCR.

‡Severe cases of COVID-19 were defined based on confirmed COVID-19 as per the primary efficacy endpoint case definition plus any 1 other item.

ARDS = acute respiratory distress syndrome

BP = blood pressure

COVID-19 = coronavirus disease 2019

ECMO = extracorporeal membrane oxygenation

FIO2 = fraction of inspired oxygen

NP = nasopharyngeal

PaO2 = partial pressure of oxygen; RT-PCR, reverse transcription polymerase chain reaction

SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2

SpO2 = oxygen saturation

Study design footnotes

*Severe cases of COVID-19 were defined based on confirmed COVID-19 as per the primary efficacy endpoint case definition, plus any of the following: Clinical signs indicative of severe systemic illness, respiratory rate ≥30 breaths per minute, heart rate ≥125 beats per minute, SpO2 ≤93% on room air at sea level or PaO2/FIO2 <300 mm Hg; or respiratory failure or ARDS (defined as needing high-flow oxygen, non-invasive or mechanical ventilation, or ECMO), evidence of shock (systolic BP <90 mm Hg, diastolic BP <60 mm Hg or requiring vasopressors); or significant acute renal, hepatic, or neurologic dysfunction; or admission to an intensive care unit or death.

†Subjects had previously received two 100-mcg doses of the Spikevax (Original) primary series and one 50-mcg dose Spikevax (Original) primary series booster ≥3 months before enrollment.

See above for abbreviations

Indication and Important Safety Information

Indication

SPIKEVAX (COVID-19 Vaccine, mRNA) is a vaccine indicated for active immunization to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) in individuals 12 years of age and older.

Important Safety Information

Contraindications

Do not administer SPIKEVAX to individuals with a known history of severe allergic reaction (e.g., anaphylaxis) to any component of SPIKEVAX or to individuals who had a severe allergic reaction (e.g., anaphylaxis) following a previous dose of a Moderna COVID-19 vaccine.

Warnings and Precautions

Management of Acute Allergic Reactions: Appropriate medical treatment must be immediately available to manage potential anaphylactic reactions following administration of SPIKEVAX.
Myocarditis and Pericarditis: Postmarketing data demonstrate increased risks of myocarditis and pericarditis, particularly within the first week following vaccination. The observed risk is highest in males 18 through 24 years of age.
Syncope (fainting): May occur in association with administration of injectable vaccines. Procedures should be in place to avoid injury from fainting.
Altered Immunocompetence: Immunocompromised persons, including individuals receiving immunosuppressive therapy, may have a diminished immune response to SPIKEVAX.
Limitations of Vaccine Effectiveness: SPIKEVAX may not protect all vaccine recipients.

Adverse Reactions

The most commonly reported (≥10%) adverse reactions following any dose in any indicated patient population were pain at the injection site, fatigue, headache, myalgia, chills, arthralgia, axillary swelling/tenderness, nausea/vomiting, and swelling at the injection site.

Reporting Adverse Events and Vaccine Administration Errors

To report suspected adverse reactions, contact ModernaTX, Inc. at 1-866-663-3762 or VAERS at 1-800-822-7967 or www.vaers.hhs.gov.

Please click for SPIKEVAX Full Prescribing Information.

References

Spikevax Prescribing Information. Moderna; 2024.
Baden, L. et al., "Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine," New England Journal of Medicine, Vol. 384(5), 2020. https://www.nejm.org/doi/full/10.1056/NEJMoa2035389
Moderna TX. Data on file.
Chalkias, S. et al., "A Bivalent Omicron-Containing Booster Vaccine against Covid-19," New England Journal of Medicine, Vol. 387(14), 2022. https://www.nejm.org/doi/full/10.1056/NEJMoa2208343

Stay up to date

Receive the latest information about all products from Moderna.

By submitting your information, you agree to Moderna's Terms and Conditions. You also acknowledge that your information will be processed in accordance with Moderna's Privacy Statement. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.