The
mRNA-1273 (
Moderna) COVID-19 vaccine is a
lipid nanoparticle-encapsulated,
nucleoside-modified
mRNA vaccine encoding the stabilized prefusion spike
glycoprotein of SARS-CoV-2, the virus that causes
COVID-19. During December 2020, the
vaccine was granted Emergency Use Authorization (EUA) by the Food and Drug Administration (FDA), and the Advisory Committee on Immunization Practices (ACIP) issued an interim recommendation for use among persons aged ≥18 years (1), which was adopted by CDC. During December 19, 2020-January 30, 2022, approximately 204 million doses of
Moderna COVID-19 vaccine were administered in the United States (2) as a primary series of 2 intramuscular doses (100 μg [0.5 mL] each) 4 weeks apart. On January 31, 2022, FDA approved a Biologics License Application (BLA) for use of the
Moderna COVID-19 vaccine (
Spikevax, ModernaTX, Inc.) in persons aged ≥18 years (3). On February 4, 2022, the ACIP
COVID-19 Vaccines Work Group conclusions regarding recommendations for the use of the
Moderna COVID-19 vaccine were presented to ACIP at a public meeting. The Work Group's deliberations were based on the Evidence to Recommendation (EtR) Framework,* which incorporates the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach† to rank evidence quality. In addition to initial clinical trial data, ACIP considered new information gathered in the 12 months since issuance of the interim recommendations, including additional follow-up time in the clinical trial, real-world
vaccine effectiveness studies, and postauthorization
vaccine safety monitoring. ACIP also considered comparisons of
mRNA vaccine effectiveness and safety in real-world settings when first doses were administered 8 weeks apart instead of the original intervals used in clinical trials (3 weeks for
BNT162b2 [Pfizer-BioNTech]
COVID-19 vaccine and 4 weeks for
Moderna COVID-19 vaccine). Based on this evidence, CDC has provided guidance that an 8-week interval might be optimal for some adolescents and adults. The additional information gathered since the issuance of the interim recommendations increased certainty that the benefits of preventing symptomatic and asymptomatic
SARS-CoV-2 infection, hospitalization, and death outweigh
vaccine-associated risks of the
Moderna COVID-19 vaccine. On February 4, 2022, ACIP modified its interim recommendation to a standard recommendation§ for use of the fully licensed
Moderna COVID-19 vaccine in persons aged ≥18 years.