A second COVID-19 vaccine has been granted full approval by the Food and Drug Administration (FDA).

Spikevax, also known as the Moderna COVID-19 vaccine, has been approved for active immunization to prevent COVID-19 caused by SARS-CoV-2 in individuals 18 years of age and older. The vaccine is administered intramuscularly as a series of 2 doses (0.5mL each) 1 month apart. The product is supplied in multiple-dose vials containing either 5.5mL or 7.5mL. 

The approval was based on data that supported the Emergency Use Authorization (EUA) of the Moderna COVID-19 vaccine, as well as updated safety and efficacy analyses. Findings from an ongoing randomized, placebo-controlled, observer-blind phase 3 trial showed 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.

Among 14,287 vaccine recipients, there were 55 cases of COVID-19, while in the placebo group, which included 14,164 recipients, there were 744 cases. Results also showed the vaccine was 98.2% (95% CI, 92.8-99.6) effective at preventing severe disease. These analyses were conducted prior to the emergence of the Omicron variant.

The safety analysis included 15,184 vaccine recipients and 15,162 placebo recipients; participants were followed for safety outcomes for at least 4 months after the second dose. The most common adverse reactions reported were pain at the injection site, fatigue, headache, myalgia, chills, arthralgia, nausea/vomiting, axillary swelling/tenderness, fever, swelling at the injection site, and erythema at the injection site.

“The FDA’s medical and scientific experts conducted a thorough evaluation of the scientific data and information included in the application pertaining to the safety, effectiveness, and manufacturing quality of Spikevax,” said Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research. “The public can be assured that this vaccine was approved in keeping with the FDA’s rigorous scientific standards.”

A review of postauthorization safety surveillance data showed that the vaccine was associated with an increased risk of myocarditis particularly 7 days following the second dose. The risk was observed to be highest among males 18 to 24 years old. Most of these cases resolved with conservative management, though some required intensive care support.

The FDA is requiring that Moderna conduct postmarketing studies to further assess the risk of myocarditis and pericarditis following vaccination with Spikevax. The Company also plans to conduct additional safety studies to evaluate pregnancy-related outcomes.

Spikevax has the same formulation as the Moderna COVID-19 vaccine, which continues to be authorized for emergency use for individuals 18 years of age and older as a third primary series dose (100µg dose level) for individuals with certain immunocompromising conditions, and as a single booster dose (50µg dose level) at least 5 months after completing a primary series of the vaccine.

The Moderna COVID-19 vaccine is also authorized for use as a heterologous single booster dose for individuals 18 years of age and older following completion of primary vaccination with a different available COVID-19 vaccine.


  1. FDA takes key action by approving second COVID-19 vaccine. News release. January 31, 2022. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-takes-key-action-approving-second-covid-19-vaccine
  2. Spikevax. Package insert. Moderna; 2022. Accessed January 31, 2022. https://www.fda.gov/media/155675/download