In recent weeks, the COVID-19 vaccine arsenal has grown more robust. Here’s what you need to know:
Variant-specific boosters. On September 1, the Advisory Committee on Immunization Practices (ACIP) adopted a recommendation for a booster of either a new bivalent Pfizer-BioNTech COVID-19 vaccine (for individuals ages 12 years and older) or bivalent Moderna COVID-19 vaccine (for individuals ages 18 years and older) at least 2 months after receipt of a primary series or prior monovalent booster dose. Both bivalent vaccines were recently approved by the Food and Drug Administration (FDA) under an Emergency Use Authorization (EUA) and offer protection against one of the more common circulating strains of SARS-COV-2 (BA.1) while boosting immunity to the original strain. Both options are approved only as booster shots, not as an original COVID vaccine series.1
Novavax vaccine. This summer, the FDA issued an EUA for the Novavax COVID-19 vaccine in adults and a later EUA for adolescents (ages 12 to 17 years).2 Novavax is the fourth vaccine available to combat COVID-19 infection. This newest addition to the COVID armamentarium consists of coronavirus protein subunits, produced using recombinant technology, and a matrix adjuvant. The primary series consists of 2 doses administered at least 3 weeks apart.3,4
A few caveats: The Novavax vaccine comes in 10-dose vials, which should be kept refrigerated until use. Once the first dose is used, the vial should be discarded after 6 hours. This may present some scheduling and logistical issues. Also, the Novavax vaccine is not currently approved for use in children younger than 12 years, or as a booster to other vaccines.3,4
The effectiveness and safety of the Novavax vaccine appears to be comparable to that of the other vaccines approved to date, although measuring vaccine effectiveness is a tricky business given the rapid mutation of the virus and changing dominant strains.3,4 The Novavax vaccine’s efficacy against currently circulating Omicron variants of the virus (eg, BA.2.12.1, BA.4, BA.5) remains to be determined.
As far as safety, preliminary studies indicate that Novavax may be associated with rare cases of myocarditis.3,4 Myocarditis can result from the COVID infection itself at an overall rate of 1 to 2 per 1000, which is 16 times the rate in adults without COVID.5
Could it provide reassurance to the hesitant? The Novavax COVID vaccine was developed using a vaccine platform and production process similar to that of other commonly administered vaccines, such as hepatitis B vaccine and human papillomavirus vaccine. This may make it an appealing option for patients who have shown hesitancy toward new vaccine technologies.
And, of course, there are the Pfizer and Moderna vaccines. Currently, there are 2 vaccines approved under the normal licensing process for adults, both of which are mRNA-based vaccines: Pfizer/BioNTech (Comirnaty) for those ages 12 years and older and Moderna (Spikevax) for those ages 18 and older. A third COVID vaccine option is manufactured by Johnson & Johnson (Janssen) and uses an adenovirus platform. The FDA revised its EUA in May to limit its use.6 The Johnson & Johnson vaccine has been associated with rare but serious reactions called thrombosis with thrombocytopenia. ACIP recommends all other vaccines in preference to the Johnson & Johnson vaccine.
For more on COVID vaccination for patients of all ages, see: www.cdc.gov/vaccines/covid-19/downloads/COVID-19-immunization-schedule-ages-6months-older.pdf