Monday, August 1, 2022

Will vaccine hesitant US adults accept a more traditional COVID-19 vaccine?

 - Jennifer Middleton, MD, MPH

Earlier this month, the United States (US) Food and Drug Administration (FDA) issued an Emergency Use Authorization (EUA) for Novavax for adults aged 18 and older:

The Novavax COVID-19 Vaccine, Adjuvanted is administered as a two-dose primary series, three weeks apart. The vaccine contains the SARS-CoV-2 spike protein and Matrix-M adjuvant. Adjuvants are incorporated into some vaccines to enhance the immune response of the vaccinated individual.

This technology is similar to more traditional vaccines, such as the influenza vaccine, and differs from the available mRNA COVID-19 vaccines from Pfizer and Moderna. It's currently authorized as a 2 shot series, with doses given 3 weeks apart. In the clinical trial data of 25,500 participants submitted to the FDA, Novavax reported that 2 doses of their vaccine were, overall, "90.4% effective in preventing mild, moderate or severe the subset of participants 65 years of age and older, the vaccine was 78.6% effective." Several countries worldwide who have previously authorized the Novavax vaccine offer a booster 5 months after the 2nd shot, and Novavax is reportedly pursuing authorization in the US for both that booster as well as administration to adolescents aged 12-17. They are also testing boosters with protection against the omicron strain. Although Novavax was part of the US government's Operation Warp Speed in 2020, the company suffered "developing and manufacturing setbacks" as a smaller start-up which put it behind Pfizer and Modera in the race to an EUA. 

The speed of the mRNA vaccines' development, along with the newness of their technology, led some people to question their short- and long-term safety. Given this reluctance regarding mRNA vaccines, Novavax, which "has no genetic material, only proteins," may be a more comfortable option for some patients. Approximately 10% of the adult population in the US has yet to receive a first dose of any of the COVID-19 vaccines, and increasing vaccine uptake may help slow the development of new variants

As noted on the blog last year, helpful resources to discuss vaccine hesitancy with patients include these resources and talking points from the US Centers for Disease Control and Prevention (CDC) along with this article on "Helping Patients Make Healthy Decisions on COVID-19" found in the AFP By Topic on Coronavirus Disease 2019 (COVID-19).