FDA Seeks to Simplify COVID Vaccination Program

A more harmonized formula and schedule for administering anti-COVID-19 vaccines gained strong support from FDA’s expert advisory panel last week, with agreement on the need to reduce confusion over which shot to take and when in order to increase vaccination rates among both adults and children in the US. The 21 members of FDA’s Vaccine and Related Biological Products Advisory Committee (VRBAC) voted unanimously for a more simplified approach, setting the stage for the agency to authorize a common bivalent shot for all patients that targets the original COVID strain and the Omicron subvariants. The new program would end use of Pfizer and Moderna monovalent vaccines that only target the original COVID strain.

FDA received less support for setting a schedule for annual vaccination against COVID, as the advisors expressed uncertainty about the effectiveness of the current shots and questioned what time during the year would be best for a national COVID vaccination campaign. Several panel members urged additional research on the effectiveness of the new formulations on frequently changing variants and the possible need for different vaccination schedules for both children and older adults with health impairments. The experts called on FDA to provide additional data on vaccine effectiveness and timing to better determine whether all patients would need an annual shot.

The strategy to set a common formula for anti-COVID vaccines across the country aims to increase vaccination rates overall. New data from the Centers for Disease Control and Prevention (CDC) indicates that less than half of all older Americans (over age 65) have received the updated booster, and that vaccination rates are a meager 10% for children under age 4. The hope is that a shift away from differing vaccine compositions and varying immunization schedules, along with clearer alignment between US and European vaccination recommendations, will encourage more people to get such protection.

Pfizer, Moderna, and Novavax reported to VERBAC on efforts underway to produce reformulated bivalent vaccines and supported the plan to establish a common formulation for all manufacturers of the adopted shot to simplify vaccination recommendations and reduce patient uncertainty over effectiveness and safety of vaccines from different companies. The manufacturers emphasized the need for specifics from FDA on the process for updating vaccine strains, including the timing, process, and methodology for producing a data package for new licensure. While such filings are expected to include new preclinical and manufacturing data, sponsors opposed requirements for additional clinical trials, indicating that it will be more productive to assess post-authorization real-world data to confirm effectiveness.

FDA officials proposed to meet with the advisory panel in May or June to decide on which COVID strain to target in vaccines for later this year, anticipating a fast reformulation by manufacturers of mRNA vaccines. But Novavax officials indicated that it might need to identify the strain earlier, probably in March, to produce a new vaccine by fall with its more traditional vaccine production process. All three shot manufacturers reported that they were already shifting to use prefilled syringes and single-dose vials, which are important for physicians, clinics, and pharmacies planning to administer the new vaccines more widely in the wake of reduced federal government involvement in the program.

A related question is whether FDA will ask manufacturers to produce combination influenza/COVID vaccines to further simplify annual vaccination programs. The three firms reported that they are already studying such combination shots, but any shift toward such products will involve much further assessment of the need for and effectiveness of annual COVID vaccines or combination products.

While advisory committee experts and officials from FDA and other health agencies acknowledged the value of utilizing mRNA platforms to produce anti-COVID vaccines so quickly and effectively at the start of the pandemic, some panel members called for further research on how well the new formulations provide long-term protection and avoid safety issues, urging continued examination of whether more traditional vaccine production methods may have broader benefits moving forward. In its presentation, Novavax presented data indicating a “robust breadth of immunity” and strong manufacturing consistency for its more recently approved preventive.

In concluding the meeting, Peter Marks, director of the Center forBiologics Evaluation and Research (CBER), reiterated the need for a “data-driven approach” to achieve a vaccine regimen that is as simple as possible. But he also noted the importance of monitoring vaccine safety and assessing product effectiveness in shifting to a next generation of COVID vaccines able to provide “greater depth of protection.”