No immunological interference or concerns about safety when seasonal quadrivalent influenza vaccine is co-administered with a COVID-19 mRNA-1273 booster vaccine in adults: A randomized trial

ABSTRACT

The objective of the study was to assess the safety and immunogenicity of mRNA-1273 COVID-19 booster vaccination when co-administered with an egg-based standard dose seasonal quadrivalent influenza vaccine (QIV). This was a phase 3, randomized, open-label study. Eligible adults aged ≥ 18 years were randomly assigned (1:1) to receive mRNA-1273 (50 µg) booster vaccination and QIV 2 weeks apart (Seq group) or concomitantly (Coad group). Primary objectives were non-inferiority of haemagglutinin inhibition (HI) and anti-Spike protein antibody responses in the Coad compared to Seq group. 497/498 participants were randomized and vaccinated in the Seq/Coad groups, respectively. The adjusted geometric mean titer/concentration ratios (95% confidence intervals) (Seq/Coad) for HI antibodies were 1.02 (0.89–1.18) for A/H1N1, 0.93 (0.82–1.05) for A/H3N2, 1.00 (0.89–1.14] for B/Victoria, and 1.04 (0.93–1.17) for B/Yamagata; and 0.98 (0.84–1.13) for anti-Spike antibodies, thus meeting the protocol-specified non-inferiority criteria. The most frequently reported adverse events in both groups were pain at the injection site and myalgia. The 2 groups were similar in terms of the overall frequency, intensity, and duration of adverse events. In conclusion, co-administration of mRNA-1273 booster vaccine with QIV in adults was immunologically non-inferior to sequential administration. Safety and reactogenicity profiles were similar in both groups (clinicaltrials.gov NCT05047770).

Plain Language Summary

What is the context?

• Updated booster shots against COVID-19 disease are likely to offer more protection as the virus is changing over time.

• It is important for doctors, other healthcare providers and patients to know whether COVID-19 booster vaccines can be given at the same time as other vaccines recommended for adults.

What is new?

• The results of our study showed that an mRNA-based COVID-19 booster vaccine could be given at the same time as the seasonal influenza vaccine.

• When given together, both vaccines led to immune responses and had side effects that were similar to those observed when they were given at separate times.

What is the impact?

• The potential benefits of administering more than 1 vaccine during a healthcare visit include improved coverage and a reduced number of doctor visits needed to receive all vaccines.

• Co-administration of COVID-19 booster vaccines and influenza vaccines could be an attractive option for patients and healthcare professionals.