Encouraging Results Emerge from Phase 1/2 Study of mRNA-Based Influenza and COVID-19 Combo Vaccines

Teen giving thumbs up after getting vaccinated and showing bandage on her arm: © Yashvi- stock.adobe.com

(Editor's note: A version of this article originally appeared on our sister publication's website, Contemporary Pediatrics: https://www.contemporarypediatrics.com/view/combination-influenza-and-covid-19-vaccine-program-demonstrates-positive-phase-results)

Promising outcomes have been unveiled in a phase 1/2 investigation involving mRNA-based combination vaccines targeting both influenza and COVID-19, as per a press release jointly issued by Pfizer and BioNTech.

The phase 1/2 study, registered under NCT05596734, focused on evaluating the safety, immunogenicity, and tolerability of these combination vaccine candidates in a cohort of healthy adults aged between 18 and 64. This ongoing clinical trial has confirmed that the combination formulations exhibit a consistent safety profile that aligns with Pfizer's COVID-19 vaccine.

Within the trial, lead formulations successfully triggered immunogenic responses. These findings unveiled point estimates for Geometric Mean Titer (GMT) ratios that closely adhered to the criteria stipulated for regulatory approval of vaccines designed to combat influenza and SARS-CoV-2 strains. A comparison was drawn between the companies' Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine and the vaccine candidates administered during the same clinical trial session.

Pfizer reported, "Data derived from the trial unequivocally attested to the robust immune responses of our lead formulations against influenza A, influenza B, and SARS-CoV-2 strains."

This vaccine exhibits the potential to mitigate the impact of respiratory ailments through a solitary injection, thus streamlining immunization procedures for healthcare providers, patients, and medical systems worldwide," conveyed Annaliesa Anderson, PhD, FAAM, who serves as the Senior Vice President and Head of Vaccine Research and Development at Pfizer. "mRNA-based vaccines have consistently demonstrated their capability to stimulate potent antibody and T-cell responses, and we eagerly anticipate embarking on phase 3 clinical development. These findings represent a significant milestone in our quest to offer a comprehensive array of combination respiratory vaccines."

The point estimates for GMT ratios associated with all matching influenza vaccine strains, when linked to the lead formulations, exhibited ratios greater than 1 in relation to a licensed quadrivalent influenza vaccine (QIV), which was co-administered with the Pfizer-BioNTech COVID-19 vaccine, as disclosed in the press release.

It's worth noting that the combination vaccine candidate targeting both influenza and COVID-19 previously secured Fast Track Designation from the FDA. In the ensuing months, a pivotal phase 3 trial will be initiated, which will delve deeper into the lead formulations' potential.

Reference
Pfizer and BioNTech Unveil Favorable Findings in mRNA-Based Combo Vaccine Program Targeting Influenza and COVID-19. Pfizer. Press Release. October 26, 2023. Accessed October 26, 2023. [https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-announce-positive-topline-data-mrna?cid=em_PfizerNewsroomAlert&ttype=em]