The current influenza vaccines only provide protection against a limited number of strains
Interim results from a recent study on influenza vaccine effectiveness (VE) estimations for the 2022/2023 season across six European countries has found VE to be only 27-44 per cent for influenza A and ≥ 50 per cent for influenza B, highlighting a longstanding unmet need for more effective seasonal influenza vaccines. The current influenza vaccines only provide protection against a limited number of strains, with the strains predicted to be dominant in the upcoming season selected for inclusion in the vaccines. However, research into universal influenza vaccines is gaining precedence, with several of these candidates entering clinical development, says GlobalData
Nusrat Haque, Infectious Disease Analyst, GlobalData comments, “The concept of a universal influenza vaccine is that it provides more durable protection against a wider variety of influenza strains than quadrivalent influenza vaccines, including unanticipated strains. In an ideal scenario this should eliminate the need to develop influenza vaccines on an annual basis, freeing up resources and saving patients from the inconvenience of annual vaccinations. Ultimately one of the biggest benefits of a universal influenza vaccine is that it could help to contain a potential pandemic.”
Some candidates have already reached clinical development. For example, Imutex’s FLU-v has demonstrated positive results in protecting against the intranasal challenge of wild-type (H1N1)pdm09 influenza A virus in a Phase IIb trial. In addition, Osivax’s OVX-836 provided protective efficacy in reducing influenza-like-illnesses, confirmed by polymerase chain reaction (PCR), in a Phase IIa trial, and is being evaluated in further Phase II studies.
Haque continues, “GlobalData estimates that in 2022 the lab-confirmed seasonal influenza mortality rate across all ages was 1.24 per 100,000 in the US. However, a universal vaccine that confers immunity against a wide range of influenza strains could drastically reduce the influenza-related hospitalization and mortality.”
The first mRNA-based universal vaccine, H1ssF-3928 mRNA-LNP, which was designed by the Vaccine Research Centre (VRC) of the National Institute of Allergy and Infectious Diseases (NIAID), has also recently advanced to Phase I clinical development in the US. The vaccine will be tested for safety and immunogenicity against an approved quadrivalent seasonal influenza vaccine.
Haque concludes, “The advantage of designing an mRNA-based universal influenza vaccine is that it could potentially be tested and produced quickly on a large scale, resulting in faster distribution to larger numbers of patients.”