JCVI Recommends CSL Seqirus' Aujemflu for 2027/28 UK Flu Season, Moderna's mRNA Vaccine Deferred
Key Insights
The JCVI has recommended CSL Seqirus (search)' trivalent adjuvanted cell-cultured influenza (search) vaccine (aIIVc), Aujemflu (search), for adults aged 65+ and at-risk adults aged 50–64 in the 2027/28 UK flu programme.
Moderna's quadrivalent mRNA influenza (search) vaccine (mRNA-1010) was also reviewed but is unlikely to be available for procurement in the 2027/28 season and will be considered for future seasons.
The 2025/26 flu season saw 3,798 influenza (search)-attributable deaths, lower than recent seasons, with vaccines retaining meaningful effectiveness despite a drifted A(H3N2) strain.
The Joint Committee on Vaccination and Immunisation (JCVI) has recommended that Aujemflu (search), a new trivalent adjuvanted inactivated cell-cultured influenza (search) vaccine (aIIVc) from CSL Seqirus (search), can be considered alongside existing flu vaccines for the 2027/28 UK influenza vaccination programme. The recommendation applies to adults aged 65 and over, as well as adults aged 50 to 64 in a clinical risk group.
The Medicines and Healthcare products Regulatory Agency (MHRA) granted marketing authorisation for Aujemflu (search) on 4 June 2026, for the protection of adults aged 50 and over against influenza (search). The JCVI reviewed the product at its meeting on the same date, following an influenza sub-committee meeting on 30 May 2026.
Moderna's mRNA vaccine deferred
The JCVI also reviewed a second new product — Moderna's quadrivalent mRNA influenza (search) vaccine (mRNA-1010). However, the committee noted that the vaccine was unlikely to be available for procurement in the 2027/28 season and would be considered for future seasons instead, subject to market authorisation and availability.
2025/26 season: early onset, drifted strain, lower mortality
The 2025 to 2026 influenza (search) season was characterised by an unusually early onset of activity starting in the second half of October 2025, driven by rising influenza A(H3N2) activity in children and young adults. Activity peaked around the second week of December 2025 and declined thereafter, returning early to baseline levels.
The season was dominated by a drifted influenza (search) A(H3N2) strain (subclade K, J.2.4.1) compared with the WHO-designated vaccine strain. Despite this antigenic mismatch, the vaccines used in the programme retained "meaningful effectiveness across age groups," the JCVI stated, with higher vaccine effectiveness observed in children compared with adults.
The estimated number of influenza (search)-attributable excess deaths was 3,798 in 2025/26, notably lower than 9,740 in 2024/25, 4,431 in 2023/24, and 14,378 in 2022/23.
The schools' vaccine programme, which started in September 2025, had its strongest start on record, helping to reduce influenza (search) transmission to the wider population including adults. The move to start the adult vaccine programme (except for pregnant women) in October 2025 concentrated protection around the early peak of the infection wave.
Vaccine preferences for 2027/28
For adults aged 65 years and over, the JCVI advises the use of aIIVc, adjuvanted inactivated influenza (search) vaccine (aIIV), inactivated influenza cell-cultured vaccine (IIVc), high-dose inactivated influenza vaccine (IIV-HD), or recombinant inactivated influenza vaccine (IIVr) as preferred options. The committee strongly advises against the use of inactivated influenza egg-cultured vaccine (IIVe) in this age group.
The JCVI acknowledged that relevant comparative data on aIIV, IIVc, IIV-HD and IIVr is limited, and the level of uncertainty — including the lack of head-to-head studies — is "considered too great to allow for a preferential recommendation between these four vaccines at the current time." Based on immunogenicity data, aIIVc has now been added to this group.
For at-risk adults aged 18 to 64 years, IIVc and IIVr are the vaccines of choice, with aIIVc, aIIV and IIV-HD also available as preferred options for those aged 50 to 64. The JCVI noted growing evidence from the UK programme that IIVr is more effective than IIVe in adults under 65, and highlighted the "real concern" of egg adaptation, particularly against A(H3N2) strains which are "a more virulent influenza (search) subtype in terms of morbidity and mortality."
For children aged 2 to under 18 years, the live attenuated influenza (search) vaccine (LAIV) remains the vaccine of choice. In the 2025/26 season, vaccine effectiveness against hospitalisation associated with the drifted A(H3N2) strain was significantly higher for LAIV compared with IIVc.
Call for real-world evidence
The JCVI emphasised the need for further comparative data, "preferably from the same country over multiple seasons and with laboratory-confirmed influenza (search) endpoints," to support consideration of the relative effectiveness of influenza vaccines available in the UK. The committee stated it "would like to see all the available vaccines, which it has advised in preference to standard egg-based vaccines, used in the UK so they can be rigorously evaluated through the programme," while acknowledging this is subject to NHS negotiations.
The JCVI also noted that improvements in data systems have enabled better vaccine effectiveness estimates with hospitalisation as a clinical endpoint, and stressed the importance of maximising influenza (search) A subtyping to support future evaluations.