Influenza, universal vaccine: the way for experimentation

The goal is a vaccine that protects against different strains and for a longer period

The clinical trial of a universal flu vaccine is underway in the USA, developed by researchers at the Vaccine Research Center of the National Institute of Allergy and Infectious Diseases (NIAID), a center that is part of the American National Institutes of Health (NIH) . The goal is to arrive at a vaccine that protects from a wide variety of strains and providing long-lasting immunity.

Volunteer enrollment began at Duke University in Durham, NC. Experts are working on a phase 1 study that will test the safety of the experimental vaccine – an mRNA vaccine known as ‘H1ssF-3928 mRNA-LNP’ – and its ability to induce immune responses.

Up to 50 healthy volunteers aged between 18 and 49 will be recruited. Three groups of 10 participants each will be vaccinated with doses of 10, 25 and 50 micrograms, respectively. After data evaluation, 10 additional participants will be enrolled to receive the dosage identified as optimal. The study will also include a group of participants who will receive a quadrivalent seasonal influenza vaccine, for a direct comparison of the immunogenicity and safety of the vaccine candidate with those available.


Why is there aspiration for a universal flu vaccine? While annual seasonal vaccines are invaluable in controlling the spread and severity of the flu, experts say, they don’t provide immunity against every viral strain. Each year, scientific predictions must be made of which are likely to be the most common in the following months and 3 or 4 selected to be included in the seasonal vaccine. Manufacturers therefore need time to produce and distribute it, and during this time the dominant strains of the virus can change in unexpected ways, potentially reducing effectiveness. An effective universal flu vaccine could eliminate these problems, protecting recipients against a wide variety of strains and ideally providing long-term lasting immunity.

“It would be a major public health achievement and could eliminate the need for both the annual development of seasonal flu vaccines and the need for patients to get an annual flu shot,” said Hugh Auchincloss, acting director of the Niaid.

“Furthermore – he added – some strains of the flu virus have significant pandemic potential. A universal flu vaccine could serve as an important line of defense against the spread of a future flu pandemic”.

“The universal flu vaccine is a chimera that has been chasing for years,” says virologist Fabrizio Pregliasco, who hopes positive data will arrive from clinical trials.

“Since I have been dealing with the flu, for more than 30 years, this universal vaccine has been a bit of the goal: to find an antigenic part that remains over time and does not change – the university professor explains to Adnkronos Salute Statale di Milano – But we haven’t succeeded yet. I believe that with the mRna we can get to this and certainly the universal vaccine simplifies the aspects of the annual checks and above all it also presumably allows a simplification of the vaccination scheme, no longer with a annual renewal requirement. With a tool of this type, one can aspire to “protection also against pandemic variants and therefore a strengthening of the population’s immune response”. So for Pregliasco “this option is welcome. We will see if the immunogenicity and safety data will comfort us”.