Moderna announced Tuesday that the first participants have been vaccinated in a Phase 3 study of its influenza (flu) vaccine, which is based on mRNA technology used in its COVID-19 vaccine.

The vaccine, mRNA-1010, encodes for hemagglutinin (HA) glycoproteins of the four influenza strains recommended by the World Health Organization (WHO) for the prevention of influenza.

Flu epidemics generally occur in the winter and some years can place a heavy burden on healthcare systems, with as many as 3 million to 5 million severe cases and, at its worst, as many as 650,000 deaths, according to WHO.

The trial is expected to enroll approximately 6,000 adults in countries in the southern hemisphere. It is a randomized, observer-blind study that is meant to evaluate the safety and immunological efficacy of mRNA-1010 in comparison to a licensed seasonal influenza vaccine in adults 18 years and older. Participants will be randomly assigned on a 1:1 ratio to receive either a single dose of mRNA-1010 or a single dose of a licensed seasonal influenza vaccine as a comparator.

The company aims to run a confirmatory efficacy study for mRNA-1010 as early as the 2022/2023 northern hemisphere influenza season.

“mRNA-1010 is the first of several influenza vaccine candidates we are developing with the aim of iteratively improving traditional vaccines by inducing broad and robust immune responses,” Moderna CEO Stéphane Bancel said in a release. “We believe our mRNA platform, with the flexibility and speed of our manufacturing process, is well-positioned to address the significant unmet need in seasonal flu.

Moderna was founded 12 years ago and became well-known two years ago with the development of its SARS-CoV2 mRNA vaccine. It was the second mRNA vaccine ever to be produced and was approved by the US Food and Drug Administration. The first mRNA vaccine was developed by Pfizer and BioNTech.

Moderna is currently engaged in four Phase III studies, it said, including its SARS-CoV-2 booster, RSV, seasonal flu and CMV vaccine candidates.

“Beginning in the fall of 2022, the company’s Phase III pipeline could lead to three respiratory commercial launches over the next two to three years,” Bancel said.

Image Credits: Moderna, KEYSTONE/Gaetan Bally.