Moderna’s ‘Game-Changer’ Flu Vaccine Wins FDA Approval, With Annual Sales Potential of $1.6 Billion

The world’s first messenger RNA (mRNA) influenza vaccine, developed by Moderna, has been approved by the US Food and Drug Administration (FDA), raising expectations for the emergence of a blockbuster drug.

According to biopharmaceutical news outlet BioPharma Dive on the 18th local time, the FDA approved Moderna’s mRNA influenza vaccine mFlusiva for adults aged 50 and older earlier this month. For adults aged 65 and older, accelerated approval was granted contingent on the results of a confirmatory clinical trial.

Experts say the approval is an important achievement for Moderna, but that the company will face several hurdles before the vaccine can successfully establish itself in the market. The biggest variable, in particular, is when to select the influenza virus strains expected to circulate each year.

Currently, the World Health Organization (WHO) and the FDA determine vaccine strains 6 to 9 months before the influenza season. However, taking advantage of the rapid production of mRNA vaccines could allow that decision to be delayed until 2 months before the season. This could improve vaccine efficacy by enabling more accurate predictions of the circulating strains.

Miles Minter, an analyst at William Blair, noted, “If regulators do not change the current strain-selection process, the rapid production speed of mRNA vaccines could become useless.” Analysts say Moderna will need to bring about a “paradigm shift” among regulators to capitalize on this advantage.

In a phase 3 clinical trial in adults aged 50 and older, mFlusiva demonstrated a 26.6% higher relative vaccine efficacy than a standard-dose influenza vaccine. Nevertheless, skepticism about mRNA technology and a social climate that is unfavorable toward vaccines remain challenges that must be overcome.

The market expects mFlusiva to have difficulty generating substantial sales in the short term because it has already missed the contract cycle for this year’s influenza season. Minter said, “Meaningful sales will begin in 2027,” adding that the vaccine “has the potential to become a blockbuster drug by generating up to $1.1 billion in annual sales,” equivalent to approximately 165 billion won. That would represent about one-fifth of the current influenza vaccine market.

Despite these challenges, experts describe mFlusiva as a “game changer.” The expectation is that higher vaccine efficacy resulting from more accurate strain predictions could increase influenza vaccination rates, which currently remain low.

The approval is also expected to have a positive effect on Moderna’s development of a combined influenza and COVID-19 vaccine. The FDA previously paused its review of the combination vaccine after requesting additional efficacy data on its influenza component. Minter added, “It remains to be seen whether approval of the standalone influenza vaccine will reopen the regulatory path for the combination vaccine.”