The FDA rejected Moderna's application to review a new flu vaccine based on mRNA technology.[1] Moderna made the announcement Tuesday, publishing a letter from Vinay Prasad, head of the FDA's Division of Biologics.[1] The controversy is over which existing flu vaccine Moderna should have used as a control when testing the effectiveness of the new vaccine.[1] The new vaccine uses the same mRNA technology as Moderna's COVID-19 vaccine.[1] Moderna CEO Stéphane Bancel said the decision does not support the common goal of strengthening US leadership in innovative medicines.[1] The decision may raise concerns about the FDA's stance toward pharmaceutical companies and the Trump administration's policy toward vaccines.[1] In addition, Moderna does not anticipate approval of its combination mRNA vaccine mRNA-1083 against influenza and COVID-19 before 2026 due to FDA requests for additional data.[2]