While many researchers left the DNA vaccine field, Fuller remained, expanding into RNA vaccines as well. After COVID-19, several researchers jumped into studying mRNA’s potential for vaccines and therapeutics. It looked like mRNA had finally broken nucleic acid vaccines into the mainstream.

However, in August 2025, the US Department of Health and Human Services (HHS) canceled $500 million in funding related to mRNA vaccine research under the Biomedical Advanced Research and Development Authority (BARDA). Some contracts, like a late-stage investigation on an influenza vaccine from the biotechnology company Arcturus Therapeutics, were allowed to continue. Others, like mRNA vaccine studies exploring a Marburg vaccine from Moderna, were canceled. Nonetheless, the action sent a shockwave through the mRNA vaccine research community. Later, in February 2026, the FDA initially declined to review an application for an mRNA-based influenza vaccine, disagreeing with the use of control groups in the study. The agency reversed its decision two weeks later.

In response to these events, some researchers are concerned about the future of mRNA technology research and how the US’s disinvestment in it will impact public health. Others, including Fuller, believe that the promise of mRNA vaccines and therapeutics won’t come to a grinding halt anytime soon, but the change in the US’s support for the technology could shift where the next big breakthrough happens.