The FLUNITY-HD study, a prespecified pooled analysis combined data from two large-scale trials — DANFLU-2 in Denmark and GALFLU in Galicia, Spain — and included more than 466,000 individually randomized older adults across three flu seasons. The study assessed the benefits of high-dose vs. standard-dose (SD) influenza vaccines against hospitalizations in older adults. The international collaboration was made possible through the efforts of investigators Dr. Tor Biering-Sørensen in Denmark and Dr. Federico Martinón-Torres in Spain, along with their dedicated research teams.

“FLUNITY-HD is the largest individually randomized influenza vaccine effectiveness study,” said Loiacono. “Its findings add to the existing body of evidence of the high-dose vaccine’s clinical performance versus the standard-dose vaccine, assessed across nearly a half-million individually randomized older adults.”

The news comes on the heels of a severe flu season last year, which saw the highest hospitalization rates since 2010, and could inform clinical guidelines. 

“These new data are particularly relevant for older adults, who are especially vulnerable to flu and the numerous complications it can cause,” Loiacono said. 

Loiacono anticipates potential future analyses of the FLUNITY-HD data that may focus on older adults with heart disease, chronic kidney disease, and immunocompromised individuals.

“With nearly a half-million individually randomized older adults, this study presents a unique opportunity to explore a lot of important questions and assess the potential benefit of the high-dose vaccine across risk groups,” Loiacono said.

Industry and academic partnerships power research

Loiacono joined UD’s Department of Epidemiology within the last year as an affiliated faculty member after being recruited by collaborator Daniel Harris, assistant professor of epidemiology. 

“Loiacono’s work with Sanofi bridges academic and industry research to answer pressing public health questions,” Harris said. “It’s exciting for our students to see how partnerships like these can lead to discoveries that directly improve patient outcomes.”

In his role, Loiacono expands the department’s expertise and reach, advising and supporting students and exposing them to the pharmaceutical industry. 

“I was in their shoes not too long ago, and I hope to give them a peek under the hood and expose them to a different avenue of research,” Loiacono said. 

Loiacono inspired Peyton Free, a 2025 graduate of UD’s master of public health in epidemiology, during a lecture last semester. 

“Dr. Loiacono opened me up to the world of vaccine development and sparked my interest in vaccinations, specifically vaccine-preventable diseases,” Free said.  

Loiacono also emphasized the importance of partnerships between industry and academia in producing research studies, such as FLUNITY-HD. 

“Nearly everything I’ve done in the industry has only been made possible because of external experts and academics,” Loiacono said. “The vast majority of research our team at Sanofi does is accomplished through academic-led collaborations. We work collaboratively with academic experts, providing resources and our own expertise, but most importantly, we then hand the reins over to the principal investigators and their teams. These collaborative relationships make landmark research like the FLUNITY-HD study possible.”

The views expressed here by Matthew Loiacono are his own and do not necessarily reflect the views of Sanofi.