NEW ORLEANS, LA – The U.S. Food and Drug Administration (FDA) has approved XOFLUZA® (baloxavir marboxil) for the treatment of acute, uncomplicated influenza in patients 12 years and older who have been symptomatic for no more than 48 hours. This first-in-class antiviral, developed by Shionogi & Co., Ltd., is administered as a single oral dose and introduces a novel mechanism of action that inhibits viral replication at the source. Tyler Hastings, Managing Partner at DelRicht Research, emphasized the significance of this milestone, noting the local team’s contribution to a therapy that improves both patient outcomes and treatment adherence.

Dr. Patrick Dennis, Principal Investigator at Touro Medical Center in New Orleans, LA, contributed to the pivotal clinical trial supporting this approval through his work with DelRicht Research. Dr. Dennis has led numerous trials with DelRicht since 2016 across multiple therapeutic areas, including infectious disease, pediatrics, and respiratory conditions.

Tyler Hastings Reflects on Xofluza as a First-in-Class Flu Treatment

Unlike traditional antivirals that require multiple doses over several days, XOFLUZA works through a cap-dependent endonuclease inhibition mechanism that targets viral replication early in the infection cycle. In clinical trials, a single dose significantly reduced the duration of flu symptoms compared to placebo and performed comparably to oseltamivir (Tamiflu®), with fewer reported adverse events.

The approval follows a Priority Review by the FDA, reflecting the urgent need for new influenza treatments with simpler dosing and improved adherence, especially in high-burden seasons. The Phase III CAPSTONE-1 trial enrolled over 1,400 otherwise healthy patients and demonstrated a median symptom resolution time of 53.7 hours with XOFLUZA, compared to 80.2 hours for placebo.

“This approval represents a meaningful leap forward in the treatment of seasonal influenza,” said Tyler Hastings, Managing Partner at DelRicht Research. “A single-dose therapy that reduces symptoms faster and supports adherence has real-world impact, and we’re proud that Dr. Dennis and our New Orleans site helped support the trial that led to this milestone.”

“This approval represents a meaningful leap forward in the treatment of seasonal influenza. A single-dose therapy that reduces symptoms faster and supports adherence has real-world impact, and we’re proud that Dr. Dennis and our New Orleans site helped support the trial that led to this milestone.”

— Tyler Hastings, Managing Partner at DelRicht Research

Local Research Supporting Global Impact

The approval of XOFLUZA reinforces the importance of innovative antiviral development and the role local investigators play in bringing new treatments to market. Dr. Dennis’s work on the XOFLUZA trial exemplifies DelRicht Research’s commitment to advancing care through high-quality site performance and diverse patient engagement.

“In a typical flu season, timely treatment can mean the difference between quick recovery and prolonged illness,” said Dr. Patrick Dennis, Principal Investigator. “XOFLUZA’s single-dose approach offers a much-needed alternative for patients and providers looking for fast, effective treatment options.”

“In a typical flu season, timely treatment can mean the difference between quick recovery and prolonged illness. XOFLUZA’s single-dose approach offers a much-needed alternative for patients and providers looking for fast, effective treatment options.”

— Dr. Patrick Dennis, Principal Investigator at DelRicht Research

XOFLUZA is also being studied in broader patient populations, including those at high risk for complications, pediatric groups, and hospitalized individuals. These ongoing trials continue to expand the treatment’s relevance and potential global health impact.

Advancing Antiviral Options When They’re Needed Most

As influenza continues to cause widespread illness, hospitalization, and death each year, XOFLUZA arrives as a promising new tool in the fight against seasonal and pandemic flu. With support from dedicated investigators like Dr. Dennis and the broader DelRicht Research network, innovative therapies like XOFLUZA can reach the patients who need them faster and more effectively than ever before.

Read the full press release from Shionigi.