A new vaccine to fight fungal infections has passed clinical trials

The University of Georgia has developed a new vaccine that has the potential to become the first vaccine to receive clinical approval for the protection against invasive fungal infections.

Invasive fungal infections have recently become a significant concern due to the increasing resistance to antifungal drugs. The new vaccine, if clinically approved, could provide a much-needed solution to this growing problem and help prevent the spread of these infections.

1.5 million deaths worldwide every year

Fungal infections are a major public health problem that results in a significant number of deaths each year. According to estimates, these infections cause over 1.5 million deaths worldwide every year and result in billions of dollars in economic costs. The impact of these infections is particularly severe in hospitalized patients, where they increase the duration of stay in a hospital and double the risk of death. 

A previous study by the University of Georgia (UGA) found that fungal infections also double the cost of hospitalization. Despite the significant impact of fungal infections, there are currently no effective vaccines available to protect vulnerable patients from these infections. This highlights the urgent need for a safe and effective vaccine to address this growing public health problem.

"There is a pressing need for both prevention and treatment solutions for fungal infections, especially among individuals with weakened immune systems," said Karen Norris, the new study's lead researcher and a professor at the College of Veterinary Medicine. "The number of patients at risk for invasive fungal infections has risen significantly in recent years."

How the new vaccine works

The newly developed vaccine targets the three most prevalent fungal pathogens responsible for most fatal fungal infections. In the study, the vaccine's efficacy was evaluated in four preclinical animal models, including non-human primates.

The researchers used various immune-compromised models, mirroring drug regimens that are common among transplant recipients, people with HIV, and cancer patients – groups that are among the most vulnerable. The vaccine was found to effectively trigger the production of protective antibodies in all models.

"With its ability to address three different pathogens, this vaccine has the potential to revolutionize the way we approach invasive fungal infections," Norris, who is also a faculty member of the university's Center for Vaccines and Immunology, stated. "Plans are underway to proceed with a Phase I safety trial for human use."

Justin Beardsley, a researcher in infectious diseases from the University of Sydney, collaborated with the WHO to create the Fungal Priority Pathogen list in 2022. According to Beardsley, fungi are the "neglected" infectious microorganisms that cause serious illnesses, yet their extent remains largely unknown. He stressed the importance of researching current and emerging fungal pathogens, which have long been overlooked.

The study, published in PNAS Nexus, was a collaboration between authors from the College of Veterinary Medicine and the Franklin College of Arts and Sciences. The research was funded and supported by the Centers for Disease Control and Prevention, the National Institutes of Health, the Georgia Research Alliance, and the University of Georgia Research Foundation.

Study abstract:

Invasive fungal infections cause over 1.5 million deaths worldwide. Despite increases in fungal infections as well as the numbers of individuals at risk, there are no clinically approved fungal vaccines. We produced a “pan-fungal” peptide, NXT-2, based on a previously identified vaccine candidate and homologous sequences from Pneumocystis, Aspergillus, Candida, and Cryptococcus. We evaluated the immunogenicity and protective capacity of NXT-2 in murine and nonhuman primate models of invasive aspergillosis, systemic candidiasis, and pneumocystosis. NXT-2 was highly immunogenic and immunized animals had decreased mortality and morbidity compared to nonvaccinated animals following induction of immunosuppression and challenge with Aspergillus, Candida, or Pneumocystis. Data in multiple animal models support the concept that immunization with a pan-fungal vaccine prior to immunosuppression induces broad, cross-protective antifungal immunity in at-risk individuals.