Fred Hutch Scientists Develop First Human Monoclonal Antibodies to Block Epstein-Barr Virus Infection

Fred Hutch Cancer Center (search)Search term scientists have achieved a crucial breakthrough in developing the first genetically human monoclonal antibodies (search)Search drug capable of blocking Epstein-Barr virus (search)Search disease (EBV (search)Search disease) infection, addressing a major challenge in treating a pathogen that infects an estimated 95% of the global population. The research, published in Cell Reports Medicine, demonstrates successful prevention of EBV infection in humanized mouse models and represents a significant step toward protecting high-risk patients from virus-related complications.

Novel Approach Overcomes Long-Standing Challenge

The development of effective antibodies against EBV (search)Search disease has proven particularly challenging due to the virus's unique ability to bind to nearly every B cell in the human immune system. "Finding human antibodies that block Epstein Barr virus from infecting our immune cells has been particularly challenging because, unlike other viruses, EBV finds a way to bind to nearly every one of our B cells (search)Search target," explained Andrew McGuire, PhD, a biochemist and cellular biologist in the Vaccine and Infectious Disease Division at Fred Hutch.

To overcome this obstacle, the research team employed an innovative mouse model carrying human antibody genes, avoiding the common problem of anti-drug responses that occur when patients are treated with antibodies raised in other animals. The researchers targeted two critical viral antigens: gp350 (search)Search target, which helps EBV (search)Search disease bind to cell receptors, and gp42 (search)Search target, which allows the virus to enter and infect human cells through fusion.

Breakthrough Results in Antibody Development

The innovative approach yielded promising results, producing two monoclonal antibodies (search)Search drug against gp350 (search)Search target and eight against gp42 (search)Search target. Through rigorous testing, the team discovered that one monoclonal antibody against gp42 successfully prevented EBV (search)Search disease infection entirely, while another antibody against gp350 provided partial protection.

"Not only did we identify important antibodies against Epstein Barr virus, but we also validated an innovative new approach for discovering protective antibodies against other pathogens," noted Crystal Chhan, a pathobiology PhD student in the McGuire Lab. The research also identified sites of vulnerability that could prove valuable for future vaccine development efforts.

Addressing Critical Unmet Medical Need

The breakthrough holds particular significance for transplant patients, who face elevated risks from EBV (search)Search disease-related complications. More than 128,000 people in the U.S. undergo solid organ and bone marrow transplants annually, yet no specific therapies exist to prevent EBV infection or reactivation in patients requiring immunosuppression for transplant procedures.

Post-transplant lymphoproliferative disorders (search)Search disease (PTLD (search)Search disease) represent one of the most serious EBV (search)Search disease-related complications, manifesting as aggressive and sometimes life-threatening lymphomas that develop after immune suppression. "Post-transplant lymphoproliferative disorders (PTLD), most of which are EBV-associated lymphomas, are a frequent cause of morbidity and mortality after organ transplantation," noted Rachel Bender Ignacio, MD, MPH, an associate professor and infectious disease physician at Fred Hutch and University of Washington School of Medicine (search)Search term.

Clinical Implications and Future Development

Transplant recipients face EBV (search)Search disease infection through multiple pathways: donors previously exposed to EBV may pass latent virus through donor cells, or immunosuppression may cause existing latent virus to replicate unchecked in patients with prior EBV exposure. Children undergoing transplant immunosuppression could particularly benefit from specific EBV therapy, as a higher proportion have not yet been exposed to the virus.

"Preventing EBV (search)Search disease viremia has strong potential to reduce the incidence of PTLD (search)Search disease and limit the need to reduce immunosuppression, thereby helping preserve graft function while improving overall patient outcomes," Dr. Bender Ignacio explained. "Effective prevention of EBV viremia remains a significant unmet need in transplant medicine."

Path to Clinical Translation

The research team envisions developing a therapeutic approach involving monoclonal antibody infusions to prevent PTLD (search)Search disease by blocking EBV (search)Search disease infection and activation in high-risk patient populations. Fred Hutch has filed for intellectual property rights covering the monoclonal antibodies (search)Search drug identified in the study, and McGuire and Chhan are collaborating with scientific partners and an industry collaborator to advance potential therapy development for immunocompromised patients.

The planned development pathway includes initial safety testing in healthy adult volunteers, followed by clinical trials in relevant patient populations if safety profiles prove acceptable. "There's momentum to advance our discovery to a therapy that would make a huge difference for patients undergoing transplant," said McGuire. "After many years of searching for a viable way to protect against Epstein Barr virus, this is a significant stride for the scientific community and the people at the highest risk of complications from this virus."