Fortress Biotech Begins Multi-Center Phase 2 Study of Triplex for CMV Control in Liver Transplant Patients

Fortress Biotech, Inc., a pioneering biopharmaceutical company, and its majority-owned subsidiary, Helocyte, Inc., have announced the dosing of the first patient in a multi-center, placebo-controlled, randomized Phase 2 study of Triplex, a vaccine designed to manage cytomegalovirus (CMV) in liver transplant recipients. The trial is financed by a substantial grant from the National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIH/NIAID), awarded to the University of Washington Seattle. The grant has already contributed $9.0 million, with an expected additional $12 million over the next four years for the Phase 2 clinical trial. This study will be conducted across up to 20 prominent transplant centers in the United States.

Triplex, a vaccine originally developed by City of Hope—a renowned cancer treatment and research institution—and exclusively licensed to Helocyte, is being evaluated in this trial to determine its safety and efficacy in improving outcomes for liver transplant recipients. Ajit Limaye, M.D., a Professor of Medicine and Director of the Solid Organ Transplant Infectious Disease Program at the University of Washington, is the Principal Investigator of the trial titled “CMV vaccine in Orthotopic Liver Transplant” (COLT). Dr. Limaye emphasized the importance of this milestone, highlighting the significant need for new therapies to mitigate the frequency and severity of CMV events in organ transplant patients, where CMV poses life-threatening complications that affect patient survival.

The COLT trial, a multi-center, randomized, placebo-controlled, double-blinded study, aims to enroll up to 416 CMV seronegative liver transplant candidates. The primary goal is to assess the impact of pre-transplant Triplex vaccination on the duration of CMV antiviral therapy within the first 100 days post-transplant in recipients whose liver donor is CMV seropositive. Secondary endpoints include the development of CMV disease within six months post-transplant and the time to onset of such disease.

Lindsay A. Rosenwald, M.D., Chairman, President, and CEO of Fortress, expressed satisfaction with the progression of Triplex in this Phase 2 trial. He noted that if successful, the trial could demonstrate Triplex’s potential to significantly enhance outcomes, reduce morbidity, and lower mortality rates for liver transplant recipients. Triplex is also being studied in various other clinical trials for CMV prevention and treatment in different transplant scenarios and in HIV patients. Rosenwald anticipates providing more updates as these trials advance.

Triplex is a universal recombinant Modified Vaccinia Ankara viral vector vaccine engineered to induce a robust and durable virus-specific T cell response to three CMV-associated proteins: UL83 (pp65), UL123 (IE1), and UL122 (IE2). Previous Phase 1 and Phase 2 studies have shown Triplex to be safe, well-tolerated, and highly immunogenic. Current clinical trials include a Phase 2 study for CMV control in liver transplant recipients, a Phase 1/2 trial for CMV control in pediatric hematopoietic cell transplantation (HCT) recipients, and several other Phase 2 trials for both HIV and CMV.

Helocyte, a clinical-stage company, is focused on developing novel immunotherapies for cancer and infectious diseases, including CMV and human immunodeficiency virus (HIV). The Centers for Disease Control estimate that a significant portion of Americans are living with CMV by the age of 40. CMV is generally asymptomatic in healthy individuals but can cause severe and life-threatening diseases in immunocompromised patients, such as those undergoing allogeneic stem cell and solid organ transplantation. Current antiviral therapies, while reducing CMV disease-related mortality, have drawbacks such as increased toxicity and delayed immune reconstitution. Helocyte’s vaccines aim to mitigate these issues by educating the body’s immune system to combat CMV effectively.