NEW YORK – Helocyte, a subsidiary of Fortress Biotech, has gained the exclusive patent rights to use City of Hope's Triplex cytomegalovirus vaccine with a CMV-specific, anti-human immunodeficiency virus CAR T-cell therapy for treating HIV patients.
John Zaia, City of Hope's chair for gene therapy, said the inspiration for combining a vaccine with CAR T-cell therapy came when experts at the cancer center helped a patient achieve remission for both HIV and leukemia. Additionally, a preclinical study published last year suggested that pairing a CMV vaccine with a CMV/HIV CAR T-cell therapy engineered to target gp120, a protein expressed in all HIV viruses and that can carry alterations that allow the virus to evade natural immunity, may yield durable efficacy.
"We are hoping to evaluate a CAR T therapy for HIV in a Phase I clinical trial so that one day more people with HIV might be able to achieve long-term HIV remission," Zaia said in a statement. The first generation of the CAR T-cell therapy will be autologous, according to a Fortress Biotech spokesperson.
The current standard of care for HIV is anti-retroviral therapy, which patients must take for their entire lives to control HIV replications and prevent AIDS, but it isn't curative, and patients can develop resistance. Meanwhile, efforts to develop HIV-specific CAR T-cell therapies haven't been very successful. Experts believe this is because anti-retroviral therapy is effective in reducing HIV viral load to where it cannot activate CAR T cells.
Triplex, developed by City of Hope and licensed to Helocyte in 2015, is designed to stimulate CMV/HIV-CAR T cells so they proliferate in patients. The vaccine is currently undergoing multiple clinical trials for CMV control in pediatric recipients of hematopoietic cell transplants, in adults co-infected with HIV and CMV, and in combination with a CMV/CD19 CAR T-cell therapy in non-Hodgkin lymphoma and others.
The cancer center recently also received an $11.3 million grant from the California Institute for Regenerative Medicine for a Phase I clinical trial that will enroll up to 12 healthy individuals living with HIV-1 who are on stable anti-retroviral therapy and have maintained viral suppression for at least 48 weeks. In addition to dose-escalation and -expansion cohorts, this study will also test whether the vaccine can drive continued proliferation of the CAR. Researchers will enroll patients initially at the University of California, San Diego and City of Hope.