PaxVax, a specialty vaccine company with a commercial focus on travel and biodefense, has entered an R&D collaboration with the University of California, San Diego to develop a combination vaccine to prevent genital herpes simplex virus (HSV) infections.

PaxVax will license intellectual property and work with Deborah Spector, Ph.D., professor in the UC San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences and the university’s Department of Cellular and Molecular Medicine, to select the optimal vaccine combination and take this vaccine candidate into clinical trials. Financial terms were not disclosed.

HSV is one of the most common sexually transmitted diseases in the U.S. and throughout the world, with approximately 750,000 new infections annually in the U.S. alone. Approximately 20% of the U.S. population is infected with HSV. Prescription medicines are available to inhibit virus replication, lessen symptoms and decrease transmission to others, but a treatment does not exist to block the initial infection or onset of HSV. It has been shown that people who are infected with HSV are more susceptible to HIV infection, and thus an effective vaccine for HSV also could reduce HIV transmission rates.

“Spector and her laboratory at UC San Diego have carried out basic and vaccine-related research with HSV and cytomegalovirus for many years, and have developed impressive vaccine strategies, which in animal models show encouraging safety and efficacy,” said Jonathan Smith, executive vice president and chief scientific officer at PaxVax. “We believe that there are synergies between Spector’s approach and technologies developed at PaxVax, such as our oral, adenovirus-based vaccines that could lead to an effective vaccine for HSV. PaxVax also has the necessary manufacturing, regulatory and clinical capabilities and expertise that would allow us to manufacture such an HSV vaccine and test it in a clinical setting.”

PaxVax’s proprietary vector-based technology platform, which would be leveraged to develop the HSV vaccine, has helped the company develop several vaccine candidates that have reached clinical trials, including candidates for pandemic influenza, HIV and anthrax. The oral adenovirus-vectored vaccine candidate, as part of a prime-boost regimen, has the potential to generate more robust antibody responses than traditional vaccine methodologies. PaxVax intends to pursue a similar prime-boost approach using the PaxVax adenovirus technology in conjunction with booster antigens developed by Spector.