Preclinical Evaluation of a Novel Immunomodulatory Vaccine for Preventing and Treating HSV Infections

PROJECT SUMMARY: Herpes Simplex Virus (HSV) infections are common, infecting more than half of the world’s population. While most cases of genital herpes are caused by HSV type 2 (HSV-2), it is estimated that more than 150 million people aged 15-49 have genital HSV type 1 (HSV-1) infections. Although several vaccines have been evaluated for preventing/treating HSV infections, none have received FDA approval. Through an exclusive license with Louisiana State University, Rational Vaccines is developing a novel immunomodulatory vaccine engineered not to enter neuronal axons, rendering it incapable of establishing latency within the host. This vaccine was shown to be safe and effective at protecting female mice and guinea pigs from lethal intravaginal challenges with virulent HSV-1 and HSV-2. Further, this vaccine prevented HSV from establishing latency in vaccinated animals, and it induced prolonged immune responses in rhesus macaques. Moreover, the vaccine also exhibited therapeutic potential in guinea pigs latently infected with HSV-2. During the funding period of this Fast-Track proposal, Rational Vaccines will complete the studies required to submit an Investigational New Drug (IND) application to the FDA. In Phase I, process parameters will be developed, pilot batches of the RVx1001 will be manufactured, and product specifications will be drafted. This material will be used to validate the vaccine’s efficacy using the guinea pig model. Phase II will include IND-enabling GLP toxicology studies and scale-up production of the vaccine under current Good Manufacturing Practices (cGMP) to generate clinical trial material. The successful completion of the proposed work will extend to first-in-human clinical studies (beyond the scope of this proposal). Funding the development of this vaccine will play a key role in curbing the spread of HSV-associated conditions.