Vaxart Publishes Preclinical Data on Mucosal Vaccine for HPV Cervical Dysplasia

Vaxart, Inc. has recently published preclinical data showcasing the potential of its mucosal vaccine technology to treat HPV-related cervical dysplasia. The findings, detailed in the journal Vaccines, reveal that Vaxart’s HPV vaccine constructs can elicit a strong immune response targeting HPV16 proteins E6 and E7, which are implicated in the transformation of healthy cells into malignant ones. The results suggest that the vaccine can significantly reduce tumor size and enhance survival rates in mice with HPV-related tumors.

Persistent HPV infection is a major cause of cervical dysplasia, which can progress to cervical cancer if not treated. While existing prophylactic HPV vaccines are effective when given before infection, they have not shown therapeutic benefits for existing infections. The data from Vaxart’s research indicate that the company’s mucosal vaccines can activate T cells to attack HPV-expressing cells, resulting in smaller tumors and improved survival in animal models.

Dr. Sean Tucker, Vaxart’s Founder and Chief Scientific Officer, emphasized the significance of these findings. He pointed out that although further research is needed to better understand the immune-stimulating and anti-tumor properties of their HPV vaccine, the initial data suggest that Vaxart's mucosal vaccine platform could offer a non-invasive method to prevent the progression to cervical cancer. Dr. Tucker also noted that the ease of administration and room-temperature stability of these mucosal vaccines could help address disparities in the treatment of HPV-related cancers globally.

In the study, researchers evaluated the therapeutic potential of Vaxart’s platform in mice with HPV-expressing tumors. The animals received various vaccine candidates expressing wildtype and engineered forms of HPV16 E6 and E7 antigens, as well as fragments of these proteins predicted to provoke an immune response. The key outcomes of the study included:

- Specific T cell responses to HPV16 E6 and E7 were generated by all vaccine formulations.
- Significant reductions in tumor size and increased survival were observed in vaccinated mice compared to control groups.
- Concurrent administration of anti-PD-1 with the vaccine further boosted survival rates in both small and large tumor models.
- Vaccination resulted in notable increases in intra-tumoral T cells, particularly those creating a cytotoxic tumor environment, compared with an empty control vaccine.
- Generation of antigen-specific cytotoxic T cells was documented following vaccination.

These results propose that rAd5 vaccines administered to a mucosal surface could have therapeutic potential in treating HPV-induced cervical dysplasia and might stimulate immune responses against other cancer-related proteins. Vaxart continues to investigate its HPV vaccine candidates.

Vaxart, a clinical-stage biotechnology firm, is developing a range of oral recombinant vaccines using its proprietary delivery platform. These vaccines are designed for oral administration via pills that do not require refrigeration, thus minimizing the risk of needle-stick injuries. The company’s current development programs include vaccines for coronavirus, norovirus, influenza, and a therapeutic vaccine for HPV, marking its first foray into immune-oncology. Vaxart has filed comprehensive domestic and international patent applications to protect its innovative technology and methods for oral vaccination using adenovirus and dsRNA agonists.