Nearly all instances of cervical cancer are caused by high-risk human papillomavirus (HPV) strains. Cervarix® and Gardasil® 9 are the most recent preventive vaccinations that protect against the vast majority of HPVs linked to cancer. Despite the fact that these vaccinations are extremely effective, the adoption of HPV vaccines has been sluggish, particularly in low- and middle-income countries. The expense of the HPV vaccinations, as well as the need for continual refrigeration, are major impediments to their broad distribution. Researchers created a thermostable Gardasil® 9 vaccination using spray drying and stabilizing excipients. They tested the vaccine’s immunogenicity and protective effectiveness in mice immediately after spray drying and three months later at 4°C, 25°C, and 40°C. For ELISA, the immunogenicity tests were conducted using Gardasil® 9 as a whole antigen rather than specific HPV types. Following storage at temperatures up to 40°C, the spray-dried vaccine provided protection against HPV at the dose tested. In addition to the spray-dried vaccine, the research found that the Gardasil® 9 vaccination, as it is presently sold, may be kept and transported at high temperatures for up to 3 months without losing efficacy, particularly against HPV16.

This research is significant because a thermostable vaccine would reduce vaccination costs related to cold-chain maintenance and may enhance vaccine access and coverage, particularly in remote areas of the world.