Hydroxypropyl-β-cyclodextrin (HP-β-CyD) is a substance commonly used as an excipient in pharmaceutical products. Recently, it has been discovered that HP-β-CyD can also function as a vaccine adjuvant, which means it can enhance the immune response to co-administered antigens. In this clinical trial, researchers investigated the safety and effectiveness of a seasonal influenza vaccine that was adjuvanted with HP-β-CyD (FluCyD-vac) in healthy adults compared to a standard seasonal influenza vaccine (Flu-vac).
The study was a single-blinded randomized phase 1 clinical trial, which means that the participants were randomly assigned to receive either FluCyD-vac or Flu-vac, and neither the participants nor the researchers knew which vaccine was being administered. The scientists used two types of flu vaccines: FluCyD-vac and Flu-vac. FluCyD-vac has less flu virus protein (9 μg) but has another substance called HP-β-CyD (20%). Flu-vac has more flu virus protein (15 μg) but does not have HP-β-CyD.
The study had 36 healthy people who participated. Out of these, 24 people got FluCyD-vac and 12 people got Flu-vac. The scientists checked for any expected or unexpected side effects (AEs) and checked how well the vaccines worked by measuring ‘’hemagglutination inhibition (HI) titers". They also checked how the T-cells in blood reacted to the vaccines using flow cytometry.
The study found that FluCyD-vac was safe to use, and the side effects were mostly mild and related to the injection site. No serious side effects were reported in either group. The results showed that FluCyD-vac worked just as well as Flu-vac, even though it had less flu virus protein. The immune response of people who got FluCyD-vac was good enough to meet international standards. The study also found that FluCyD-vac helped boost a type of immune cell called "tumor necrosis factor (TNF)-α-producing CD4+ T cells" when PBMCs(Peripheral blood mononuclear cells) were stimulated with the vaccine.
The study showed that FluCyD-vac is a potentially safe and effective influenza vaccine adjuvant despite containing 40% fewer HA antigens than Flu-vac. The use of HP-β-CyD as a vaccine adjuvant could lead to the development of more effective vaccines with fewer antigens, which could be particularly important for those who have difficulty mounting a strong immune response, such as the elderly or immunocompromised individuals.
If you are interested in getting vaccinated against the flu, it is important to speak with your healthcare provider to determine if the flu vaccine is appropriate for you. The flu vaccine is recommended for everyone over the age of 6 months, but there are some people who should not receive the vaccine, such as those who have severe allergies to any component of the vaccine or who have had a severe reaction to the vaccine in the past.
Overall, the results of this study are encouraging and suggest that HP-β-CyD could be a promising adjuvant for future vaccines. As research continues in this area, we may see the development of even more effective and safe vaccines that can protect us from a range of infectious diseases.