Tablet Flu Vaccine Looks Promising in Early Trials
Positive safety and immunogenicity data reported (June 19)
Positive safety and immunogenicity data have been reported from phase I clinical studies of an oral-tablet H1N1 seasonal influenza vaccine candidate.
In a placebo-controlled, double-blind, randomized dose-escalation study, the oral vaccine generated serum anti-hemagglutinin (anti-HA) antibody responses and influenza HA-specific T-cell responses in 75% to 80% of the subjects. Neutralizing antibody levels, as determined by microneutralization (MN) assay, were increased in 65% of the subjects, with 35% fully seroconverting (greater or equal to a fourfold increase of MN titers).
In a second open-label study, 25% of the subjects achieved protective HA inhibition (HAI) antibody titers of 1:40 or higher.
The oral H1N1 flu vaccine candidate also demonstrated a positive safety profile, with no vaccine-related significant adverse events. Moreover, there were no tolerability or reactogenicity issues.
According to the vaccine’s developer (Vaxart), the tablets are produced using industry-standard cell-culture and solid-dose manufacturing processes, which allow distribution to the public faster than egg-based influenza vaccine manufacturing technologies.
A phase I clinical study of an H5N1 avian influenza vaccine candidate, also developed by Vaxart, was recently published in Vaccine. In this placebo-controlled, double-blind, randomized, dose-escalation study, subjects received vaccine via enteric-coated capsules.
As in the H1N1 seasonal influenza vaccine studies, the H5N1 avian flu vaccine had a positive safety and tolerability profile, and anti-HA–specific B-cell and T-cell responses were observed in 60% to 80% of the subjects.
A dose-ranging study of the oral H1N1 vaccine has been initiated.
Source: Vaxart; June 19, 2013.