GSK Releases Results From Second Clinical Trial Of H1N1 Vaccine

GlaxoSmithKline (GSK) has reported results from a second clinical trial of its pandemic (H1N1) adjuvanted vaccine, which demonstrated that one dose of the vaccine can provide a strong immune response and exceeds criteria as defined by international licensing authorities using the lowest dose of antigen available in pandemic vaccines.

The company has said that the data from GSK’s H1N1 trials demonstrated the vaccine is generally well tolerated. The vaccine in this trial contains 3.75µg of H1N1 antigen, which is the European Medicines Evaluation Agency (EMEA) approved final formulation.

Reportedly, the trial, which is being taking place in Belgium, involves 130 healthy volunteers aged 18 to 60 years old, and has been designed to evaluate the tolerability and immunogenicity of GSK’s split-virus pandemic (H1N1) adjuvanted vaccine in comparison with an unadjuvanted study formulation.

According to the company, in 100% of the subjects, who received the adjuvanted vaccine, the resulting hemagglutination-inhibition titres exceeded the regulatory threshold of 1:40 seroprotection after the first dose. In the subjects in the unadjuvanted group, 93% reached the same threshold. These results were obtained 3 weeks following vaccination.

The company has added that to date 2,000 people have received GSK’s H1N1 vaccine in clinical trials. Initial results for the first 356 subjects have demonstrated that the H1N1 adjuvanted vaccine has a similar tolerability profile to the previously EMEA approved H5N1 adjuvanted vaccine. The adjuvant system in GSK’s influenza vaccine has already been tested in more than 41,000 people in GSK’s influenza programmes including the H5N1, the H1N1 and the adjuvanted seasonal flu vaccine and candidate vaccines.