Sanofi and GSK have announced a single booster dose of their recombinant adjuvanted COVID-19 vaccine candidate delivered consistently strong immune responses in recent clinical trials.
Preliminary results from the VAT0002 trial investigating the safety and immunogenicity of the booster showed neutralising antibodies increased 9- to 43-fold, regardless of the primary vaccine received, for all age groups tested. The booster was well tolerated, with a safety profile similar to currently approved COVID-19 vaccines.
The ongoing global Phase III trial includes regular reviews by an independent Data Safety Monitoring Board (DSMB). During its last review, the DSMB identified no safety concerns and recommended the trial to continue into early 2022 to accrue more data.
Regulatory authorities require Phase III efficacy to be demonstrated in populations who have never been infected by the COVID-19 virus. The Phase III trial recruited most participants in Q3 2021, coinciding with a significant increase in the number of people infected by the virus globally. To acquire the necessary data for the booster vaccine submission, the trial will continue to recruit new participants, with results expected in Q1, 2022.
“These preliminary data show we have a strong booster candidate, whatever primary vaccine you have received.” said Thomas Triomphe, Executive VP, Sanofi Pasteur. “This is consistent with our efforts to provide relevant responses to evolving public health needs. While pursuing a Phase III trial is a challenge in a quickly shifting pandemic environment, we look forward to seeing the results to support submissions of our booster vaccine as quickly as possible.”
Roger Connor, President of GSK Vaccines, added: “As the pandemic threat continues with the current dominant Delta variant and Omicron rapidly gaining ground, booster vaccines will continue to be needed to help protect people over time. The initial booster data are promising, and we await the phase III results to determine the next steps on making protein-based adjuvanted COVID-19 vaccines available."
