Sanofi and GSK Launch New Covid-19 Vaccine Study

Sanofi and GSK announced plans to submit research data that forms the basis of their joint Covid-19 vaccine license applications. The data to be used in the application includes results from both an immunity-boosting booster vaccine and Phase 3 efficacy trials. The Sanofi-GSK vaccine with stable adjuvant protein base, which can be stored at refrigerator temperature and thus has a distinctive feature for public health, was found to trigger strong immune responses and maintain an appropriate safety profile across multiple settings.

Antibodies increased 84 to 153 fold

When the Sanofi-GSK immune-boosting booster dose was administered to participants who had received an initial dose of an mRNA or adenovirus vaccine, it provided a significant increase in neutralizing antibodies ranging from 18 to 30 fold across different vaccine platforms and age groups. When the Sanofi-GSK vaccine was used as a two-dose primary series followed by a booster dose, neutralizing antibodies increased 84 to 153 fold compared to pre-booster levels. Thomas Triomphe, Senior Vice President of Sanofi Vaccines Global, commented on the matter saying "We are very pleased with these data from our robust scientific studies confirming the benefits of our COVID-19 vaccine. The Sanofi-GSK vaccine demonstrates universal competency to strengthen all platforms and people of all ages. Additionally, we observed strong efficacy of the vaccine as a primary series in today's challenging pandemic environment. During this period, no other global Phase 3 efficacy study was conducted with so many concerning variants including Omicron, and this efficacy data is comparable with recent clinical data from approved vaccines." he said. GSK Vaccines President Roger Connor stated "The evolving epidemiology of COVID-19 demonstrates the need for different vaccines. Our protein-based adjuvanted vaccine candidate uses an established approach widely applied to prevent infection with other viruses, including pandemic influenza. We are confident this vaccine could play an important role as we continue to address this pandemic and prepare for the post-pandemic period."

Neutralizing antibodies at strong levels

When used as a two-dose primary series vaccine, the Sanofi-GSK vaccine provided neutralizing antibodies at strong levels with GMT (Geometric Mean Titers) reaching 3,711 units. For comparison, blood serum samples from volunteers in the same age range who received two doses of an already approved and highly effective mRNA vaccine showed a GMT level of 1,653 units when measured simultaneously in the same laboratory. Data from the VAT08 efficacy trial showed that two doses of the Sanofi-GSK vaccine provided 57.9 percent efficacy against any symptomatic COVID-19 disease in the seronegative population (people without antibodies in the blood). The Sanofi-GSK vaccine provided 100 percent protection against severe disease and hospitalization (0 versus 10 cases after dose 1, 0 to 4 cases after dose 2) and 75 percent efficacy against moderate to severe disease (3 to 11 cases). While sequencing studies in seronegative populations are ongoing, early data showed 77 percent efficacy against any symptomatic COVID-19 disease associated with Delta variant, consistent with expected vaccine efficacy. In both studies, the Sanofi-GSK vaccine was well tolerated in both young and elderly adults without safety concerns. The two companies continue discussions with drug licensing authorities including the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). They plan to submit all data provided regarding the vaccine candidates in their applications to support the licensing approval processes.