Sanofi-GSK vaccine project shows insufficient immune response following its clinical trials, the French drugmaker announced.
Sanofi and Britain’s GlaxoSmithKline said they planned to carry out another study next year, with the objective to develop a more effective vaccine by the end of 2021.
According to Sanofi, the results manifested “an immune response comparable to patients who recovered from COVID-19 in adults aged 18 to 49 years, but a low immune response in older adults likely due to an insufficient concentration of the antigen.”
Phase III studies were expected to begin this month. Sanofi pointed out that it would introduce a phase 2b study in February of next year instead.
“The study will include a proposed comparison with an authorized COVID-19 vaccine,” the company said.
“If data are positive, a global Phase III study could start in Q2 2021. Positive results from this study would lead to regulatory submissions in the second half of 2021, hence delaying the vaccine’s potential availability from mid-2021 to Q4 2021.”
The manufacturers said they had “updated governments and the European Commission where a contractual commitment to purchase the vaccine has been made.”
The Sanofi-GSK vaccine employs the same recombinant protein-based technology as one of Sanofi’s seasonal influenza vaccines. It will come with an adjuvant, a substance that becomes a booster to the vaccine.
In July, the U.K. government has signed an agreement with pharmaceutical giants GSK and Sanofi to secure up to 60 million doses of an experimental coronavirus vaccine.
The new deal signed by the UK government and with GSK and Sanofi for their coronavirus vaccine will add to the existing deal it signed with AstraZeneca for 100 million doses of the Oxford University vaccine.
According to Sanofi, regulatory approval could be achieved by the first half of 2021 if trials were successful. While waiting for approval, both firms are scaling up manufacturing to produce up to one billion doses a year overall.
The vaccine in question has been the topic of an international political debate when Sanofi stepped back from its initial promise to prioritize the US market for its vaccine.
In May, Sanofi chief executive officer (CEO) Paul Hudson said the US government had “the right to the largest pre-order because it’s invested in taking the risk”.
However, Hudson changed his stand after then French Prime Minister Edouard Philippe responded by saying access for all was “non-negotiable”. The latest announcement from GSK and Sanofi emphasized that they were “committed to making the vaccine available globally”.
Thomas Triomphe, executive vice-president and global head of Sanofi Pasteur, said: “With our partner GSK, we are pleased to co-operate with the UK government as well as several other countries and global organizations as part of our ongoing efforts to develop a safe and effective vaccine and make it available as quickly as possible.”
GSK Vaccines president Roger Connor added: “We thank the UK government for confirmation of purchasing intent, which supports the significant investment we are already making as a company to scale up development and production of this vaccine.”
