GlaxoSmithKline PLC (LSE:GSK) said the Coronavirus (COVID-19) vaccine it is developing with French group Sanofi proved effective as a booster shot in a major independent trial.
The jab boosted COVID-neutralising antibodies by a factor of 9 to 43 whatever primary vaccines ((AstraZeneca, Johnson & Johnson (NYSE:JNJ), Moderna, Pfizer/BioNTech) had been received and for all age groups with good safety and tolerability.
Glaxo said though the Omicron variant was not circulating during the trial, but using sera from booster trial participants, testing is underway to establish the ability of the vaccine candidate to cross-neutralize against the new variant.
The phase III trial is ongoing across sites in multiple countries, including the US, France, and the UK with booster data scheduled to be filed with regulatory authorities following the results in the first quarter of next year.
The pharma giants added the work is the most comprehensive booster trial to date across the different technologies used for primary vaccination.
Thomas Triomphe, Sanofi executive vice president, said: "These preliminary data show we have a strong booster candidate, whatever primary vaccine you have received."
Roger Connor, GSK Vaccines’ president, 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."