A new real-world study has shown that protection offered by Covid-19 vaccines against the disease is waning over time. The ZOE COVID Study app analysed data on positive Covid-19 PCR test results between May and July this year, involving over 1.2 million test results and participants. Findings revealed that protection following two doses of the Pfizer-BioNTech vaccine decreased from 88% at one month to 74% at five to six months. A similar decrease was observed in people who received the AstraZeneca vaccine, with protection falling from 77% to 67% during the same period.
Pfizer and BioNTech have started a rolling submission of a supplemental biologics license application (sBLA) to the US Food and Drug Administration, seeking approval for the booster, or third, dose of their Covid-19 vaccine, Comirnaty, to prevent the disease in people aged 16 years or above. The submission follows the FDA approval of a BLA for a two-dose regimen of the vaccine in this age group. The sBLA comprises data from a Phase III clinical trial in 306 subjects aged 18 to 55 years who received a booster shot of Comirnaty between 4.8 and eight months after the second dose. The companies expect to complete the submission by the end of the week.
Meanwhile, Moderna has completed the rolling submission process for its BLA to the FDA for full approval of its Covid-19 vaccine in people aged 18 years and above.
Johnson & Johnson has reported interim data from two Phase I/IIa clinical trials demonstrating that a booster dose of its single-shot Covid-19 vaccine sharply increased antibodies levels in previously inoculated subjects. The rise in spike-binding antibodies was observed to be nine times higher compared to 28 days after the primary single-dose vaccination. Subjects aged 18 to 55 years and those 65 years and above who were vaccinated with a lower booster dose had substantial rises in binding antibody responses, J&J added.