As per a new study conducted in the UK which suggest that the AstraZeneca Covid-19 vaccine produces an improved immune response with a longer dose gap of up to 45 weeks, and a third shot is able to boost antibody levels even further.
The yet-to-be peer-reviewed study shows that antibody levels remain elevated for at least one year following a single dose of the Oxford-AstraZeneca vaccine, known as Covishield in India where the gap between its two doses has been set at 12-16 weeks. The authors of the study noted that an extended interval of up to 45 weeks, or about 11 months, between the first and second dose of the AstraZeneca vaccine resulted in up to an 18-fold increase in antibody response measured 28 days after the second dose.
The research, posted on the preprint server of The Lancet on Monday, included volunteers aged 18 to 55 years who were enrolled in the trials and had already received either a single dose or two doses of AstraZeneca vaccine. The researchers from the University of Oxford in the UK assessed immune response after a single dose, immunity after an extended interval between the first and second dose, and the response to a third dose as a late booster.