The second dose: The Hindu Editorial on COVID-19 vaccine clearance in India
The HinduWith the U.K. regulator granting an emergency-use authorisation for AstraZeneca’s COVID-19 vaccine on December 30, three vaccines have now been greenlighted for use even before a full approval is granted. While published results show only 62% efficacy when two full-strength doses are administered four weeks apart, the U.K regulator has relied on unpublished data showing efficacy increasing to 73%, 22 days after the first dose when the second jab was delayed. With the virus running amok, the U.K. has revised its policy to delay the second dose of the Pfizer vaccine too despite no trial data to support this; the second Pfizer jab is originally scheduled three weeks after the first. If the pandemic forced scientists, companies and regulators to quickly make available safe and efficacious COVID-19 vaccines, delaying the second dose to maximise the benefits is altogether a new strategy. Since delaying the second dose appears to be increasing the efficacy, and as the U.K. has approved a delayed second dosage, India should carry out large trials to test this.