<p>Pfizer Inc and its German partner BioNTech SE have submitted to US regulators the initial data from an early-stage trial toward seeking authorisation of a booster dose of their Covid-19 vaccine, the drugmakers said on Monday.</p>.<p>They said the third dose showed significantly higher neutralising antibodies against the initial SARS-CoV-2 virus compared to the two doses as well as against the Beta and the highly infectious Delta variants.</p>.<p>Pfizer has said its vaccine's efficacy drops over time, citing a study that showed 84% effectiveness from a peak of 96% four months after a second dose. Some countries including Israel have already gone ahead with plans to give booster doses.</p>.<p>However, the decision by a few rich countries to buy booster shots has drawn the ire of health activists and the World Health Organization, which has called for a moratorium on boosters until at least the end of September.</p>.<p>Pfizer and BioNTech had said that all patients in the trial received the third shot, BNT162b2, eight to nine months after their second dose.</p>.<p>The drugmakers will submit the trial data to the European Medicines Agency and other regulatory authorities in the coming weeks. They said results from a late-stage trial of the third dose are expected shortly.</p>.<p>Last week, US regulators authorised a third dose of Covid-19 vaccines by Pfizer-BioNTech and Moderna Inc for people with compromised immune systems who are likely to have weaker protection from the two-dose regimens.</p>
<p>Pfizer Inc and its German partner BioNTech SE have submitted to US regulators the initial data from an early-stage trial toward seeking authorisation of a booster dose of their Covid-19 vaccine, the drugmakers said on Monday.</p>.<p>They said the third dose showed significantly higher neutralising antibodies against the initial SARS-CoV-2 virus compared to the two doses as well as against the Beta and the highly infectious Delta variants.</p>.<p>Pfizer has said its vaccine's efficacy drops over time, citing a study that showed 84% effectiveness from a peak of 96% four months after a second dose. Some countries including Israel have already gone ahead with plans to give booster doses.</p>.<p>However, the decision by a few rich countries to buy booster shots has drawn the ire of health activists and the World Health Organization, which has called for a moratorium on boosters until at least the end of September.</p>.<p>Pfizer and BioNTech had said that all patients in the trial received the third shot, BNT162b2, eight to nine months after their second dose.</p>.<p>The drugmakers will submit the trial data to the European Medicines Agency and other regulatory authorities in the coming weeks. They said results from a late-stage trial of the third dose are expected shortly.</p>.<p>Last week, US regulators authorised a third dose of Covid-19 vaccines by Pfizer-BioNTech and Moderna Inc for people with compromised immune systems who are likely to have weaker protection from the two-dose regimens.</p>