Ayyyeee… What’s Goodie Everyone. So I got some tea and it involves information on the coronavirus vaccine by another company.
AstraZeneca became the third pharmaceutical company to announce positive results from late stage trials of a coronavirus vaccine, saying that its candidate, developed by Oxford University, is up to 90 percent effective.
Scientists and politicians hailed the third straight week of scientific news as a sign that, even as coronavirus cases surge to devastating levels in many countries, an end to the pandemic is in sight.
Pfizer and its German partner BioNTech and Moderna have each reported vaccines that were 95 percent effective in clinical trials. The AstraZeneca trial was 70 percent effective overall, with up to 90 percent efficacy in a smaller group that got a lower dosage. Different trial designs make direct comparison complicated, but with somewhat lower protection, the AstraZeneca vaccine may be a more realistic option for much of the world, as it is likely to be less expensive and does not need to be stored at subzero temperatures.
The Oxford-AstraZeneca team said in a video conference with journalists that its candidate offered 90 percent protection against the coronavirus when a subject received half a dose, followed with a full dose one month later. Efficacy was lower 62 percent when subjects received two full doses a month apart.
The AstraZeneca results have yet to be peer reviewed or even published, and outside scientists said that much depended on seeing those in detail. Many questions remain, including why the lower dose regimen was more effective. It is also unclear whether the vaccine can reduce transmission of the coronavirus by people who have no symptoms, which would have repercussions for how soon people could stop wearing masks. No one yet knows how long immunity from the vaccine will last.
Sarah Gilbert, who is a lead Oxford researcher, cautioned that the dose and a half regimen would have to be studied more closely to be fully understood. But she said that the first half dose might be priming a person’s immune system just enough, and that the booster would then encourage the body to produce a robust defense against infection.
The company said it will present the results to Britain’s health care products regulators immediately and begin seeking emergency authorization in the United States. It is still only midway through its U.S. clinical trial, though, and now wants to adjust the format to further assess the half dose shot plus booster.
Participants who received the vaccine developed no severe cases of the coronavirus or required hospitalization, AstraZeneca said Monday. The drugmaker also said that no “serious safety events” were reported in connection with the vaccine, which was typically “well tolerated” by participants regardless of their dosing levels or ages.
The vaccine uses a harmless cold virus that typically infects chimpanzees to deliver to the body’s cells the genetic code of the spike protein that dots the outside of the coronavirus. That teaches the body’s immune system to block the real virus.
The reason the regimen with an initial half dose worked better remains unclear, some people close to the research have said that it could be related to the fact that the body’s immune system can develop a defense mechanism to block the harmless virus that’s used to deliver the spike protein’s code. Giving a smaller initial dose may lessen those defenses, and make the vaccine more effective.
Other vaccines in late stage development use a similar technology, harnessing a harmless virus to deliver a payload that will teach the immune system how to fight off the real thing including a Johnson & Johnson vaccine, a Russian vaccine being developed by the Gamaleya Research Institute and a vaccine made by CanSino Biologics in China.
The Pfizer and Moderna vaccines both use messenger RNA, a new vaccine platform never approved in a medical product for people.