It may seem surprising to stop a multimillion-dollar, 30,000-person trial because one person fell ill, but 'it's not at all unprecedented,' said Dr. Francis Collins, director of the National Institutes of Health. Here's what we know.
is the first major setback in pursuit of a vaccine against a disease that has now killed 190,000 in the U.S. and nearly 900,000 worldwide. One volunteer in a trial in the United Kingdom apparently developed a serious neurological problem after receiving the vaccine, though not much has been made publicly available about what happened.
AstraZeneca, which is running several large trials around the world, including one in the U.S., put a temporary hold on all of them pending an investigation. It may seem surprising to stop a multimillion-dollar, 30,000-person trial because one person fell ill, but"it's not at all unprecedented," said Dr. Francis Collins, director of the National Institutes of Health, speaking Wednesday morning to a Senate committee. Overall, only about 25% of vaccines that enter human testing end up receiving approval and being marketed to the public,That's why the federal government has invested in six different candidate vaccines, Collins said,"because of the expectation that they won’t all work – though it would be lovely if they did." The government has pledged more than $10 billion to six companies now developing candidate vaccines, with the possibility of adding one or two more. The money is intended to cover development costs for most of the vaccines and production and distribution of 100 million doses of each by early next year. If any vaccine fails to meet standards of safety and effectiveness, those pre-made doses will be thrown out. The governmentwith AstraZeneca in May that calls for the company to make 300 million doses of its vaccine It's not clear whether AstraZeneca has already begun making doses of its vaccine, currently called AZD1222. Research trials are routinely stopped if the drug or vaccine being tested may have caused harm. During the stoppage, an independent Data Safety Monitoring Board, which oversees the trial, will review what happened and decide whether it is safe for the trial to resume. Anytime there is a trial of 30,000 people – especially in this case, where many of the trial participants are older adults with other health conditions – someone will have an accident or a heart attack, said Barry Bloom, an immunologist at the Harvard T.H. Chan School of Public Health. It will be challenging to determine whether the person's problem was coincident to the trial or caused by it, Bloom and others said. Collins said the hold should be reassuring to people who are concerned about the COVID-19 vaccine process because it shows safety is being taken seriously. "This ought to be reassuring to anyone listening when we say we are going to first focus on safety and make no compromises – here is Exhibit A about how that is happening in practice," Collins said."I’m ready to roll up my sleeve as soon as they say it's safe to take."How common are vaccine trials halted? All of the COVID-19 vaccine trials have proceeded without any problems for months. But it is not unexpected that some trial participants would have health problems. "These are vaccines to prevent COVID-19 infection, not everything else that happens in life," said Dr. Paul Offit, a vaccine development specialist at the Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania. The key question is:"Is it coincidental or causal?" The trials intentionally include large numbers of older adults and those with other health problems to make sure any vaccine that reaches the general public will be safe and effective for groups most at risk from COVID-19. The company did the right thing to stop its trial and investigate whether the vaccine may have caused the problem or simply happened around the same time, Offit said."It's prudent of the company to take a step back," he said."They're doing testing now to try and figure out how to explain this disease."The result will depend on whether the trial is stopped permanently, or just for a little while. If the person's illness is considered a result of the vaccine, the company or the Data Safety Monitoring Board could decide that AstraZeneca's candidate vaccine, AZD1222, isn't safe enough to give to large numbers of people. Based on technology developed by Oxford University, the vaccine uses a chimpanzee virus to deliver a bit of protein normally found on the outside of the SARS-CoV-2 virus that causes COVID-19. Once a person has received the vaccine, their body will be primed to fight off the SARS-CoV-2 virus if exposed. Harvard's Bloom said he doesn't think the chimpanzee virus could be the cause of the trial participant's neurological problem. But he said the coronavirus itself can cause such problems. In the 1970s, a flu vaccine was connected to cases of a rare neurological condition called Guillain-Barré syndrome, although it was never clear whether the vaccine or the flu virus caused the syndrome.
Please follow us on Google to support us United States Latest News, United States Headlines
Similar News:You can also read news stories similar to this one that we have collected from other news sources.
AstraZeneca Pauses Covid-19 Vaccine Trial After Illness in a U.K. SubjectAstraZeneca said it paused clinical trials of an experimental Covid-19 vaccine after a participant in a U.K. study had an unexplained illness.
Read more »
AstraZeneca pauses Covid-19 vaccine trial – latest updatesA look at latest developments in global Covid-19 crisis👇: 💉 AstraZeneca suspends vaccine trial after one illness 🇬🇧 UK plans hiring spree to harness big data in virus recovery 🇧🇷 Brazil eyes vaccine rollout in January For more:
Read more »
AstraZeneca puts leading COVID-19 vaccine trial on hold over safety concernAstraZeneca Plc on Tuesday said it has paused global trials, including large late-stage trials, of its experimental coronavirus vaccine because of an unexplained illness in a study participant.
Read more »
AstraZeneca COVID-19 vaccine tests paused after participant becomes illStudies of AstraZeneca’s COVID-19 vaccine candidate are on hold while the company investigates whether a recipient’s illness is a side effect of the shot.
Read more »
AstraZeneca suspends leading COVID-19 vaccine trials after a participant's illnessAstraZeneca Plc said it has paused global trials, including large late-stage trials, of its experimental coronavirus vaccine due to an unexplained illness in a study participant.
Read more »
AstraZeneca Pauses COVID-19 Vaccine Trial Due To Volunteer's IllnessNPR's Noel King talks to Paul Offit of the Vaccine Education Center at Children's Hospital of Philadelphia, about the coronavirus vaccine trial developed by AstraZeneca and the University of Oxford.
Read more »