Oxford / AstraZeneca coronavirus vaccine results released

The first peer-reviewed results were published on Tuesday, describing the clinical trials of a COVID-19 vaccine developed by Oxford University and the drug company AstraZeneca. Preliminary announcement Created in late November aroused confusion and criticism among scientists.

The PaperPublished in the medical journal The Lancet, Oxford conducted vaccine tests in the United Kingdom, Brazil and South Africa. Overall, data from the UK and Brazil indicate that the vaccine was 70% effective in preventing symptomatic COVID-19. No serious security concerns were reported in the three countries.

The results, released in a press release in November, highlighted that the vaccine could be up to 90% effective if given half the dose for the first shot. However, the group did not disclose that the data was obtained as a result of a dosing error, and scientists later criticized the judging leaders for their lack of transparency and rigor.

Oxford team chief Andrew Pollard told BuzzFeed News that he hoped the paper would raise concerns about the rest of the trial. “It’s mostly assumed that we’ve tried to cherry-pick the data for better results.” “But it is not. We have agreed in advance with the regulators to accept the advance communication. “

Yet, scientists who were confused Before News advertiser Not sure if their concerns have been fully addressed.

“When it comes to policymaking, the 0% figure is hard to explain,” Natalie Dean, a biologist at the University of Florida, told BuzzFeed News, an expert in technique design for testing vaccines against emerging diseases.

“It’s a noise,” John Moore, a virologist at Well Cornell Medical College in New York, who works on developing a vaccine against HIV, told BuzzFeed News. “The vaccine definitely‘ works ’, but we still don’t know how good it is.

The vaccine, developed by Oxford University and its spin-off company Vakitek, is being marketed in collaboration with the British-Swedish pharmaceutical company AstraZeneca. It contains a chimpanzee adenovirus – a group of viruses that can cause colds and coughs in humans – a virus caused by CVVID-19, engineered to make “spike” proteins from SARS-Covi-2.

Scientists and public health officials are anxiously awaiting these results because the Oxford-Astrageneca vaccine is the most widely pre-ordered of the COVID-19 vaccines that the government hopes will eventually bring the epidemic under control.

The application includes the low cost of the vaccine and the ease of delivery. The Oxford-AstraZeneca vaccine will be available at less than ৪ 4 per dose for about অন্যান্য 20 to ২৫ 25 for other vaccines, including the results of large-scale clinical trials by rival drug giants Pfizer and Moderner, according to a supply agreement. Biotech company.

What’s more, the Oxford-Astragenica vaccine can be stored at normal refrigeration temperatures compared to Pfizer and Moderna, which must be deeply frozen until shortly before use – in the case of the Pfizer vaccine At about -70 degrees Celsius.

But claims for the vaccine’s effectiveness have been in the air since November 23, when AstraZeneca issued a Confusing A press release with details of the combined results of a trial involving about 23,000 volunteers conducted by the University of Oxford in the United Kingdom and Brazil. Based on how 131 cases of CVVID-19 were distributed across test vaccines and placebo weapons, Astrageneca claimed A “70% average efficiency.”

This suggests that the vaccine was less effective than its main competitors Pfizer And Modern Each announced in early November that their vaccine tests indicated they were more than 90% effective.

In a twist, however, AstraZeneca and Oxford claimed that their vaccine was also 90% effective, if participants were given half the dose after a full dose. The two full doses, meanwhile, have produced only 62% efficacy. More successful results are characterized by the push of their promotion.

“Interestingly, we have found that one of our dosing systems can be about 90% effective and if this dosing system is used, more people can be vaccinated to deliver the vaccine as planned,” Pollard said in a press release.

Scientists were initially confused by these discoveries. “As presented, it was difficult for me to explain the results,” Dean told BuzzFeed News last week.

As more details of what happened happened, experts became increasingly skeptical of the 90% claim. First Manny Pangalos, Head of Non-Oncology Research and Development, AstraZeneca Admitted to Reuters The half dose was actually the result of an error, first Published in the Mirror magazine Back in June.

Then, on November 24, Monsef Slaui, a leading scientist in Operation Warp Speed, partnered with the U.S. federal government to accelerate the development of the COVID-19 vaccine. Told reporters Volunteers were incorrectly given the initial half-dose that was less than 55 years old – so did not represent the age of the volunteers throughout the trial.

The dosing error that affected a nonprescription group reflects another confusing aspect of the UK judgment: since it was first Listed on ClinicalTrials.gov Towards the end of May, the number of specific patient groups in the experiment was steadily increased, creating a confusing array of different treatments for each of the 12 experimental groups and 25 subgroups.

“What do these judgments mean? We don’t know, ”Moore told BuzzFeed News last week.

In the new Lancet paper, the Oxford team statistically controlled for age differences between groups given different doses, discovering that improved efficacy of half-dose, full-dose treatment remained. But other scientists are concerned about how well it works in older people – with no information yet on the risk of Covid-19.

“It needs further evaluation,” Dean said.

Disliked Pfizer and Modarna, Oxford University and AstraZeneca have not released a complete breakdown of their trial protocols for investigating other researchers at the beginning of their large-scale trial, making it difficult to understand the results presented in an earlier press release. More concerns about transparency were expressed when a UK participant was suspended from vaccine trials after a suspected fatal adverse reaction. The break was only published after it was published in Biomedical News Site Stat.

In a statement sent to BuzzFeed News last week, the Oxford Group noted the significance of the dosing error and said that plans to proceed with the analysis had been made clear to UK regulatory authorities:[W]Hen obviously the lower dose that was used, we discussed it with the regulator and agreed to the plan to test both lower dose / higher dose and higher dose / higher dose, which allows us to include both methods. “

The new paper notes that the protocol was amended on June 5, about a week after the trial began. And Pollard told reporters at a press briefing held today at the Science Media Center in London that the change was made before the “database was locked” for the trial, meaning it was part of an officially approved plan.

Nevertheless, the misleading results do not appear to be acceptable to the FDA. The US regulator is expected to wait for the outcome of another AstraZeneca trial run by Ostford before deciding whether to approve the vaccine for emergency use.

“All I can say is that a lot needs to be done,” Paul Offitt, director of the Vaccine Education Center at Philadelphia Children’s Hospital and a member of the FDA’s Vaccines and Related Organic Products Advisory Committee, told BuzzFeed News last week.

Sloe, a leading scientist at Operation Warp Speed, told reporters on December 2 that it was not clear why “if not there” there was a difference of 2% versus 2% from effectiveness. “A very clear explanation based on the information and data behind what is behind these two numbers may not be enough to approve the package.”

Speaking at a Science Media Center briefing, AstraZeneca CEO Pascal Sariot said he hoped the FDA would seek results as a result of the U.S. trial.

Another concern is that the results are from the UK and have been compiled Brazilian The tests, which were initially conceived as separate tests of vaccine effectiveness, involved somewhat different treatments and placebo weapons. The Oxford Group realized that Britain’s success in cutting the COVID-19 transcription in late spring meant that there were not enough lawsuits to get the right outcome of its UK trial.

Oxford was the team Initially bullish About the possibility of an effective COVID-19 vaccine appearing first. “We’re probably in a place where there is certainly one of the highest levels of covid infection in Europe at the moment, so we have a fair shot at getting effective results over the next three months,” said Adrian Hill, director of the Jenner Institute in Oxford. Told CNN Towards the end of April

However, less than a month later The Telegraph says Newspaper: “This is a fight against the disappearance of the virus and against time. At the moment, there is a 50% chance that we will not get any results. “

This demand is high due to the huge hopes created in the Oxford-AstraZeneca vaccine. This is especially true in the United Kingdom, where Prime Minister Boris Johnson is present Appreciated the work Of “Our Brilliant Scientist” and where no unit in his office presses for dew drops to be vaccinated with Union Jack, According to the Huffington Post.

The barrier to emergency approval of the vaccine in the UK is expected to be lower than in the US. Indeed, the country has regulatory agencies for medicines and healthcare products Already approved Pfizer vaccine, which is still available Is under consideration An advisory panel of the U.S. health agency is meeting this Thursday to evaluate the results of the Pfizer vaccine by the FDA, which is expected to become the first vaccine to receive emergency approval in the United States.

The UK approval of the Oxford-AstraZeneca vaccine could lead to orders being processed, taking into account the cost and availability of the vaccine. According to a Data analysis About 2.7 billion doses have already been ordered from the science journal Nature’s LifeScience analysis company AirFiniti, a significant amount more than any other single vaccine candidate.

Scientists are concerned about questions surrounding the effectiveness of the vaccine, as any problems that arise later could damage confidence in COVID-19 vaccines in general.

“Our biggest collective fear is that things will go wrong that compromises public confidence,” Moore said. “We wanted a process that was as clear as possible.”

Stephanie M. Lee contributed to the reporting of this story.

Source link

Leave a Reply

Your email address will not be published. Required fields are marked *