Pfizer said Monday that early results from its coronavirus vaccine suggest the shots may be a surprisingly robust 90 per cent effective at preventing Covid-19, putting the company on track to apply later this month for emergency-use approval from the Food and Drug Administration.
New Zealand has already secured a deal for enough doses for 750,000 people here, subject to requirements.
"Today is a great day for science and humanity," Albert Bourla, Pfizer's chairman and chief executive, said.
"We are reaching this critical milestone in our vaccine development program at a time when the world needs it most with infection rates setting new records, hospitals nearing over-capacity and economies struggling to reopen."
The announcement, less than a week after an election seen as a referendum on US President Donald Trump's handling of the crisis, was a rare and major piece of encouraging news lately in the battle against the scourge that has killed more than 1.2 million people worldwide, including almost a quarter-million in the United States alone.
"We're in a position potentially to be able to offer some hope," Dr Bill Gruber, Pfizer's senior vice president of clinical development, told the Associated Press. "We're very encouraged."
Dr Anthony Fauci, the US government's top-infectious disease expert, said the results suggesting 90 per cent effectiveness are "just extraordinary," adding: "Not very many people expected it would be as high as that."
"It's going to have a major impact on everything we do with respect to Covid," Fauci said as Pfizer appeared to take the lead in the all-out global race by pharmaceutical companies and various countries to develop a well-tested vaccine against the virus.
Last month, the New Zealand Government announced it had secured a pre-purchase agreement with the vaccine's makers, subject to the completion of trials and it meeting New Zealand regulations.
It could mean New Zealand receiving 1.5 million doses - enough for 750,000 people - as early as the first part of next year.
Research, Science and Innovation Minister Megan Woods said vaccine delivery to New Zealand could be as early as the first quarter of 2021.
"Provided the vaccine is approved for use in New Zealand by Medsafe, it is possible that some doses will be available to us in the first part of 2021," she said.
"Medsafe is working to optimise its processes so that any promising vaccines will be fully assessed as quickly as possible against the same criteria used for all other medicines that enter New Zealand."
Woods said the agreement with Pfizer and BioNTech was one of a number of negotiations underway as part of our portfolio approach, and "good progress" is being made in other purchasing negotiations.
"The additional agreements will ensure that once the portfolio is completed, we will have sufficient Covid-19 vaccines for the whole population."
The Ministry of Health was developing a sequencing framework to guide the rollout of the vaccines as they become available.
When it came to who would be prioritised, three groups were being considered: those at risk of spreading Covid-19, those at risk of contracting it, and those at risk of increased morbidity and mortality.
"Ensuring equity of outcomes is a key measure of success, including protection for Māori, Pacific peoples and our most vulnerable population groups, such as older people, disabled people, health workers, essential workers and border staff," she said.
"The Government has set aside $66.3m for medical supplies and infrastructure to ensure New Zealand is ready to launch a Covid-19 Immunisation Programme as soon as we have a safe and effective vaccine."
Otago University clinical microbiologist Professor David Murdoch said the reported level of effectiveness by Pfizer was "certainly very encouraging" and is higher than many would have anticipated.
"However, this is not the final analysis of the study, which is planned when a total of 164 confirmed Covid-19 cases have been recorded," he said.
"Once these final results are available and peer-reviewed we will have a more precise estimate of the vaccine's effectiveness, as well as detailed information on safety and how effective the vaccine is against severe disease. We also do not know yet how long immunity will last following vaccination."
Murdoch said the vaccine was also of great interest to the scientific community because it used a completely new technology, injecting the SARS-CoV-2 virus's genetic code in order to train the immune system.
Dr Bruce Aylward, the World Health Organisation's senior adviser, said that the vaccine could "fundamentally change the direction of this crisis" by March, when the UN agency hopes to start vaccinating high-risk groups.
Still, Monday's announcement doesn't mean for certain that a vaccine is imminent: This interim analysis, from an independent data monitoring board, looked at 94 infections recorded so far in a study that has enrolled nearly 44,000 people in the US and five other countries. Some participants got the vaccine, while others got dummy shots.
Pfizer Inc. cautioned that the protection rate might change by the time the study ends. Even revealing such early data is highly unusual.
Dr Jesse Goodman of Georgetown University, former chief of the FDA's vaccine division, called the partial results "extremely promising" but ticked off many questions still to be answered, including how long the vaccine's effects last and whether it protects older people as well as younger ones.
Also, whenever a vaccine does arrive, initial supplies will be scarce and rationed, with priority likely to be given to health care workers and others on the front lines. Pfizer has estimated that 50 million doses of its two-shot vaccine could be available globally by the end of 2020, which could cover 25 million people.
Global markets, already buoyed by the victory of President-elect Joe Biden, exploded on the news from Pfizer. The S&P 500 surged 3.7 per cent after the opening bell, and the Dow Jones Industrial Average was up more than 1300 points. Pfizer jumped more than 9 per cent. Other vaccine stocks were up as well.
Trump, who had suggested repeatedly during the presidential campaign that a vaccine could be ready by Election Day, tweeted: "STOCK MARKET UP BIG, VACCINE COMING SOON. REPORT 90% EFFECTIVE. SUCH GREAT NEWS!"
Confirmed infections in the US were expected to eclipse 10 million on Monday, the highest in the world. Cases in the United States are running at all-time highs of more than 100,000 new ones per day.
The timing of Pfizer's announcement is likely to feed unsubstantiated suspicions from Trump supporters that the pharmaceutical industry was withholding the news until after the election. Donald Trump Jr. tweeted: "The timing of this is pretty amazing. Nothing nefarious about the timing of this at all right?"
Pfizer CEO Bourla said on CNBC that the election was always an artificial deadline and that the data was going to be ready when it was ready. The independent data monitors met on Sunday, analyzing the Covid-19 test results so far and notifying Pfizer.
"I am very happy," Bourla said, "but at the same time, sometimes I have tears in my eyes when I realise that this is the end of nine months, day-and-night work of so many people and how many people, billions, invested hopes on this."
He added: "I never thought it would be 90 per cent."
Scientists have warned for months that any Covid-19 shot may be only as good as flu vaccines, which are about 50 per cent effective and require yearly immunisations. Earlier this year, Fauci said he would be happy with a Covid-19 vaccine that was 60 per cent effective.
Pfizer opted not to join the Trump administration's Operation Warp Speed, which helped a half-dozen drugmakers accelerate their vaccine testing and helped fund the work. Instead, Pfizer funded all its testing and manufacturing costs itself. The company said it has invested billions of dollars.
The president's boasts that a vaccine could be ready before Election Day raised fears that the Trump administration might pressure regulators and scientists to cut corners for political gain. After the first presidential debate, Bourla told his employees he was disappointed their work was being dragged into political debates and pledged the company was "moving at the speed of science".
The shots, made by Pfizer and its German partner BioNTech, are among 10 possible vaccine candidates in late-stage testing around the world — four of them so far in huge studies in the US Another US company, Moderna Inc., also hopes to file an application with the FDA this month.
Volunteers in the final-stage studies, and the researchers, don't know who received the real vaccine or a dummy shot. But a week after their second dose, Pfizer's study began counting the number who developed Covid-19 symptoms and were confirmed to have the coronavirus.
Because the Pfizer study hasn't ended, Gruber couldn't say how many in each group had infections. But the math suggests that almost all the infections counted so far had to have occurred in people who got the dummy shots.
Pfizer doesn't plan to stop its study until it records 164 infections among all the volunteers, a number that the FDA has agreed is enough to tell how well the vaccine is working. The agency has made clear that any vaccine must be at least 50 per cent effective.
No participant so far has become severely ill, Gruber said. He could not provide a breakdown of how many of the infections had occurred in older people, who are at highest risk from Covid-19.
Participants were tested only if they developed symptoms, leaving unanswered whether vaccinated people could get infected but show no symptoms and unknowingly spread the virus.
Fauci said that the Pfizer vaccine and virtually all others in testing target the spike protein the coronavirus uses to infect cells, so the latest results validate that approach.
Public Citizen, the consumer advocacy group, called the release of the preliminary and incomplete data "bad science" and said that any enthusiasm over the results "must be tempered" until they are reviewed by the FDA and its independent experts.
"Crucial information absent from the companies' announcement is any evidence that the vaccine prevents serious Covid-19 cases or reduces hospitalisations and deaths due to the disease," the organisation said.
FDA has told companies they must track half their participants for side effects for at least two months, the period when problems typically crop up. Pfizer expects to reach that milestone later this month.
Because the pandemic is still raging, manufacturers hope to get permission from governments around the world for emergency use of their vaccines while additional testing continues. That would allow them to get their vaccines to market faster, but it also raises safety concerns.
- AP
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