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The coronavirus is spreading uncontrollably in the United States, overwhelming healthcare systems and killing more than 1,100 Americans a day. But there is a small silver lining: It is accelerating the testing of vaccines that could eventually end the pandemic.
The rising virus has already enabled Pfizer and Moderna to speed up testing of their vaccines, which appear to be very effective in preventing Covid-19.
Read | Pfizer completes Covid-19 trial 95% effective, to request emergency use authorization
And if, as seems inevitable, the virus continues to proliferate – it is spreading faster than ever in the United States and some other countries – it is likely to accelerate evaluations of promising vaccine candidates from other drug companies.
“We’re seeing something apocalyptic in terms of the level of transmission in the country right now,” said Dr. Peter Hotez, a vaccine scientist at the National School of Tropical Medicine at Baylor College of Medicine. “Unfortunately, this pandemic is still spreading and that provides many opportunities to look at the efficacy of the vaccine.”
Over the past week, an average of more than 158,000 new coronavirus cases were confirmed each day in the United States. More than 159,000 were reported Tuesday.
In late-stage vaccine trials, the faster participants get sick, the faster drug developers get enough data to know if their vaccines are effective.
Researchers determine how well a vaccine works by comparing the rate at which volunteers who receive a placebo get sick with the rate at which those who receive a vaccine. If the vaccine offers strong protection, the number of people who get the placebo and then get sick will far exceed the number of vaccinated people who get sick.
The trials are designed so that once a certain number of participants contract Covid-19, an independent panel of experts will carry out a preliminary examination of the data. (Other factors, such as how long it has been since participants were vaccinated, can also play a role.)
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The trial ends after a certain number of cases, between 150 and 170, have accumulated. That number is chosen to ensure that the results have enough statistical power to tell how well the vaccine works.
Pfizer announced Wednesday that its vaccine was 95% effective and had no serious side effects. The company, along with its German partner BioNTech, reached those findings after 170 participants in its trials, the vast majority receiving a placebo, contracted Covid-19.
The news came just a week after a preliminary analysis found that Pfizer’s vaccine was more than 90% effective. That data was analyzed after 94 participants contracted COVID-19, nearly three times the amount the company had originally planned, which would initiate an early look at the vaccine’s effectiveness.
The same phenomenon helped Moderna, which announced Monday that a preliminary analysis had found its vaccine to be 94.5% effective. The company had planned to need only 53 cases of Covid-19 to appear in its test before experts took a first look at the data. But the rise in infections nationwide helped Moderna exceed that number: The results were based on 95 sick participants.
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The relatively large number of sick people in the trials, along with the apparent effectiveness of the vaccines, could help boost public confidence.
“It will be hard enough to convince people to take this vaccine as is,” said Geoffrey Porges, an analyst at investment bank SVB Leerink. “So the more confident you can be, by virtue of having more statistical power, by virtue of having more events, then that should go somewhere.”
In the coming weeks and months, the worsening pandemic could make the results of other closely followed trials, such as one for a vaccine developed by Johnson & Johnson and another by AstraZeneca and the University of Oxford, available sooner and more. statistical power.
The fast-growing pandemic could also speed up trials of treatments for Covid-19.
The pharmaceutical company Regeneron, for example, is testing the antibody treatment that President Donald Trump received after contracting Covid-19. A company spokeswoman said enrollment in its trial – the participants are Covid-19 patients who have not been hospitalized – had sped up slightly this month.
Even if the bleak US situation finally helps make vaccines and treatments available sooner, the country would have been much better off if it had kept the pandemic under control, public health experts said.
“This is not how anyone would want it to develop,” said Natalie Dean, a biostatistician and an expert in vaccine trial design at the University of Florida. “I’d rather be South Korea,” which has been keeping the virus at bay since the beginning of the year, he said.
Vaccines are unlikely to be widely available for months. By then, the coronavirus will likely have killed tens of thousands of additional Americans.
Pfizer and Moderna have been waiting to see if any side effects show up in participants before the companies submit their data to the Food and Drug Administration for authorization to distribute the vaccines. Once the FDA gives them the green light, manufacturers will have to increase production and work with governments to distribute the vaccines. Initially, the vaccines will be available only to healthcare workers and other vulnerable groups. When vaccines are widely available, it is unclear whether their protection will last for months, years, or decades.
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Hoping to speed up their testing, drug makers have been setting up trials in Covid-19 hot spots around the world, not just in the United States.
In China, where the virus was rampant earlier this year, new cases have been reduced to a minimum. As a result, Chinese vaccine manufacturers are conducting late-stage trials of their candidates in countries such as the United Arab Emirates, Morocco, Argentina and Peru.
Maryland-based Novavax, which is developing one of 12 vaccines that are in the final phase of clinical trials, has enrolled more than 9,000 participants in Britain since starting a phase 3 trial there in September. Novavax president of research and development, Dr. Gregory Glenn, told analysts last week that he was “feeling very good about our ability to collect cases.”
Britain reported more than 20,000 new cases on Tuesday, part of an increase that rebounded in early October.
Glenn added: “If you’re in the right place at the right time, you can rack up cases very quickly. I think we are in the right place at the right time in the UK. “
Novavax plans to begin a phase 3 trial in the United States this month.
Vaccine developers select different parts of the world for testing for various reasons. They must ensure that the vaccine has been tested in populations that reflect the diversity of the world. They must also ensure that they can enroll participants in regions where the virus is spreading.
“What is initially a hot spot will not necessarily remain a hot spot,” said the Dean of the University of Florida, who has studied how to make clinical trials flexible enough to function during epidemics.
Johnson & Johnson is testing a version of its vaccine in the United States and other countries. The trials, which are set up or planned in more than 200 locations around the world, including 30 states, were chosen in part by modeling the numbers of cases in different regions, said Jake Sargent, a spokesman for the company.
Johnson & Johnson announced Monday that it had begun another trial of its vaccine, testing two doses instead of one. The company aims to enroll 30,000 participants in Belgium, Colombia, France, Germany, the Philippines, South Africa, Spain, Great Britain and the United States. Johnson & Johnson said the locations were chosen “in countries and areas with high incidence of Covid-19.”
