Vaccines are among the safest medical products in the world—but only because of the intense rigour of the clinical trials that test their safety and effectiveness
MOSCOW, RUSSIA - AUGUST 12, 2020: Ampoules with a COVID-19 vaccine developed by the Gamalei Scientific Research Institute of Epidemiology and Microbiology of the Russian Healthcare Ministry. Gam-COVID-Vac is a vector two-component adenovirus based vaccine. The vaccine will be available to general public on January 1, 2021. Image: Mikhail Japaridze\TASS via Getty Images
(Matter) When Vladimir Putin announced Tuesday that Russia had approved a coronavirus vaccine — with no evidence from large-scale clinical trials — vaccine experts were worried. “I think it’s really scary. It’s really risky,” said Daniel Salmon, the director of the Institute for Vaccine Safety at Johns Hopkins University. Salmon and other experts said that Russia is taking a dangerous step by jumping ahead of so-called Phase 3 trials, which can determine that the vaccine works better than a placebo and doesn’t cause harm to some people who get it. Unlike experimental drugs given to the sick, vaccines are intended to be given to masses of healthy people. So they must clear a high bar of safety standards. If hundreds of millions of people get a vaccine, even a rare side effect could crop up in thousands of people. Over the course of the past century, researchers have developed increasingly powerful ways to test vaccines for safety and effectiveness. Some of those lessons were learned the hard way, when a new vaccine caused some harm. But vaccines are now among the safest medical products in the world, thanks to the intense rigor of the clinical trials tracking their safety and effectiveness. This testing typically begins before a single person has received a new vaccine, when researchers inject it into mice or monkeys to see how they respond. If those animal studies turn out well, researchers then enlist a few dozen volunteers for a Phase 1 trial, in which all volunteers get the experimental vaccine. Doctors typically keep these volunteers under observation to make sure they don’t have any immediate negative reactions, and to see whether they make antibodies against a pathogen. It’s not uncommon for people to feel achiness in their muscles or even a mild fever, but these mild symptoms typically don’t last long. If Phase 1 trials do not turn up serious safety problems, then researchers usually move to a Phase 2 trial, in which they inject hundreds of people and make more detailed observations. The first clinical trials on coronavirus vaccines started in March, and now there are 29 underway, with more to launch soon. Companies such as AstraZeneca, Moderna, Novavax and Pfizer are beginning to share optimistic early results: So far, they have only detected mild or moderate symptoms and no severe side effects. Volunteers have also produced antibodies to the coronavirus, in some cases more than are produced by people who have recovered from an infection. But no matter how promising these early results, Phase 3 trials can fail. The timing of Russia’s announcement makes it “very unlikely that they have sufficient data about the efficacy of the product,” said Natalie Dean, a biostatistician and infectious disease expert at the University of Florida who has warned against rushing the vaccine-approval process. Dean noted that even vaccines that have produced promising data from early trials in humans have flopped at later stages. In a large, randomized control trial, researchers give the vaccine or a placebo to tens of thousands of people, and wait for them to encounter the virus in the real world. “Then you wait to see, do they get sick or not. Do they die or not?” said Dr. Steven Black, a vaccine expert with the Task Force for Global Health. If a vaccine is effective, fewer vaccinated volunteers will get sick than the ones who received the placebo. The Russian researchers have not yet begun that crucial test. In June, the Gamaleya Research Institute of Epidemiology and Microbiology at the Health Ministry of the Russian Federation registered a combined Phase 1 and 2 trial on a vaccine called Gam-COVID-Vac Lyo. The researchers planned to test it on 38 volunteers. They said that the vaccine was made from an adenovirus — a harmless cold virus — carrying a coronavirus gene, similar to what AstraZeneca and Johnson & Johnson are using in their vaccines. The technology is still relatively new: The first adenovirus vaccine for any disease was approved for Ebola in June. Since then, Russian officials have claimed that they would be moving the vaccine quickly into manufacturing. Putin’s announcement Tuesday made it official. Yet the institute has never published its Phase 1 and 2 trial data. At Putin’s announcement, Russia’s Minister of Health, Mikhail Murashko, declared that “all the volunteers developed high titers of antibodies to COVID-19. At the same time, none of them had serious complications of immunization.” That is the sort of result you’d expect from a Phase 1 trial. It doesn’t tell you if the vaccine actually works. “This is all beyond stupid,” said John Moore, a virologist at Weill Cornell Medical College in New York City. “Putin doesn’t have a vaccine, he’s just making a political statement.” On Tuesday, the Russian institute put up a website claiming that a Phase 3 trial would begin the next day involving more than 2,000 people in Russia as well as the United Arab Emirates, Saudi Arabia, Brazil and Mexico. All other Phase 3 trials of coronavirus vaccines currently underway are more than 10 times larger than that, with 30,000 volunteers apiece. Dr. Nicole Lurie, a former assistant secretary for preparedness and response at the U.S. Department of Health and Human Services and an adviser at the Coalition for Epidemic Preparedness Innovations, said the lesson that the U.S. government should draw from Putin’s announcement is clear. “This is exactly the situation that Americans expect our government to avoid,” she said. A faster process©2019 New York Times News Service