Advertisement
Supported by
Vaccines are among the safest medical products in the world, but due to the intense rigor of clinical trials that prove their protection and efficacy.
By Carl Zimmer
When Vladimir Putin announced Tuesday that Russia had approved a coronavirus vaccine, evidence of large-scale clinical trials, vaccine experts were concerned.
“I think it’s scary. It’s risky,” said Daniel Salmon, director of the Institute for Vaccine Safety at Johns Hopkins University.
Dr. Salmon and other experts said Russia is taking a harmful step towards so-called Phase 3 trials, which can make the vaccine work better than a placebo and not harm other people who receive it.
Unlike experimental medicines given to patients, vaccines are intended to be given to a large number of healthy people, so they will have to cross a higher threshold of protection standards, if millions of people are vaccinated, even in a rare respect.The effect can occur in thousands of other people.
Over the past century, researchers have developed difficult strategies to test the protection and efficacy of vaccines.Some of these classes have been learned the hard way, when a new vaccine has caused damage.But vaccines are now among the safest medical products in the world thanks to the intense rigor in clinical trials to control their protection and efficacy.
These tests begin before an unmarried user has won a new vaccine, when researchers inject it into mice or monkeys to see how they react.
If those animals do well, the researchers then recruit a few dozen volunteers for a Phase 1 trial, in which all volunteers get the experimental vaccine.
Sometimes doctors keep those volunteers under control to make sure they don’t have immediate negative reactions and to see if they’re producing antibodies opposed to a pathogen.symptoms regularly don’t last long.
While phase 1 trials do not pose serious protective problems, researchers move on to a phase 2 trial, in which they inject a lot of other people and make more detailed observations.
The first clinical trials of coronavirus vaccines began in March, and there are now 29 in progress, and more will soon be released.only mild or moderate symptoms and no serious side effects.Volunteers also produced antibodies opposed to coronavirus, in some cases more than those produced by others who recovered from the infection.
But as promising as those initial effects may be, Phase 3 trials may fail.
The timing of Russia’s announcement makes it “very knowledgeable about the effectiveness of the product,” said Natalie Dean, a biostatistics and infectious disease specialist at the University of Florida, who warned of the rush of the vaccine approval process.. Dean noted that even vaccines that produced promising knowledge of early human trials failed in later stages.
In a giant randomized controlled trial, researchers administer the vaccine or placebo to tens of thousands of people and wait for them to find the virus in the real world.
Advertisement