Thinking About Health: Reports about coronavirus vaccine don't always give the full story
Last updated 6/11/2020 at 4:13pm
How soon will there be a vaccine to protect people from the coronavirus? That’s the question uppermost on the minds of many Americans, especially the elderly and others especially at risk for a severe bout of the disease. Everyone wants the vaccine yesterday. Maybe that’s why the media cheered in late May and hope soared when Moderna, a 10-year-old biotechnology company based in Cambridge, Massachusetts, issued a news release with hopeful information.
Positive Phase 1 data, although early, showed promising results, the company said: “These data substantiate our belief that mRNA-1273 (the vaccine name) has potential to prevent COVID-19 disease.”
Given how devastating the disease has been, who wouldn’t appreciate news like that? The media ran with the story. The company’s stock value zoomed up even though Moderna has yet to sell any products. The public was left with the message that maybe a vaccine was right around the corner. But is it?
Readers and listeners need to be on the lookout for clues to the real story right now.
Helen Branswell, a veteran reporter I know who has covered other disease outbreaks and knows her stuff, penned a cautionary message for STAT News where she now works.
She said, “While Moderna blitzed the media, it revealed very little information, and most of what it did disclose were words, not data. With science, numbers speak louder than words.”
I reached Branswell by phone to chat about how people should judge the studies, the claims and the wishful thinking that will surely come until a new medication has been discovered that could tame the virus.
First off, the public needs to understand that all clinical trials are not created equal. A Phase 1 trial that Moderna reported is just the first step in the process. These trials are usually small with no expectation there will be data about how effective a drug will be. Instead, Branswell pointed out, such a trial is “really about establishing a dose to make sure it’s safe enough to keep going.”
In a Phase 2 trial, which may enroll a few hundred people, researchers are looking for efficacy and safety signals that tell them whether it makes sense to continue and whether the result may be an effective vaccine for humans.
Phase 3 trials are the gold standard. They are usually large and double blind, which means half of the participants receive the trial vaccine and the other half a placebo. Neither the participants nor the researchers know which half is which until the end of the trial. It’s generally best to look for how well a new drug performed in a Phase 3 trial with results published in a peer-reviewed journal where experts have scrutinized the data.
In this case, because of the rush to find a vaccine, Branswell said some testing may be compressed. For example, a Phase 1 trial may be combined with a Phase 2 trial in the hope of speeding up the process and getting quickly to a marketable vaccine.
Branswell told me many things are still not known about the virus. For example, she said, “It’s still not clear what protective immunity should look like and what level of antibodies are needed to ward off disease.”
When science produces answers to questions like those, then ideally, results of Phase 3 trials should be published in peer-reviewed journals where experts have a chance to “kick the tires” and cast a critical eye on the data. If a new therapeutic drug passes the test, then it is considered fit for humans.
Moderna’s vaccine in the making “may be effective,” Branswell said. “But we don’t know yet. It’s too soon. People don’t understand it takes time to produce a vaccine.”
So what does the vaccine universe look like now? Eight vaccine candidates are in human trials, and more than 100 others are ongoing with some in animal testing. Given the urgency to find a vaccine, news releases similar to Moderna’s will undoubtedly find their way into the hands of journalists. The public needs to read them skeptically.
The same goes for news stories built around a single source or an animal study or a study that doesn’t mention a control group or is built on a “preprint.” These are essentially rough drafts of studies that have not been peer reviewed.
“Results of these studies should not be reported by the media as established information,” Gary Schwitzer, the longtime publisher of Health News Review, said. “Questions about the quality of the evidence are more important than ever before.”
Do you have a question about the efforts to develop a vaccine against the coronavirus? Write to Trudy at [email protected]