Testing Vaccines

The Covid-19 pandemic has affected the lives of nearly everyone in the world. But for 15-year-old Isabella Stiles, who lives in Bardstown, Kentucky, it hit particularly close to home. Her father, Matthew, is a doctor who practices family medicine. He was repeatedly exposed to the virus that causes Covid-19 while treating sick patients. Each time that happened, Isabella’s dad had to quarantine for two weeks, separated from his family to make sure he didn’t pass the virus on to them.

As of February 3, 2021, more than 26.5 million people in the U.S. had become infected with the virus that causes Covid-19 and more than 447,000 had died. When Isabella learned that teens and preteens could help test an experimental vaccine that might protect people from developing Covid-19, she considered joining the study. After much discussion, Isabella and her family decided that she could participate. “When this is all over, I can feel like I did something to help end the pandemic,” says Isabella.

The Covid-19 pandemic has affected nearly everyone in the world. But it hit especially close to home for 15-year-old Isabella Stiles. She lives in Bardstown, Kentucky. Her father, Matthew, is a doctor who practices family medicine. He was exposed to the virus that causes Covid-19 over and over, because he treated sick patients. Each time that happened, Isabella’s dad had to quarantine for two weeks. He stayed away from his family so he couldn’t pass the virus on to them.

By January 27, 2021, the virus that causes Covid-19 had infected more than 25.5 million people in the U.S. More than 425,000 had died. Isabella learned that teens and preteens could help test an experimental vaccine. It might protect people from developing Covid-19. Isabella considered joining the study. She and her family discussed the idea and decided that she could take part. “When this is all over, I can feel like I did something to help end the pandemic,” she says.

The vaccine Isabella would test is produced by the pharmaceutical companies Pfizer and BioNTech and relies on a new technology: messenger RNA, or mRNA (see How an mRNA Covid-19 Vaccine Works). Scientists have been studying mRNA technology for more than 30 years. When Covid-19 started to spread, companies realized that mRNA could be used to rapidly produce a vaccine against SARS-CoV-2, the virus that causes Covid-19.

To make sure a new treatment is safe and effective, companies carry out a series of clinical trials, or research studies that involve people. Each trial has three phases. Phase I tests the new treatment for safety on a small number of people. Phase II involves several hundred people and tests how well the vaccine works. Phase III, the final and largest phase, includes thousands of participants. The large sample size allows researchers to assess how effective a treatment is.

More than 44,000 adults participated in Phase III of Pfizer- BioNTech’s trial, which showed that the vaccine was 95 percent effective at preventing people from becoming ill with Covid-19. Once the new vaccine was deemed safe in adults, Pfizer-BioNTech expanded testing to more than 2,200 teens and preteens.

Isabella would test a vaccine made by the pharmaceutical companies Pfizer and BioNTech. It uses a new technology called messenger RNA, or mRNA (see How the New Covid-19 Vaccine Works). Scientists have been studying mRNA technology for more than 30 years. When Covid-19 started to spread, companies realized that mRNA could help. They could use it to quickly produce a vaccine against SARS-CoV-2, the virus that causes Covid-19.

Companies must make sure a new treatment is safe and effective. So they carry out a series of clinical trials. These research studies involve people. Each trial has three phases. Phase I tests the new treatment for safety on a small number of people. Phase II involves several hundred people. It tests how well the vaccine works. Phase III is the final and largest phase. It includes thousands of volunteers. With this large sample size, researchers can tell how effective a treatment is.

More than 44,000 adults joined Phase III of Pfizer-BioNTech’s trial. The results showed that the vaccine was extremely effective. It reduced people’s chances of getting Covid-19 by 95 percent. The new vaccine proved safe in adults. Next, Pfizer-BioNTech started testing teens and preteens.

According to the American Academy of Pediatrics (AAP), in the U.S. alone, roughly 2.5 million kids under the age of 18 have tested positive for Covid-19. Most children don’t suffer as severely from the illness as many adults do. Oftentimes, kids don’t even experience symptoms. But the AAP says 1.3 percent of children suffering from Covid-19 have had serious complications from the disease, and about 0.01 percent have died. Young people can also transmit the virus to those who are more vulnerable, like parents, grandparents, and community members. That’s why pharmaceutical companies asked young people to volunteer for Covid-19 vaccine trials—because they may want to get vaccinated too.

Before any hospital could begin enrolling participants, though, its institutional review board had to determine whether the benefits of the study outweighed the risks. “If it’s not something we would give to our own children, we wouldn’t participate,” says Marty Osbourn, a nurse and research director at Kentucky Pediatric/Adult Research (KPAR) in Bardstown, which hosted the vaccine trial Isabella joined.

About 2.5 million kids under age 18 have tested positive for Covid-19 in the U.S., says the American Academy of Pediatrics (AAP). Many adults suffer serious symptoms from the illness, but most children don’t. Often, kids don’t even get symptoms. But the AAP says 1.3 percent of children with Covid-19 have had serious complications from the disease. About 0.01 percent of them have died. Young people can also spread the virus to those at greater risk. Parents, grandparents, and community members can get it from them. So kids will need to get vaccinated too. That’s why pharmaceutical companies asked young people to join Covid-19 vaccine trials.

But a hospital couldn’t just start signing up volunteers. First, its institutional review board had to consider the study. Would the benefits outweigh the risks? “If it’s not something we would give to our own children, we wouldn’t participate,” says Marty Osbourn. She’s a nurse and research director at Kentucky Pediatric/Adult Research (KPAR) in Bardstown. Isabella joined the vaccine trial there.

Before the trial, Isabella learned that not all participants would get the new medication. Half would receive a placebo. But volunteers wouldn’t be told who got this inactive substance and who got the real vaccine. That’s because researchers didn’t want this information to influence how volunteers behaved. Comparing how many people in the two groups become sick with Covid-19 allows scientists to figure out how well the vaccine works.

Pfizer- BioNTech’s mRNA vaccine requires two doses. During Isabella’s first visit to KPAR, she got her first injection. Three weeks later, she returned for a second one. After both doses, she used an app to record possible side effects, like fever or chills. Pfizer- BioNTech will continue to monitor the health of all study participants for two years.

Not all volunteers would get the new vaccine. Isabella learned this before the trial. Half would receive a placebo. But volunteers wouldn’t know if they got this inactive substance or the real vaccine. That’s because researchers didn’t want this information to affect the volunteers’ behavior. Scientists compare how many people in the two groups become sick with Covid-19. That allows them to figure out how well the vaccine works.

Pfizer-BioNTech’s mRNA vaccine requires two doses. Isabella got her first shot during her first visit to KPAR. Three weeks later, she returned for a second one. After both doses, she watched for possible side effects, like fever or chills. She recorded them with an app. Pfizer-BioNTech will keep track of all study volunteers’ health for two years.