Pfizer-BioNTech said Thursday that clinical trials of the Covid-19 vaccine are being started in pregnant women, which are the first such trials to include expectant mothers in the US.
The drugmaker aims to enroll about 4,000 pregnant women in the trials, which will include participants in the US as well as Argentina, Brazil, Canada, Chile, Mozambique, South Africa, Spain and the United Kingdom. Women older than 18 and who are 24 to 34 weeks in their pregnancy are eligible.
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The first doses will be administered in the US, Pfizer said.
Dr Brenna Hughes, a medical-fetal medicine specialist at Duke Health in Durham, North Carolina, said she “absolutely applauds” Pfizer’s study on the vaccine in pregnant women.
“Any information to ensure pregnant patients that the vaccine is safe for them is much needed,” said Hughes, a member of the American College of Obstetricians and Gynecologists.
“We are proud to begin this study in pregnant women and continue to gather evidence on safety and efficacy to potentially support the use of the vaccine by important subpopulations,” said Dr. William Gruber, senior vice president of Vaccine Clinical Research at Pfizer, said. in a statement.
Some of the women will get the right shots, while others will get a placebo. They will only know after birth what kind they received. At that point, women who have received the placebo will be offered the vaccine.
Researchers will monitor for any adverse side effects in women, including miscarriage. There are some preliminary data on safety during pregnancy, as some women in previous studies of the Covid-19 vaccine became pregnant while participating in clinical trials.
“Of all the things we’re seeing so far from pregnant women who have had the vaccine, there are no red flags,” said Stacey Stewart, president of the March of Dimes.
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However, there is evidence that Covid-19 itself can harm harmful mothers.
According to the Centers for Disease Control and Prevention, pregnant women who become infected with SARS-CoV-2, the virus that causes Covid-19, have an increased risk of complications, including premature birth and the need to sit in a ventilator. .
“We’re in a pandemic,” Hughes said. “We are not really in a situation where we can take the risk, and in my opinion we cannot offer the vaccine to every potential person who can benefit from it.”
There is currently no clear guidance from the CDC on whether pregnant women should get the Covid-19 vaccine. The agency says women “can choose to be vaccinated.”
Pfizer’s study will follow newborns six months after birth to see if antibodies are transferred from the mother to the babies.
There is precedent for such protection. Babies born to women who have had the flu shot have some protection against the flu for at least six months until they can also receive the vaccine.
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