Pfizer, BioNTech start testing Covid-19 vaccine in pregnant women

Dr. William Gruber, senior vice president of vaccine clinical research and development for Pfizer, said in an interview the company could have results by the fourth quarter of 2021.

Gruber said data so far suggest that pregnant women with COVID-19 have higher rates of severe disease. They also have higher rates of pregnancy complications, such as premature birth, compared with pregnant women not infected by the coronavirus.

That increased risk is why U.S. regulators and public health advisers “are interested in doing this in the first place – so people can be fully informed about the safety profile,” he said.

Last week, the U.S. National Institutes of Health called for greater inclusion of pregnant and lactating women in COVID-19 vaccine research.

Bioethicists, vaccine and maternal health experts have argued for years that pregnant women should be included early in trials of pandemic vaccines so they would not need to wait until long after a successful one emerges.

FILE PHOTO: A medical worker fills a syringe with a dose of the Pfizer-BioNTech coronavirus disease (COVID-19) vaccine as Japan launches its inoculation campaign, at Tokyo Medical Center in Tokyo, Japan February 17, 2021. Behrouz Mehri/Pool via REUTERS/File Photo

Nevertheless, pregnant women were excluded from the large U.S. trials used to obtain emergency use authorization of COVID-19 vaccines.

Drugmakers have said they first need to make sure the vaccines are safe and effective more generally.

In the United States, regulators require drugmakers to conduct safety studies in pregnant animals before vaccines are tested in pregnant women to ensure they do not harm the fetus or lead to a miscarriage. The companies said those studies revealed no new risks.

Pregnant women in the United States have already received their first doses, the companies said.