Pregnant Women Should Be a Priority When It Comes to Vaccination R&D, New Report Urges

December 10, 2018
Alexandra Ward

Pregnant women have been routinely excluded from the vaccination research and development process, even though this vulnerable class is sometimes uniquely affected by infectious disease outbreaks.

Pregnant women have been routinely excluded from the vaccination research and development process, even though this vulnerable class is sometimes uniquely affected by infectious disease outbreaks.

In an effort to address and correct this inequity in vaccination coverage, a new report by the Pregnancy Research Ethics for Vaccines, Epidemics, and New Technologies (PREVENT) Working Group, titled Pregnant Woman & Vaccines Against Emerging Epidemic Threats: Ethics Guidance for Preparedness, Research and Response, is urging vaccination researchers, policymakers, and health groups across the globe to embark on a “paradigm shift” and change the default thinking when it comes to maternal vaccination.

Inclusion of pregnant women in vaccine research and development should be the default, not the exception, the group, funded by Wellcome Trust and made up of 17 multidisciplinary members, explained.

“There is nothing about pregnancy that makes women immune from infectious disease threats, and many infections pose increased risks to pregnant women themselves, the developing fetus, and usually both,” Carleigh Krubiner, PhD, a lead author of the report appointed at the Johns Hopkins Berman Institute of Bioethics and the Center for Global Development, told Contagion®. “[W]hen we’re developing vaccines to combat these infectious disease threats, we need to be considering pregnant women as part of the target population—when investment decisions are made and as we conduct the research to understand safety, immunogenicity, and ultimately, effectiveness.”

The report contains 22 recommendations—ranging from calls for more funding and investments, to the identification of global stakeholders, to more efficient communication of study findings—and specifies public health community targets for each item.

“We’ve had an incredibly positive response. We are excited,” Ruth R. Faden, PhD, MPH, lead author of the report and founding director of the Johns Hopkins Berman Institute of Bioethics, told Contagion® in an interview. “Pretty much no one is happy with the situation with Ebola right now. How could you feel good about the fact that pregnant women and lactating women are not being allowed a chance to save their lives? It’s a horrible dynamic, but it’s not a new phenomenon. It just wasn’t top of mind. There’s been an insidious and unconscious sort of failure to think about pregnant women in vaccine research and development.”

Although there are unique ethical issues surrounding the vaccination of pregnant women, namely the effects on the fetus, recent outbreaks have demonstrated that women and children, in particular, are sometimes disproportionately affected by epidemics.

As Dr. Faden mentioned, the current Ebola virus outbreak in the Democratic Republic of the Congo is a good example. According to a World Health Organization (WHO) update issued last week, in cases to date, females accounted for 62% of overall cases where sex was reported and, of those women, 18 were pregnant.

Merck’s VSV-EBOV vaccine, which contains the live virus, has been highly effective in taming the outbreak, but pregnant women and women who are breastfeeding cannot receive it because of safety concerns, according to the Center for Infectious Disease Research and Policy at the University of Minnesota.

Lassa fever is another infectious disease that is “especially devastating” to pregnant women in the third trimester, Dr. Krubiner pointed out.

“There is now a lot of activity to develop vaccines against Lassa fever, one of the WHO priority pathogens under the research and development (R&D) blueprint,” she told Contagion®. “[There are] extremely high rates of maternal death and fetal loss. We need to be proactive in considering pregnant women as one of the key target populations of Lassa fever vaccines and developing an appropriate evidence base so that they can be protected during future outbreaks.”

Zika, too, brought the issue of maternal vaccination to the forefront of the public consciousness.

“Zika galvanized the imagination of the vaccine community,” Dr. Faden said. “There you had a context where it was pregnant women and their soon-to-be babies that bore the brunt of the global concern. We would not be worrying that much about Zika as a threat, but it was precisely because of congenital Zika syndrome that we became globally aware.”

If pregnant women are sometimes uniquely susceptible to contracting infectious diseases, and can suffer distinctive consequences with some illnesses, why the historical hesitancy to vaccinate them?

“There are many factors contributing to this near categorical exclusion, including overinflated perceptions of risk in pregnancy as well as liability concerns,” Dr. Krubiner explained. “This is despite the fact there is no evidence of harm associated with the vast majority vaccines given to pregnant women, even among the category of replication-competent vaccines that give rise to the greatest concerns.”

The PREVENT team acknowledged that changing the status quo will be an uphill battle, but the risk of not doing so could have far more catastrophic consequences.

“Paradigm shifts are rarely easy,” Dr. Krubiner told Contagion®. “Adopting these recommendations will require significant changes in how people think about pregnant women in the context of research and in the delivery of medical interventions. It will also require institutions to adopt new processes and, in some cases, make additional investments. But changing from business as usual is critically important, both as a matter of social justice and to have successful public health responses to outbreaks.”

Certain “low-hanging fruit” action items are a good place to start, according to Dr. Faden, such as collecting better data both by surveillance systems for infectious disease and general national health statistics.

“To break this vicious cycle, we need to be going back to the pipeline and saying there is a real responsibility on those who determine, whether by funding or scientific proclivity, what vaccines are in the pipeline for emerging or re-emerging pathogens,” she concluded.