Zika and the Regulatory Regime for Licensing
Vaccines for Use During Pregnancy
Microcephaly and other severe fetal brain defects (congenital Zika
syndrome) caused by the Zika virus have prompted an urgent effort to
develop and license a safe and efficacious vaccine.
1 Yet, that effort has run
up against one of the most formidable barriers in vaccine research: pregnant
women are almost always excluded from clinical trials for fear that the
intervention may harm the fetus.
2 This article analyzes the existing
regulatory framework for vaccines intended for use during pregnancy in an
effort to identify ways the process may be reconsidered in light of recent
public health emergencies that had a disproportionate effect on pregnant
Despite those recent public health emergencies and the routine
administration of immunizations like diphtheria, pertussis, and tetanus to
pregnant women, there is no vaccine licensed for use during pregnancy in the
3 The regulatory review normally required by the U.S. Food
and Drug Administration (“FDA”) for new drugs and biologic products
(including vaccines) demands substantial evidence as to safety, purity, and
potency both generally and for subpopulations designated on a product’s
label. However, vaccines routinely administered during pregnancy are
permitted through an alternative post hoc system that does not rely on the
gold standard of double-blind, placebo controlled trials.
4 Under that
alternative, the FDA defers to the U.S. Centers for Disease Control and
*Fulbright Canada Research Chair in Health Law, Policy, and Ethics, University of Ottawa,
Associate Professor, University of Missouri School of Law and Scholar, O’Neill Institute for
National and Global Health Law, Georgetown University. JD Harvard, MPhil, Oxford, B.S.,
Kansas State University.
1. Erika Check Hayden, The Race is on to Develop Zika Vaccine, NATURE (March
2. Mary C. Blehar et al., Enrolling Pregnant Women: Issues in Clinical Research, 23
WOMEN’S HEALTH ISSUES e39, e40 (2013).
3. Getta K. Swamy & R. Phillips Heine, Vaccinations for Pregnant Women, OBSTETRICS
4. Jeffery N. Roberts & Marion F. Gruber, Regulatory Considerations in the Clinical
Development of Vaccines Indicated for Use During Pregnancy, 33 VACCINE 966, 967 (2015).