Regulatory considerations in the clinical development of vaccines indicated for use during pregnancy

Despite supportive public health policies (e.g., ACIP recommendations), the potential for providing clinical benefit through maternal immunization has yet to be fully realized. For vaccines already licensed and approved for use in adults, specific FDA approval for use during pregnancy to prevent disease in the mother and/or infant may have a significant impact on uptake and usage in pregnant women. In addition, for either a licensed vaccine or a novel vaccine, FDA approval for use during pregnancy would result in labeling that would serve as a resource for practitioners and would facilitate the safe and effective use of the vaccine during pregnancy. In the U.S., while many vaccines are approved for use in adults and most are not contraindicated for use in pregnant women, no vaccine is licensed for use specifically during pregnancy. Among the perceived obstacles hindering the clinical development of vaccines for use in pregnancy, regulatory issues are frequently cited. One aim of this article is to address the perceived regulatory obstacles. General concepts and regulatory considerations for clinical safety and effectiveness evaluations for vaccines indicated for use during pregnancy will be discussed. This discussion is not intended to establish data requirements or to articulate agency policy or guidance regarding specific vaccine products.