Drug Interaction Report

Coadministration with the bivalent respiratory syncytial virus (RSV) vaccine may decrease the immune response to the pertussis component of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine, adsorbed (Tdap). When these vaccines were coadministered in healthy non-pregnant women, lower geometric mean antibody concentrations (GMCs) to the acellular pertussis antigens (pertussis toxin, filamentous hemagglutinin, and pertactin) were measured compared to separate administration and did not meet non-inferiority criteria. Immune responses to the RSV vaccine antigens and the remaining Tdap antigens were non-inferior to those after separate administration. However, no safety concerns were identified, and the clinical relevance is unknown. The U.S. Centers for Disease Control and Prevention (CDC) advises that the bivalent RSV vaccine may be given in combination with Tdap in either pregnant women or other adults. Current local immunization guidelines should also be consulted for recommended immunization schedules. Additional parameters related to administration of vaccines in general should also be considered, including but not limited to, adverse effects (e.g., fever, headache, pain at injection site), indication, risk of developing vaccine-preventable disease, and vaccine reactogenicity profiles.