Twinrix Pregnancy Registry

The purpose of the Twinrix Pregnancy Registry is to prospectively collect data describing exposure to Twinrix before or during pregnancy, potential confounding factors (such as exposure to other medications) and information related to the outcome of the pregnancy. This is a prospective, voluntary, observational, exposure-registration study. Twinrix is designated as Food and Drug Administration (FDA) Pregnancy Category C, which means that its safety in human pregnancy has not been determined. The Registry is intended to provide an early signal of potential risks in advance of results from formal epidemiologic studies. Registry statistics can supplement animal reproductive toxicology studies and assist clinicians in evaluating the potential risks and benefits of vaccination for individual patients.

The Twinrix Pregnancy Registry will be maintained by GSK Vaccines Clinical Safety and Pharmacovigilance. Enrolment in the Registry will begin at the time of commercial launch of Twinrix in the United States (US). At the time of initiation of the Registry, pre-existing reports of pregnancy from clinical trials will be evaluated and enrolled when the criteria for registration are met. Reporting of exposed pregnancies is voluntary. Pregnancies will be registered following maternal exposure to Twinrix within 28 days prior to conception or during pregnancy. Registration of pregnancies is prospective, i.e., reported during pregnancy before the pregnancy outcome is known. Retrospective reports, in which the pregnancy outcomes are known at the time of reporting, will also be reviewed to assist in the detection of any unusual patterns that may exist among the reported birth defects. However, because there is no denominator from which risk can be calculated, these reports will be excluded from the analysis.