Pregnancies in subjects on oncology clinical trials: Analysis from the Cancer Therapy Evaluation Program (CTEP) database.

Abstract

e18239 Background: The NCI Cancer Therapy Evaluation Program (CTEP) has developed guidance and reporting measures to balance inclusion of younger cancer patients on trials with minimizing potential risks. CTEP began mandating the use of 2 forms of contraception for all participants of child bearing potential starting in the early 2000s in trials of thalidomide in multiple myeloma. The development of oncology clinical trials using other known teratogens such as Hedgehog Inhibitors led to development of comprehensive guidance on enrolling women on clinical trials. In 2012, CTEP further updated its guidelines to develop a reporting system for pregnancies occurring on clinical trial. Methods: We performed a retrospective analysis of the CTEP Adverse Event Reporting System (AERS) to identify unanticipated pregnancies in subjects or their partners while on oncology clinical trials. Results: 33 events were identified between 2011 and 2018, including 21 female and 11 male. One female subject got pregnant twice on the same trial. In female subjects, there were 4 live births, 1 active pregnancy, 5 spontaneous abortions, 5 medical termination of pregnancy and 1 death of the mother due to cancer. Outcome of pregnancy was not reported for 6 female subjects. Of the live births: 3 received an immunotherapy checkpoint inhibitor, and 1 received trastuzumab. Of 5 spontaneous abortions: 3 received cytotoxic chemotherapy, one radiation and one trastuzumab. Of 12 male subjects whose partners got pregnant: 3 live births, 2 active pregnancy, no pregnancy loss. Outcome of pregnancy was not reported for 6 male subjects. Conclusions: Though uncommon, pregnancies on clinical trial still occur despite requiring subjects to use 2 effective forms of contraception. With the increasing number of younger subjects being included in clinical trials for cancer, information about pregnancy outcomes in patients being treated with experimental agents is scientifically valuable and important to collect from study subjects and their partners. Since not all anti-cancer agents are of equal teratogenic potential, it is vital that this data continues to be collected and reported, including long term follow up of the pregnancy and the health of the child.