Trials of interventions for ovarian and testicular germ cell tumors registered in ClinicalTrials.gov: A cross-sectional study

Introduction: There is unmet need in the treatment of ovarian and testicular germ cell tumors (GCTs). This study analyzed registered trials of interventions for GCTs. Materials and methods: We included trials of interventions for GCTs registered on ClinicalTrials.gov by July 29, 2022. We analyzed their interventions, outcome measures and study design. Results: We included 142 trials registrations; 42 (30 %) for ovarian GCTs, 50 (35 %) for testicular GCTs, and 50 (35 %) trials for both. The majority of the trials were completed (56 %) and did not have results available (75 %). Most trials were in Phase 2. Information about the study design were not reported for many analyzed trials. Most trials had a single-group assignment (44 %) and were open-label (68 %). The median planned number of enrolled participants was 43. Most registrations used medicine(s) (87 %), either as a single type of intervention or in combination. The most commonly used type of medicine was chemotherapy (54 %). Primary outcome was not reported in 23 % of registrations, and secondary outcomes were not reported in 35 % of registrations. Overall survival was used in 6 % of registrations as a primary outcome and in 31 % of registrations as a secondary outcome. Conclusions: Few trials on GCTs were registered on ClinicalTrials.gov, and their number was declining in recent times. Most registrations did not report relevant information about the study design, or results if completed. More effort is needed to foster trials on GCTs, as well as to optimize the management of the registrations and foster the publication of research results.