Randomized, Double-blind, Multicenter, Phase III Study Comparing the Efficacy and Safety of Retosiban Versus Atosiban Therapy for Women in Spontaneous Preterm Labor

The primary objective of this study is to demonstrate the superiority of retosiban to prolong pregnancy in females with spontaneous preterm labor compared with atosiban. This objective is based on the hypothesis that prolonging the time to delivery in the absence of harm may benefit the newborn, particularly in women who experience spontaneous preterm labor at early gestational ages (GA). This study is designed to test this hypothesis through a direct comparison with atosiban, a mixed oxytocin vasopressin antagonist indicated for short-term use to delay imminent preterm birth in women between 24^0/7 and 33^6/7 weeks' gestation in preterm labor. This is a randomized, double-blind, double-dummy study, which consists of 6 phases: Screening, Inpatient Randomized Treatment, Post Infusion Assessment, Delivery, Maternal Post Delivery Assessment, and Neonatal Medical Review. Approximately 330 females will be randomly assigned to retosiban or atosiban treatment in a 1:1 ratio. The duration of any one subject's (maternal or neonatal) participation in the study will be variable and dependent on GA at study entry and the date of delivery.

本研究的核心目标为证实：相较于阿托西班（atosiban），雷托西班（retosiban）可更有效地延长自发性早产女性的妊娠时长。该研究目标基于下述假说：在未造成伤害的前提下延长分娩间隔，可使新生儿获益，对于妊娠早期胎龄（gestational age, GA）发生自发性早产的女性而言，这一获益尤为显著。本研究通过与阿托西班直接对比来验证上述假说。阿托西班属于混合性催产素-血管加压素拮抗剂，获批用于妊娠24^0/7至33^6/7孕周的早产女性，短期使用以推迟即将发生的早产。本研究为随机、双盲、双模拟试验，共包含6个阶段：筛选期、住院随机治疗期、输注后评估期、分娩期、产妇产后评估期以及新生儿医学审查期。预计将有330名女性受试者以1:1的随机比例被分配至雷托西班组或阿托西班组接受治疗。任意一名受试者（产妇或新生儿）在本研究中的参与时长均存在差异，具体取决于研究入组时的胎龄以及分娩日期。