Randomized Trials of Retosiban Versus Placebo or Atosiban in Spontaneous Preterm Labor

Abstract

Despite considerable efforts to conduct two adequate and well-controlled studies in patients with sPTL, both studies were unable to recruit effectively and consequently terminated prematurely. Key factors negatively affecting participation were patient and physician resistance to use of a placebo comparator, lack of investigator consensus on diagnostic criteria and acceptance of protocol procedures, and ethics committee decisions. Meaningful cooperation between pharmaceutical companies, regulatory authorities, and the obstetric community is essential for future development of drugs to treat sPTL.