BackgroundMetreleptin, a recombinant analog of human leptin, is an approved therapy, adjunct to diet, to treat the metabolic complications of leptin deficiency in patients with lipodystrophy – a group of rare diseases characterized by a paucity of adipose tissue. MEASuRE (Metreleptin Effectiveness And Safety Registry) is a post-authorization, voluntary registry that gathers long-term safety and effectiveness data on metreleptin. Here, we present the aims and evolution of MEASuRE.MethodsMEASuRE was established to collect data from patients receiving commercially supplied metreleptin in the United States (US) and European Union (EU). MEASuRE aims to determine the incidence and severity of safety events and describe the clinical characteristics and therapeutic outcomes in the metreleptin-treated population. A key feature of MEASuRE is that it accumulates data from different sources to meet post-authorization objectives. US data are received directly from treating physicians via a contract research organization-mediated electronic data capture system. In the EU, data are received via the European Registry of Lipodystrophies managed by the European Consortium of Lipodystrophies (ECLip), a platform established by researchers and physicians to advance the knowledge of lipodystrophy. MEASuRE complies with applicable regulatory requirements governing privacy, and the storage, management, and access of data.ResultsLeveraging processes, infrastructure, and data from the ECLip registry presented several challenges that were addressed during MEASuRE’s development, including the expansion of the ECLip registry to accommodate MEASuRE-specific data elements, extensive data matching processes to ensure data consistency regardless of source, and rigorous data validation following the amalgamation of global data. Through the support of ECLip, MEASuRE is now a fully operational registry with the capacity for gathering and integrating standardized US- and EU-derived data. As of 31st October 2022, 15 US and four EU sites have participated in the MEASuRE, enrolling 85 patients globally.ConclusionsOur experiences show that a post-authorization product registry can be successfully integrated into an existing patient registry. We propose that, through collaboration with existing registries and use of their established resources, patient enrolment timelines and data collection for new registries can be expedited. The learnings presented here may be applicable to other registries with similar objectives.Trial registrationNCT02325674; Registered 25 December 2014 - Retrospectively registered’.https://clinicaltrials.gov/ct2/show/NCT02325674.