Challenges in translating end points from trials to observational cohort studies in oncology

• Type of Material: Article
• Authors: Anne Gulbech Ording, Aarhus University; Deirdre Cronin-Fenton, Aarhus University; Vera Ehrenstein, Aarhus University; Timothy Lash, Emory University; John Acquavella, Aarhus University; Mikael Rørth, Aarhus University; Henrik Toft Sørensen, Aarhus University
• Language: English
• Date: 2016
• Publisher: Dove Medical Press
• Publication Version: Final Published Version
• Copyright Statement: © 2016 Ording et al. This work is published and licensed by Dove Medical Press Limited.
• License: Creative Commons Attribution-Noncommercial 3.0 Unported
• Final Published Version (URL): http://dx.doi.org/10.2147/CLEP.S97874
• Title of Journal or Parent Work: Clinical Epidemiology
• ISSN: 1179-1349
• Start Page: 195
• End Page: 195
• Grant/Funding Information: This work was supported by the Program for Clinical Research Infrastructure established by the Lundbeck Foundation and the Novo Nordisk Foundation.
• Keywords: research design; neoplasms; endpoint determination; treatment outcome; medical oncology
• Research Categories: Health Sciences, Oncology; Health Sciences, Epidemiology

Abstract

Clinical trials are considered the gold standard for examining drug efficacy and for approval of new drugs. Medical databases and population surveillance registries are valuable resources for post-approval observational research, which are increasingly used in studies of benefits and risk of new cancer drugs. Here, we address the challenges in translating endpoints from oncology trials to observational studies. Registry-based cohort studies can investigate real-world safety issues – including previously unrecognized concerns – by examining rare endpoints or multiple endpoints at once. In contrast to clinical trials, observational cohort studies typically do not exclude real-world patients from clinical practice, such as old and frail patients with comorbidity. The observational cohort study complements the clinical trial by examining the effectiveness of interventions applied in clinical practice and by providing evidence on long-term clinical outcomes, which are often not feasible to study in a clinical trial. Various endpoints can be included in clinical trials, such as hard endpoints, soft endpoints, surrogate endpoints, and patient-reported endpoints. Each endpoint has it strengths and limitations for use in research studies. Endpoints used in oncology trials are often not applicable in observational cohort studies which are limited by the setting of standard clinical practice and by non-standardized endpoint determination. Observational studies can be more helpful moving research forward if they restrict focus to appropriate and valid endpoints.