Background: Differences between trial participants and real-world users of medicines are often considered one of the main reasons for generating ‘real-world evidence’. However, few studies have systematically explored these potential differences and their impact on study results.
Objectives: This symposium will address the following issues: (i) Does current evidence suggest a systematic difference between trial participants and real-world users? (ii) To what extent are real-world users different from trial participants when considering patient characteristics and trial eligibility? (iii) How do differences between real-world users and trial participants affect estimates of treatment effectiveness and safety? (iv) How do differences in measurement of risk factors and outcomes affect perceived differences between trial evidence and real-world evidence? The symposium will target any pharmacoepidemiologist working within the ‘real-world evidence’ space.
Description: The symposium will be initiated by prof. Anton Pottegård. The common perception that the difference between trial participants and real-world users is a well-documented fact will be challenged, followed by selected examples of real-world efficacy estimates (compared to trial findings) to set the scene for the subsequent presentations.Prof. Olaf Klungel will review the extent of exclusion of elderly from pivotal trials on therapeutic indications typically present among elderly. Further, examples of the impact of differences in patient characteristics between trial participants and real-world users on effectiveness and safety of medicines (direct oral anticoagulants for atrial fibrillation and chemotherapy for non-small cell lung cancer) will be discussed. Daniel Morales, will review how exclusion rates vary by trial setting, funding source and over time. Examples demonstrating how differences between trial participants and real-world users impact how we quantify the safety and effectiveness of medicines (ACE inhibitors for renal disease and antiplatelets for stroke) will be discussed. Mehdi Najafzadeh, will review the difference in how outcomes and risk factors are captured in trials versus in databases. He will discuss how this impact on findings from different studies and propose potential solutions for addressing such differences in the future. The symposium will end with a panel discussion. Selected literature references will be prepared in advance for participants to easily access them.