Background: The diversity of patient experiences of orphan drug development has until recently been overlooked, with the existing literature reporting the experience of some patients and not others. The current evidence base (the best available current research) is dominated by quantitative surveys and patient reported outcome measures defined by researchers. Where research that uses qualitative methods of data collection and analysis has been conducted, patient experiences have been studied using content analysis and automatic textual analysis, rather than in-depth qualitative analytical methods. Systematic reviews of patient engagement in orphan drug development have also excluded qualitative studies. The aim of this paper is to review qualitative literature about how patients and other members of the public engage with orphan drug development.

Methods: We conducted a systematic search of qualitative papers describing a range of patient engagement practices and experiences were identified and screened. Included papers were appraised using a validated tool (CASP), supplemented by reporting guidance (COREQ), by two independent researchers.

Results: 262 papers were identified. Thirteen papers reported a range of methods of qualitative data collection. Many conflated patient and public involvement and engagement (PPIE) with qualitative research. Patients were typically recruited via their physician or patient organisations. We identified an absence of overarching philosophical or methodological frameworks, limited details of informed consent processes, and an absence of recognisable methods of data analysis. Our narrative synthesis suggests that patients and caregivers need to be involved in all aspects of trial design, including the selection of clinical endpoints that capture a wider range of outcomes, the identification of means to widen access to trial participation, the development of patient facing materials to optimise their decision making, and patients included in the dissemination of trial results.

Conclusions: This narrative qualitative synthesis identified the explicit need for methodological rigour in research with patients with rare diseases (e.g. appropriate and innovative use of qualitative methods or PPIE, rather than their conflation); strenuous efforts to capture the perspectives of under-served, under-researched or seldom listened to communities with experience of rare diseases (e.g. creative recruitment and wider adoption of post-colonial practices); and a re-alignment of the research agenda (e.g. the use of co-design to enable patients to set the agenda, rather than respond to what they are being offered).