Applying a diffusion of innovations framework to the scale-up of direct-acting antiviral therapies for hepatitis C virus infection: Identified challenges for widespread implementation

Background and Aims: Interferon-free, direct-acting antivirals (DAAs) for hepatitis C virus (HCV) offer much promise to achieve World Health Organization targets by 2030. However, impediments at the practitioner and health-system level will continue to obstruct the scale-up of DAAs worldwide unless identified and acted upon. Applying a diffusion of innovations framework, the aim of this study was to identify structural factors impacting practitioner experiences of managing HCV treatment. Methods: In-depth, semi-structured, telephone interviews took place between September 2018 and April 2019 to investigate barriers and facilitators for engaging in HCV management and DAA therapy amongst general practitioners (GPs) who prescribe opioid agonist therapy and drug and alcohol specialists in Australia. Interviews were transcribed verbatim, de-identified, and coded, and data were analysed with iterative categorisation and thematic analysis using Everett Rogers's diffusion of innovation framework. Results: amongst 30 participants (12 GPs, 18 drug and alcohol specialists), several structural factors were reported to impede practitioner efforts to deliver optimal HCV care. Two primary themes were explored: contextual factors for the diffusion of DAA therapies, including attempts by participants to shift clinic culture and respond to siloed health structures, and adopter factors. Some participants chose to 'rock the boat' by circumventing clinic protocol and HCV guidelines to treat more clients, effectively shifting adopter categories to become greater advocates in HCV care. Also, while a role for GPs as the 'new adopters' in HCV management was discussed, many participants expressed uncertainty as to how much GPs should become involved in the diffusion of DAA therapies more widely. Conclusions: Reducing the global burden of HCV infection will not be possible without the widespread delivery of HCV treatment amongst practitioners. Practitioners and health workers require leadership and resources from health authorities so that the individual and population-level benefits of DAA therapy are realised.