Letter: new treatments for hepatitis C have implications for quality of life in people who inject drug--authors' reply.

Abstract

We appreciate the input from Higgs et al.1 about the importance of studying the people who inject drugs (PWID) in the context of comprehensive benefits of treatment with direct-acting anti-virals (DAA)-based regimens for HCV.2 We have to note that this population, although very important, have been excluded in most phase 3 clinical trials. Nevertheless, Higgs and colleagues do raise a very important point. Indeed, hepatitis C population is complex and includes multiple subpopulations with a greatly varying socio-demographic portrait. It is reasonable to believe that in some of these subpopulations, health-related quality of life (HRQL) issues may be not the same as in others and neither would be the impact of curing their HCV infection.3, 4 In this context, the PWID population with HCV may be one of those subpopulations with a substantially distinct HRQL presentation due to multiple reasons ranging from physical and mental health-related issues to issues related to social stigma. Although patient-reported outcomes data for this specific HCV population are currently lacking, we have shown the benefits of receiving interferon-free and ribavirin-free regimens (improvement in fatigue and quality of life during treatment and after achieving SVR) in a number of HCV subpopulations with other risk factors. Furthermore, the improvement can also be shown for HCV patients who reported having a history of injected drug use in the past. Therefore, we can hope and suspect that this benefit may be reproducible in the PWID population. Given the difficulty of treating the specific PWID subpopulation with HCV as highlighted by Higgs and colleagues, we would like to emphasise again the utmost importance of systematic collection of HRQL and other patient-reported outcomes data during and after treatment in all clinical trials which would involve PWID patients with HCV. This will be critical for both a comprehensive assessment of the effectiveness of the new anti-HCV treatment regimens, as well as for the future calculations of any cost–benefit-related metrics that would include expanding access to DAA-based regimens in this patient population. The authors' declarations of personal and financial interests are unchanged from those in the original article.2