BackgroundSome patients with chronic hepatitis C virus (HCV) infection forego treatment due to concerns about treatment efficacy, treatment duration, and side effects.ObjectiveThe purpose of this study was to quantify patient preferences among possible outcomes associated with new, direct-acting antiviral agents (DAAs) for the treatment of HCV infection and determine which treatment features are most important to patients in making treatment decisions.MethodsAdult participants with a self-reported physician diagnosis of HCV infection in five countries completed a web-enabled, choice-format conjoint analysis survey. The survey presented participants with 20 treatment-choice questions. Each treatment-choice question included a pair of hypothetical treatment profiles with varying levels of six attributes: treatment duration; chance of getting rid of the virus completely (i.e. likelihood of a sustained virologic response [SVR]); weeks on an additional, third medicine (i.e. a DAA); risk of a severe rash; risk of severe anemia; and number of times a day the third medicine is taken. Treatment-choice questions were based on a predetermined experimental design with known statistical properties. Random-parameters logit was used to estimate preference weights for all attribute levels and the mean relative importance of each attribute.Results284 participants completed the survey. Likelihood of an SVR was the most important outcome to participants, followed by severe anemia risk, severe rash risk, therapy type (a combination of total weeks of treatment and weeks on the third medicine), and dosing of the third medicine. Controlling for other factors, preferences were similar across all therapy types examined.ConclusionPatients with HCV infection indicate a willingness to accept an increased risk of side effects for sufficient improvement in the likelihood of treatment response.Electronic Supplementary MaterialSupplementary material is available for this article at 10.1007/BF03262498 and is accessible for authorized users.