There has been some controversy concerning the curative potential of new treatments for hepatitis C. This follows a systematic review of the Cochrane Collaboration questioning the clinical benefits of direct-acting antivirals (DAAs). This controversy has been debated as a matter of methods regarding how best to evidence treatment in an evidence-based medicine (EBM) approach. Drawing from science and technology studies (STS), we offer an alternative perspective. We propose a different way of thinking with evidence; one which treats 'evidencing as performative'. Using the Cochrane review and its linked published responses as a resource for this analysis, we consider how hepatitis C cure is differently made-up through the knowledge-making practices performing it. We show how matters of apparent fact in evidence-based science are enacted as matters of clinical, social and ethico-political concern. We notice hepatitis C cure as a fluid object in negotiation. We highlight the limits of current debate to advocate a more critical and careful practice-based approach to knowing hepatitis C cure. This calls upon public health researchers to reflect on the performative work of their evidencing. We propose a 'more-than' EBM approach which treats 'evidence-based' science as an 'evidence-making intervention'. We consider the implications of such an approach for the evidencing of public health interventions and for treating hepatitis C in the DAA era of 'viral elimination'.