About The Study

The E/C/F/TAF switch study is a 32-week pilot study designed to assess the benefit of switching antiretroviral therapy (ART) regimens to E/C/F/TAF prior to starting ledipasivir-sofosbuvir (LPV-SOF), direct acting antivirals (DAA) therapy, in HIV-HCV co-infected individuals. Specifically, the study will assess whether ART switching is feasible and, if switching will reduce drug-drug interactions between the HIV and HCV study drugs.

The trial will include 25 participants from two research sites in Ottawa (Ottawa Hospital Research Institute) and Montreal (McGill University Health Centre).

About The Disease

Approximately 30% of people living with HIV are co-infected with hepatitis C virus (HCV). Co-infected people have a much greater risk of developing serious health complications including liver disease or cirrhosis than people living with HCV alone. While ART has been shown to greatly reduce health complications associated with HIV, the therapy may contribute to liver disease in co-infected individuals.

The development of DAAs has greatly increased the viral cure rate for people with HCV with fewer side-effects than previous therapies. However, little is known about drug-drug interaction rates between many ART and DAA regimens for people with co-infections.

Study Approach

Participants will switch their ART regimen to E/C/F/TAF for one month prior to beginning ledipsivir-sofosbuvir for treatment of their HCV. This pre-study switch allows researchers to measure the tolerability of the study drug. After the initial month participants will complete a 12-week course of LPV-SOF, remaining on E/C/F/TAF, with the goal of HCV viral cure. Participants will remain on E/C/F/TAF for a further 12 weeks with follow-up occurring at that time.

Eligibility Requirements


  • 18 years old or older living with HIV and HCV
  • On antiretroviral therapy (ART)
  • No history of protocol specific resistant mutation
  • Genotype 1 infection
  • Stage 3 or 4 fibrosis
  • No evidence of liver decompensation
  • Willing to adhere to study protocol
  • Not pregnant or planning on becoming pregnant

Not Allowed

  • Use of drugs with documented interactions with study drugs
  • History of HIV-1 drug resistance mutations
  • Platelets <50×109 /L

Additional Information

If you would like more information on this clinical study, please refer to a participating site.

Principal Investigators

Here’s who is leading this study.

Can’t find what you’re looking for? Email ctninfo@hivnet.ubc.ca.

Dr. Curtis Cooper

Co-Leader, Co-infections and Related Conditions Core; Member, Steering Committee

University of Ottawa; The Ottawa Hospital

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Participating Sites

Here’s where this study is being conducted.