Safety and Efficacy of SOF/VEL/VOX FDC for 12 Weeks and SOF/VEL for 12 Weeks in DAA-Experienced Adults With Chronic HCV Infection Who Have Not Received an NS5A Inhibitor

Study Overview
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Brief Summary
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The primary objectives of the study are to evaluate the efficacy, safety, and tolerability of treatment with sofosbuvir/velpatasvir/voxilaprevir (Vosevi®; SOF/VEL/VOX) fixed-dose combination (FDC) for 12 weeks and of sofosbuvir/velpatasvir (Epclusa®; SOF/VEL) FDC for 12 weeks in direct-acting antiviral (DAA)-experienced adults with chronic hepatitis C virus (HCV) infection with or without cirrhosis who have not received prior treatment with a regimen containing an inhibitor of the HCV NS5A protein.

Official Title
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A Phase 3, Global, Multicenter, Randomized, Open-Label Study to Investigate the Safety and Efficacy of Sofosbuvir/Velpatasvir/GS-9857 Fixed-Dose Combination for 12 Weeks and Sofosbuvir/Velpatasvir for 12 Weeks in Direct-Acting Antiviral-Experienced Subjects With Chronic HCV Infection Who Have Not Received an NS5A Inhibitor

Conditions
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Hepatitis C Virus Infection

Intervention / Treatment
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* Drug: SOF/VEL/VOX
* Drug: SOF/VEL


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Willing and able to provide written informed consent HCV RNA ≥ 10^4 IU/mL at screening Chronic HCV infection (≥ 6 months) Treatment experienced with a direct acting antiviral medication not including a NS5A Inhibitor for HCV Use of protocol specified methods of contraception Key Exclusion Criteria: Current or prior history of clinically significant illness that may interfere with participation in the study Screening ECG with clinically significant abnormalities Laboratory results outside of acceptable ranges at screening Pregnant or nursing female Chronic liver disease not caused by HCV Infection with hepatitis B virus (HBV) or human immunodeficiency virus (HIV) Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SOF/VEL/VOX<br>SOF/VEL/VOX for 12 weeks | Drug: SOF/VEL/VOX<br>* 400/100/100 mg FDC tablet administered orally once daily with food<br>* Other names: GS-7977/GS-5816/GS-9857;|
| Experimental: SOF/VEL<br>SOF/VEL for 12 weeks | Drug: SOF/VEL<br>* 400/100 mg FDC tablet administered orally once daily without regard to food<br>* Other names: GS-7977/GS-5816;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With Sustained Virologic Response (SVR) 12 Weeks After Discontinuation of Therapy (SVR12) | SVR12 was defined as HCV RNA < the lower limit of quantitation (LLOQ) at 12 weeks after stopping study treatment. | Posttreatment Week 12 | 
| Percentage of Participants Who Permanently Discontinue Study Drug Due to an Adverse Event |  | Up to 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With SVR at 4 and 24 Weeks After Discontinuation of Therapy (SVR4 and SVR24) | SVR4 and SVR24 were defined as HCV RNA < LLOQ at 4 and 24 weeks after stopping study treatment, respectively. | Posttreatment Weeks 4 and 24 | 
| Percentage of Participants With HCV RNA < LLOQ On Treatment |  | Weeks 1, 2, 4, 8 and 12 | 
| Change From Baseline in HCV RNA |  | Weeks 1, 2, 4, 8, and 12 | 
| Percentage of Participants With Virologic Failure | On-treatment virologic failure: Breakthrough (confirmed HCV RNA ≥ LLOQ after having previously had HCV RNA < LLOQ while on treatment), or Rebound (confirmed > 1 log10 IU/mL increase in HCV RNA from nadir while on treatment), or Non-response (HCV RNA persistently ≥ LLOQ through 8 weeks of treatment) Virologic relapse: Confirmed HCV RNA ≥ LLOQ during the posttreatment period having achieved HCV RNA < LLOQ at last on-treatment visit. | Up to Posttreatment Week 24 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Chronic