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Sofosbuvir-velpatasvir single-tablet regimen administered for 12 weeks in a phase 3 study with minimal monitoring in India

Background and aims

In clinical studies, sofosbuvir–velpatasvir has demonstrated high cure rates and favorable tolerability in patients chronically infected with chronic hepatitis C virus (HCV) of any genotype. We evaluated the effectiveness and safety of sofosbuvir–velpatasvir administered with minimal medical monitoring to patients in India.

Methods

At 16 sites in India, 129 adult patients with chronic HCV infection of any genotype initiated 12 weeks of once-daily sofosbuvir–velpatasvir (400–100 mg). Patients with compensated cirrhosis or prior treatment experience could be included in the study. Study drug was dispensed monthly, but there were no on-treatment study assessments. The primary efficacy endpoint was rate of sustained virologic response (HCV RNA < 15 IU/mL) 12 weeks after treatment (SVR12), which was compared to a pre-specified performance goal of 85%.

Results

The majority of patients had HCV genotype 3 infection (70%), followed by HCV genotype 1 (22%). The SVR12 rate was 93% (120/129; 95% CI, 87% to 97%) (p = 0.009 compared with the 85% performance goal). Of the nine patients who did not achieve SVR12, 1 experienced virologic failure, 2 relapsed after treatment, 1 withdrew consent after treatment, and 5 were lost to follow-up (1 during and 4 after treatment). Sofosbuvir–velpatasvir was well-tolerated, and no patients discontinued treatment because of an adverse event. The most frequently reported adverse events were headache (3% of patients), upper abdominal pain (2%), and pyrexia (2%).

Conclusions

In this study conducted at multiple sites in India, sofosbuvir–velpatasvir administered without genotype restriction or on-treatment safety assessments was well-tolerated and highly effective.

Sofosbuvir and Velpatasvir for HCV Genotype 1, 2, 4, 5, and 6 Infection

BACKGROUND

A simple treatment regimen that is effective in a broad range of patients who are chronically infected with the hepatitis C virus (HCV) remains an unmet medical need.

METHODS

We conducted a phase 3, double-blind, placebo-controlled study involving untreated and previously treated patients with chronic HCV genotype 1, 2, 4, 5, or 6 infection, including those with compensated cirrhosis. Patients with HCV genotype 1, 2, 4, or 6 were randomly assigned in a 5:1 ratio to receive the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor velpatasvir in a once-daily, fixed-dose combination tablet or matching placebo for 12 weeks. Because of the low prevalence of genotype 5 in the study regions, patients with genotype 5 did not undergo randomization but were assigned to the sofosbuvir-velpatasvir group. The primary end point was a sustained virologic response at 12 weeks after the end of therapy.

RESULTS

Of the 624 patients who received treatment with sofosbuvir-velpatasvir, 34% had HCV genotype 1a, 19% genotype 1b, 17% genotype 2, 19% genotype 4, 6% genotype 5, and 7% genotype 6. A total of 8% of patients were black, 19% had cirrhosis, and 32% had been previously treated for HCV. The rate of sustained virologic response among patients receiving sofosbuvir-velpatasvir was 99% (95% confidence interval, 98 to >99). Two patients receiving sofosbuvir-velpatasvir, both with HCV genotype 1, had a virologic relapse. None of the 116 patients receiving placebo had a sustained virologic response. Serious adverse events were reported in 15 patients (2%) in the sofosbuvir-velpatasvir group and none in the placebo group.

CONCLUSIONS

Once-daily sofosbuvir-velpatasvir for 12 weeks provided high rates of sustained virologic response among both previously treated and untreated patients infected with HCV genotype 1, 2, 4, 5, or 6, including those with compensated cirrhosis. (Funded by Gilead Sciences; ClinicalTrials.gov number, NCT02201940.).