Sofosbuvir (SOVALDI(®)), a potent, once-daily, orally administered nucleotide analog prodrug inhibitor of the hepatitis C virus (HCV) NS5B polymerase is approved in the USA, EU, Canada, and other ...regions for the treatment of HCV infection as a component of an antiviral treatment regimen. Sofosbuvir undergoes intracellular activation to form GS-461203 (active triphosphate, not detected in plasma), and ultimately the inactive, renally eliminated metabolite GS-331007. GS-331007 was identified as the primary analyte of interest for clinical pharmacology studies as it accounted for >90 % of systemic drug-related material exposure, and provided comparable exposure-response relationships for viral kinetics as observed for sofosbuvir. GS-331007 and sofosbuvir exhibit linear pharmacokinetics with minimal accumulation upon multiple dosing. Compared to healthy subjects, HCV-infected patients had modestly lower (39 %) GS-331007 area under the plasma concentration-time curve (AUC) and higher sofosbuvir AUC (60 %). Sofosbuvir can be administered without dose modification in HCV-infected patients with any degree of hepatic impairment or mild to moderate renal impairment. Sofosbuvir has a low propensity for clinically significant drug interactions with common concomitant medications used by HCV-infected patients. Clinically significant alterations in GS-331007 or sofosbuvir exposures are limited to potent inducers of intestinal P-glycoprotein that may lower exposure. In HCV-infected patients, demographic variables do not significantly influence GS-331007 and sofosbuvir exposures and no consistent exposure-response relationships were observed for efficacy or safety. This review focuses on the clinical pharmacokinetics, pharmacodynamics, and pharmacokinetic-pharmacodynamic relationships of sofosbuvir, and summarizes a number of drug interaction studies with important concomitant medications commonly used by HCV-infected patients.
In clinical trials, treatment with a combination of the nucleotide polymerase inhibitor sofosbuvir and the antiviral drug ribavirin was associated with high response rates among patients with ...hepatitis C virus (HCV) genotype 2 infection, with lower response rates among patients with HCV genotype 3 infection.
We conducted a study involving patients with HCV genotype 2 or 3 infection, some of whom had undergone previous treatment with an interferon-based regimen. We randomly assigned 91 patients with HCV genotype 2 infection and 328 with HCV genotype 3 infection, in a 4:1 ratio, to receive sofosbuvir-ribavirin or placebo for 12 weeks. On the basis of emerging data from phase 3 trials indicating that patients with HCV genotype 3 infection had higher response rates when they were treated for 16 weeks, as compared with 12 weeks, the study was unblinded, treatment for all patients with genotype 3 infection was extended to 24 weeks, the placebo group was terminated, and the goals of the study were redefined to be descriptive and not include hypothesis testing. The primary end point was a sustained virologic response at 12 weeks after the end of therapy.
Of the 419 patients who were enrolled and treated, 21% had cirrhosis and 58% had received previous interferon-based treatment. The criterion for a sustained virologic response was met in 68 of 73 patients (93%; 95% confidence interval CI, 85 to 98) with HCV genotype 2 infection who were treated for 12 weeks and in 213 of 250 patients (85%; 95% CI, 80 to 89) with HCV genotype 3 infection who were treated for 24 weeks. Among patients with HCV genotype 3 infection, response rates were 91% and 68% among those without and those with cirrhosis, respectively. The most common adverse events were headache, fatigue, and pruritus.
Therapy with sofosbuvir-ribavirin for 12 weeks in patients with HCV genotype 2 infection and for 24 weeks in patients with HCV genotype 3 infection resulted in high rates of sustained virologic response. (Funded by Gilead Sciences; VALENCE ClinicalTrials.gov number, NCT01682720.).
In phase 2 trials, the nucleotide polymerase inhibitor sofosbuvir was effective in previously untreated patients with chronic hepatitis C virus (HCV) genotype 1, 2, or 3 infection.
We conducted two ...phase 3 studies in previously untreated patients with HCV infection. In a single-group, open-label study, we administered a 12-week regimen of sofosbuvir plus peginterferon alfa-2a and ribavirin in 327 patients with HCV genotype 1, 4, 5, or 6 (of whom 98% had genotype 1 or 4). In a noninferiority trial, 499 patients with HCV genotype 2 or 3 infection were randomly assigned to receive sofosbuvir plus ribavirin for 12 weeks or peginterferon alfa-2a plus ribavirin for 24 weeks. In the two studies, the primary end point was a sustained virologic response at 12 weeks after the end of therapy.
In the single-group study, a sustained virologic response was reported in 90% of patients (95% confidence interval, 87 to 93). In the noninferiority trial, a sustained response was reported in 67% of patients in both the sofosbuvir-ribavirin group and the peginterferon-ribavirin group. Response rates in the sofosbuvir-ribavirin group were lower among patients with genotype 3 infection than among those with genotype 2 infection (56% vs. 97%). Adverse events (including fatigue, headache, nausea, and neutropenia) were less common with sofosbuvir than with peginterferon.
In a single-group study of sofosbuvir combined with peginterferon-ribavirin, patients with predominantly genotype 1 or 4 HCV infection had a rate of sustained virologic response of 90% at 12 weeks. In a noninferiority trial, patients with genotype 2 or 3 infection who received either sofosbuvir or peginterferon with ribavirin had nearly identical rates of response (67%). Adverse events were less frequent with sofosbuvir than with peginterferon. (Funded by Gilead Sciences; FISSION and NEUTRINO ClinicalTrials.gov numbers, NCT01497366 and NCT01641640, respectively.).
Summary Background Interferon-based treatment is not suitable for many patients with hepatitis C virus (HCV) infection because of contraindications such as psychiatric illness, and a high burden of ...adverse events. We assessed the efficacy and safety of an interferon-free regimen—a fixed-dose combination of the nucleotide polymerase inhibitor sofosbuvir (400 mg) and the HCV NS5A inhibitor ledipasvir (90 mg), with and without ribavirin—in patients with genotype-1 hepatitis C infection who were treatment-naive or previously treated with a protease-inhibitor regimen. Methods For this open-label study, we enrolled 100 adult patients (>18 years) with HCV infection at a centre in the USA between Nov 2, 2012, and Dec 21, 2012. In cohort A, we used a computer-generated sequence to randomly assign (1:1:1; stratified by HCV genotype 1a vs 1b) 60 non-cirrhotic, treatment-naive patients to receive sofosbuvir plus ledipasvir for 8 weeks (group 1), sofosbuvir plus ledipasvir and ribavirin for 8 weeks (group 2), or sofosbuvir plus ledipasvir for 12 weeks (group 3). In cohort B, we randomly allocated (1:1; stratified by genotype and presence or absence of cirrhosis) 40 patients who previously had virological failure after receiving a protease inhibitor regimen to receive sofosbuvir plus ledipasvir for 12 weeks (group 4) or sofosbuvir plus ledipasvir and ribavirin for 12 weeks (group 5). 22 (55%) of 40 patients in cohort B had compensated cirrhosis. The primary endpoint was sustained virological response 12 weeks after treatment (SVR12), analysed by intention to treat. This study is registered with ClinicalTrials.gov , number NCT01726517. Findings In cohort A, SVR12 was achieved by 19 (95%) of 20 patients (95% CI 75–100) in group 1, by 21 (100%) of 21 patients (84–100) in group 2, and by 18 (95%) of 19 patients (74–100) in group 3. In cohort B, SVR12 was achieved by 18 (95%) of 19 patients (74–100) in group 4 and by all 21 (100%) of 21 patients (84–100) in group 5. Two patients had viral relapse; one patient was lost to follow-up after achieving sustained virological response 8 weeks after treatment. The most common adverse events were nausea, anaemia, upper respiratory tract infection, and headache. One patient in group five had a serious adverse event of anaemia, thought to be related to ribavirin treatment. Interpretation These findings suggest that the fixed-dose combination of sofosbuvir-ledipasvir alone or with ribavirin has the potential to cure most patients with genotype-1 HCV, irrespective of treatment history or the presence of compensated cirrhosis. Further clinical trials are needed to establish the best treatment duration and to further assess the contribution of ribavirin. Funding Gilead Sciences.
Patients chronically infected with hepatitis C virus (HCV) genotype 2 or 3 for whom treatment with peginterferon is not an option, or who have not had a response to prior interferon treatment, ...currently have no approved treatment options. In phase 2 trials, regimens including the oral nucleotide polymerase inhibitor sofosbuvir have shown efficacy in patients with HCV genotype 2 or 3 infection.
We conducted two randomized, phase 3 studies involving patients with chronic HCV genotype 2 or 3 infection. In one trial, patients for whom treatment with peginterferon was not an option received oral sofosbuvir and ribavirin (207 patients) or matching placebo (71) for 12 weeks. In a second trial, patients who had not had a response to prior interferon therapy received sofosbuvir and ribavirin for 12 weeks (103 patients) or 16 weeks (98). The primary end point was a sustained virologic response at 12 weeks after therapy.
Among patients for whom treatment with peginterferon was not an option, the rate of a sustained virologic response was 78% (95% confidence interval CI, 72 to 83) with sofosbuvir and ribavirin, as compared with 0% with placebo (P<0.001). Among previously treated patients, the rate of response was 50% with 12 weeks of treatment, as compared with 73% with 16 weeks of treatment (difference, -23 percentage points; 95% CI, -35 to -11; P<0.001). In both studies, response rates were lower among patients with genotype 3 infection than among those with genotype 2 infection and, among patients with genotype 3 infection, lower among those with cirrhosis than among those without cirrhosis. The most common adverse events were headache, fatigue, nausea, and insomnia; the overall rate of discontinuation of sofosbuvir was low (1 to 2%).
In patients with HCV genotype 2 or 3 infection for whom treatment with peginterferon and ribavirin was not an option, 12 or 16 weeks of treatment with sofosbuvir and ribavirin was effective. Efficacy was increased among patients with HCV genotype 2 infection and those without cirrhosis. In previously treated patients with genotype 3 infection, 16 weeks of therapy was significantly more effective than 12 weeks. (Funded by Gilead Sciences; POSITRON and FUSION ClinicalTrials.gov numbers, NCT01542788 and NCT01604850, respectively.).
Summary Background Interferon-free regimens are needed to treat hepatitis C virus (HCV) infections. We investigated the efficacy of combined simeprevir and sofosbuvir. Methods We enrolled patients ...with chronic HCV genotype 1 infections who had previously not responded to pegylated interferon (peginterferon) and ribavirin or were treatment naive. Patients were randomly assigned in a 2:1:2:1 ratio to receive 150 mg simeprevir and 400 mg sofosbuvir daily for 24 weeks with (group 1) or without (group 2) ribavirin or for 12 weeks with (group 3) or without (group 4) ribavirin, in two cohorts: previous non-responders with METAVIR scores F0–F2 (cohort 1) and previous non-responders and treatment-naive patients with METAVIR scores F3–F4 (cohort 2). The primary endpoint was sustained virological response 12 weeks after stopping treatment (SVR12). Analysis was done by intention to treat. Safety data from cohorts 1 and 2 were pooled for analysis. This study is registered with ClinicalTrials.gov , number NCT01466790. Findings 168 patients were enrolled and randomised, and 167 started treatment (n=80 in cohort 1 and n=87 in cohort 2). SVR12 was achieved in 154 (92%) patients (n=72 90%, 95% CI 81–96 in cohort 1 and n=82 94%, 87–98 in cohort 2). The most common adverse events in the pooled groups were fatigue (n=52 31%), headache (n=33 20%), and nausea (n=26 16%). Grade 4 adverse events were seen in one (2%) of 54 patients in each of groups 1 and 3 and in three (10%) of 31 patients in group 2, whereas grade 3–4 events were reported in less than 5% of all patients, except increased blood amylase concentration. Serious adverse events were seen in four (2%) patients, all in groups 1 and 2. Four (2%) patients discontinued all study treatment because of adverse events, three before week 12. Interpretation Combined simeprevir and sofosbuvir was efficacious and well tolerated. Funding Janssen.
Background & Aims Interferon alfa–based regimens used to treat recurrent hepatitis C virus (HCV) infection after liver transplantation are poorly tolerated, associated with generally modest efficacy, ...and can interact with immunosuppressive agents. We evaluated the efficacy and safety of an interferon-free regimen of the nucleotide polymerase inhibitor sofosbuvir combined with ribavirin for 24 weeks in treating post-transplantation HCV infection. Methods In a prospective, multicenter, open-label pilot study, we enrolled patients with compensated recurrent HCV infection of any genotype after a primary or secondary liver transplantation. All patients received 24 weeks of sofosbuvir 400 mg daily and ribavirin starting at 400 mg daily, which was adjusted according to creatinine clearance and hemoglobin values. The primary end point was sustained virologic response 12 weeks after treatment. Results Of the 40 patients enrolled and treated, 78% were male, 85% were white, 83% had HCV genotype 1, 40% had cirrhosis (based on biopsy), and 88% had been previously treated with interferon. Sustained virologic response 12 weeks after treatment was achieved by 28 of 40 patients (70%; 90% confidence interval: 56%−82%). Relapse accounted for all cases of virologic failure. No patients had detectable viral resistance during or after treatment. The most common adverse events were fatigue (30%), diarrhea (28%), and headache (25%). In addition, 20% of the subjects experienced anemia. Two patients discontinued study treatment because of adverse events, which were considered unrelated to study treatment. No deaths, graft losses, or episodes of rejection occurred. No interactions with any concomitant immunosuppressive agents were reported. Conclusions Sofosbuvir and ribavirin combination therapy for 24 weeks is an effective and well-tolerated interferon-free treatment for post-transplantation HCV infection. EudraCT, Number: 2012-002417-19; ClinicalTrials.gov , Number: NCT01687270.
Background & Aims Patients with detectable hepatitis C virus (HCV) RNA at the time of liver transplantation universally experience recurrent HCV infection. Antiviral treatment before transplantation ...can prevent HCV recurrence, but existing interferon-based regimens are poorly tolerated and are either ineffective or contraindicated in most patients. We performed a trial to determine whether sofosbuvir and ribavirin treatment before liver transplantation could prevent HCV recurrence afterward. Methods In a phase 2, open-label study, 61 patients with HCV of any genotype and cirrhosis (Child–Turcotte–Pugh score, ≤7) who were on waitlists for liver transplantation for hepatocellular carcinoma, received up to 48 weeks of sofosbuvir (400 mg) and ribavirin before liver transplantation. The primary end point was the proportion of patients with HCV-RNA levels less than 25 IU/mL at 12 weeks after transplantation among patients with this HCV-RNA level at their last measurement before transplantation. Results Sixty-one patients received sofosbuvir and ribavirin, and 46 received transplanted livers. The per-protocol efficacy population consisted of 43 patients who had HCV-RNA level less than 25 IU/mL at the time of transplantation. Of these 43 patients, 30 (70%) had a post-transplantation virologic response at 12 weeks, 10 (23%) had recurrent infection, and 3 (7%) died (2 from nonfunction of the primary graft and 1 from complications of hepatic artery thrombosis). Of all 61 patients given sofosbuvir and ribavirin, 49% had a post-transplantation virologic response. Recurrence was related inversely to the number of consecutive days of undetectable HCV RNA before transplantation. The most frequently reported adverse events were fatigue (in 38% of patients), headache (23%), and anemia (21%). Conclusions Administration of sofosbuvir and ribavirin before liver transplantation can prevent post-transplant HCV recurrence. ClinicalTrials.gov : NCT01559844.
Background & Aims We evaluated an all-oral regimen comprising the nucleotide polymerase inhibitor sofosbuvir (SOF) with the NS5A inhibitor ledipasvir (LDV) or the NS5B non-nucleoside inhibitor ...GS-9669 in patients with genotype 1 hepatitis C virus (HCV) infection. Methods A total of 113 patients were enrolled. Sofosbuvir (400 mg once daily) and LDV (90 mg once daily) plus ribavirin (RBV) were given for 12 weeks to treatment-naïve (TN) patients (n = 25) and those who did not respond to previous therapy (prior null responders, n = 9). Sofosbuvir and GS-9669 (500 mg once daily) plus RBV were given for 12 weeks to TN patients (n = 25) and prior null responders (n = 10). Additionally, prior null responders with cirrhosis were randomly assigned to groups given a fixed-dose combination of SOF and LDV, with RBV (n = 9) or without RBV (n = 10). Finally, a group of TN patients received SOF, LDV, and RBV for 6 weeks (n = 25). The primary efficacy end point was sustained virologic response 12 weeks after therapy (SVR12). Results SVR12 was achieved by 25 of 25 (100%) TN patients receiving SOF, LDV, and RBV and 23 of 25 (92%) of those receiving SOF, GS-9669, and RBV. Of TN patients receiving 6 weeks of SOF, LDV, and RBV, 17 of 25 (68%) achieved SVR12. All noncirrhotic prior null responders receiving 12 weeks of SOF along with another direct-acting antiviral agent plus RBV achieved SVR12—9 of 9 (100%) of those receiving SOF, LDV, and RBV and 10 of 10 (100%) of those receiving SOF, GS-9669, and RBV. Among cirrhotic prior null responders, SVR12 was achieved by 9 (100%) of those receiving SOF, LDV, and RBV and 7 (70%) of those receiving SOF and LDVD without RBV. The most common reported adverse events were headache, fatigue, and nausea. Conclusions The combination of SOF and a second direct-acting antiviral agent is highly effective in TN patients with HCV genotype 1 infection and in patients that did not respond to previous treatment. ClinicalTrials.gov ID NCT01260350.
Summary Background Compared with other countries, patients with chronic hepatitis C infection in Japan tend to be older, have more advanced liver disease, and are more likely to have been previously ...treated for hepatitis C. We aimed to assess the efficacy and safety of an all-oral, fixed-dose combination of the hepatitis C virus NS5A inhibitor ledipasvir and the NS5B nucleotide polymerase inhibitor sofosbuvir with and without ribavirin for 12 weeks in treatment-naive and previously treated Japanese patients with chronic genotype 1 hepatitis C virus infection. Methods In this randomised, open-label study, we enrolled patients from 19 clinical Japanese centres. Patients were randomly assigned (1:1) to receive either ledipasvir (90 mg) and sofosbuvir (400 mg) or ledipasvir, sofosbuvir, and ribavirin (dosed according to the Japanese Copegus product label—ie, patients ≤60 kg received 600 mg daily, patients >60 kg to ≤80 kg received 800 mg daily, and patients >80 kg received 1000 mg daily) orally once daily for 12 weeks. After completion or early discontinuation of treatment, patients were followed up off-treatment for 24 weeks. Eligible patients were at least 20 years of age with chronic genotype 1 hepatitis C virus infection with serum hepatitis C virus RNA concentrations of at least 5 log10 IU/mL, creatinine clearance of at least 1·0 mL/s, and a platelet count of at least 50 × 109 per L. An interactive web response system was used to manage patient randomisation and treatment assignment. Randomisation was stratified by the presence or absence of cirrhosis for treatment-naive patients and stratified by presence or absence of cirrhosis and by previous treatment category (relapser or breakthrough, non-responder, or interferon-intolerant) for previously treated patients. Within each strata, patients were sequentially assigned to either treatment with ledipasvir-sofosbuvir or ledipasvir-sofosbuvir plus ribavirin in a 1:1 ratio with block size of 4. The primary endpoint was sustained virological response 12 weeks after completion of treatment (SVR12) assessed in all patients who were randomly assigned and received at least one dose of study drug; safety outcomes were assessed in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov , number NCT01975675. Findings Between Oct 15, 2013 and Dec 13, 2013, 341 patients were randomly assigned to treatment groups and received at least one dose of study treatment. SVR12 was achieved in all 171 (100%) patients (83 of 83 treatment naive and 88 of 88 treatment experienced) receiving ledipasvir-sofosbuvir (95% CI 98–100) and 167 (98%) of 170 patients (80 of 83 treatment naive and 87 of 87 treatment experienced) receiving ledipasvir-sofosbuvir plus ribavirin (95% CI 95–100). Of the 76 patients with baseline NS5A resistant variants, 75 (99%) achieved SVR12. Two (1·2%) of 170 patients in the ledipasvir-sofosbuvir plus ribavirin group discontinued treatment because of adverse events. The most common adverse events were nasopharyngitis (50 29·2% of 171), headache (12 7·0% of 171), and malaise (nine 5·3% of 171) in patients receiving ledipasvir-sofosbuvir; and nasopharyngitis (40 23·5% of 170), anaemia (23 13·5% of 170), and headache in those receiving ledipasvir-sofosbuvir and ribavirin (15 8·8% of 170). Interpretation Although existing regimens for the treatment of hepatitis C virus are effective for many patients, medical needs remain unmet, particularly in Japan where the population with hepatitis C virus genotype 1 is generally older and treatment-experienced, with advanced liver disease. The efficacy, tolerability, and absence of drug–drug interactions of ledipasvir-sofosbuvir suggest that it could be an important option for treatment of genotype 1 hepatitis C virus in Japanese patients. Funding Gilead Sciences.
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