The Fixed Dose Combination of Sofosbuvir and Velpatasvir is Safe and Effective in Patients of Chronic Hepatitis C With End-stage Renal Disease

Background

The burden of hepatitis C virus (HCV) in India is alarming, with a major share of this virus being witnessed in patients with end-stage renal disease (ESRD). A pan-genotypic combination of sofosbuvir and velpatasvir is found to be safe, effective, and economical in resource-constraint countries such as ours. However, there are scanty data on the efficacy and safety of sofosbuvir and velpatasvir combination in patients with ESRD. Hence, we performed this study to evaluate the safety and efficacy of the combination of sofosbuvir and velpatasvir in patients of chronic hepatitis C (CHC) with ESRD.

Methods

This is an observational study comprising of 40 CHC patients with ESRD on maintenance hemodialysis. All patients were treated with a fixed-dose combination of sofosbuvir and velpatasvir for 12 weeks in case of non-cirrhotic or compensated cirrhosis and 24 weeks in case of decompensated cirrhosis. The efficacy was assessed by sustained virological response defined by negative HCV RNA at 12 weeks (sustained virological response [SVR] 12) post treatment, and safety was assessed by recording any side-effects of all patients.

Results

Out of the 40 patients enrolled in our study, majority were non-cirrhotic (77%), and all were treatment-naive. The mean age was 49.87 ± 12.13 years, and 80% patients were male. The mean baseline HCV RNA was 2.61 ± 7.83 × 106 IU/ml. All the 40 patients (100%) achieved undetectable HCV RNA at the end of treatment; however, 39 patients (97.5%) achieved SVR 12. There was no significant deterioration of estimated glomerular filtration rate (eGFR) after completion of antiviral therapy as compared to the baseline eGFR (13.27 ± 10.32 vs13.54 ± 11.38, P = 0.54). None of the patients reported any serious adverse effects during treatment.

Conclusion

The fixed-dose combination of sofosbuvir and velpatasvir is effective and has showed excellent safety profile in patients of CHC with ESRD.

Sofosbuvir/Velpatasvir/Voxilaprevir for Hepatitis C Virus Retreatment in Difficult-to-treat Patients: A Real-life Observational Study from India

Background and aim

Hepatitis C virus (HCV) treatment fails to achieve sustained virological response at 12 weeks (SVR12) in 5-10 % and requires retreatment with second-line drugs. We report our experience of sofosbuvir/velpatasvir/voxilaprevir use for HCV retreatment in a small cohort of difficult-to-treat Indian patients.

Methods

We reviewed our HCV databases to identify the patients who had failed to achieve SVR12 after treatment with sofosbuvir in combination with either daclatasvir, ledipasvir, or velpatasvir with/without ribavirin on one or more occasions. Participants were excluded if they had (i) decompensated cirrhosis, (ii) HIV coinfection or (iii) chronic kidney disease, or (iv) prior organ transplantation. All the participants were treated with sofosbuvir/velpatasvir/voxilaprevir plus ribavirin for 12 weeks. Treatment outcome was categorized as successful or failure if HCV RNA was undetectable or detectable at SVR12, respectively.

Results

Fifteen patients (male 67 %; genotype-3 80 %) were included in the analysis. Ten (67 %) had cirrhosis. Five, eight, and two participants had previously failed one, two, and three courses of pegylated-interferon free, sofosbuvir containing direct acting antiviral (DAA) regimens respectively. Fourteen participants had failed to at least one course of the sofosbuvir/velpatasvir combination. Fourteen patients achieved SVR12, and one patient was lost to follow-up. Treatment was successful in 100 % and 93.3 % of per-protocol (PP) and intention to treat (ITT) analyses, respectively.

Conclusion

Sofosbuvir/velpatasvir/voxilaprevir combination is an effective second-line therapy in India for difficult-to-treat HCV patients.

Pharmacokinetic evaluation of sofosbuvir/velpatasvir for the treatment of Chronic Hepatitis C in pediatrics aged 3 and older

INTRODUCTION

The World Health Organization proposed targets to eliminate hepatitis C virus (HCV) by 2030, aiming to treat ≥80% of people with HCV, decreasing new chronic infections by 90% and liver-related mortality by 65%. While children/adolescents represent a minority of cases, the true burden is underestimated. Advances in drug development have resulted in simplified treatments that are well-tolerated, effective, and pangenotypic in activity. Sofosbuvir/velpatasvir, a combined nucleotide analog NS5B polymerase inhibitor and NS5A inhibitor, respectively, is approved for HCV treatment for individuals ≥3 years, supported by safety data using lower-dose, novel formulations.

AREAS COVERED

This review discusses chemistry, pharmacokinetics/pharmacodynamics, dosing, efficacy, and safety of sofosbuvir/velpatasvir highlighting pediatric data. Literature review included publications/conference abstracts from PubMed, Google, and Google Scholar. Information from key clinical trials/regulatory approvals is reviewed.

EXPERT OPINION

Sofosbuvir/velpatasvir is a safe and effective therapy for the treatment of pangenotypic chronic HCV infection with limited cases of virologic relapse and adverse events among pediatric populations aged 3 years and older. However, the tolerability among children less than 6 years could be improved by alternative formulations, if not, shorter treatment durations. An aspirational role of direct-acting antivirals (DAAs) that should be explored is for the prevention of infection in exposed and at-risk pediatric populations.

Hepatitis C Retreatment With First-Line Direct Acting Antiviral Drugs

Background and Aims

Sofosbuvir (S), daclatasvir (D), ledipasvir, or velpatasvir (V) containing first-line hepatitis C virus (HCV) treatment regimens fail to cure viremia in 5-10%. We report our experience of HCV retreatment using these first-line drugs, in a setting where second-line anti-HCV drugs are not available.

Methods

Adults, who had relapsed after first complete course of a sofosbuvir-containing first-line, pegylated interferon free, anti-HCV treatment regimen with or without ribavirin (Riba) were included. Retreatment regimen, tailored to the failed anti-HCV regimen, was based on principle of using first-line drugs for 24 weeks with ribavirin and swapping between pangenotypic and genotype-specific regimens. Retreatment outcome was categorized as successful (achieved undetectable HCV RNA at the end of treatment [ETR] and sustained viral response at week 12 [SVR12]), non-responder (failed to achieve ETR), or relapse (achieved ETR but not achieved SVR12).

Results

Twelve patients (9 male; 7 cirrhosis; all genotype 3) who had relapsed to prior anti-HCV treatment (4 SD12, 4 SD24, 1 SDRiba12, 1 SDRiba24, 2 SV12) were included. Following retreatment (2 SDRiba24, 10 SVRiba24), all achieved ETR but only 9 (75%) achieved SVR12. Two among three, in whom retreatment failed, achieved SVR12 following another course of sofosbuvir/velpatasvir/ribavirin for 24 weeks. Overall, 11/12 (92%) patients achieved SVR12 following retreatment with the first-line anti-HCV drugs.

Conclusion

HCV retreatment could be a treatment option if second-line anti-HCV drugs are not available. Successful retreatment could be achieved, in a large proportion, with the use of first-line drugs for 24 weeks with ribavirin and swapping of pangenotypic/genotype-specific regimens (NCT03483987).

The tolerability of sofosbuvir/velpatasvir for 12 weeks in patients treated in the ASTRAL 1, 2 and 3 studies: A pooled safety analysis

To evaluate the safety and tolerability of the fixed-dose, single-tablet regimen sofosbuvir/velpatasvir (SOF/VEL) for the treatment of hepatitis C virus (HCV) infection in three Phase 3 studies in patients with and without compensated cirrhosis. Data from three registrational trials (ASTRAL-1, NCT02201940; ASTRAL-2, NCT02220998; ASTRAL-3, NCT02201953) were pooled by treatment regimen. Researchers assessed treatment-emergent adverse events (TEAEs) and laboratory abnormalities in patients randomized to SOF/VEL or placebo for 12 weeks in ASTRAL-1 and SOF/VEL for 12 weeks in ASTRAL-2 and ASTRAL-3. Overall, 1035 patients were treated with SOF/VEL, and 116 patients received placebo. Rates of any TEAE were generally similar between patients receiving SOF/VEL (79.4%) and those receiving placebo (76.7%). The majority of TEAEs were mild to moderate, with 23 (2.2%) treatment-emergent serious AEs in patients treated with SOF/VEL. Of these treatment-emergent serious AEs, none led to premature study discontinuation, nor were they considered related to treatment. Presence of compensated cirrhosis, greater age and mild renal impairment did not impact incidence or severity of TEAEs with SOF/VEL treatment. The most common TEAEs (incidence ≥10%) were headache, fatigue, nausea and nasopharyngitis in patients receiving SOF/VEL; similar rates were observed in placebo-treated patients. Three deaths (<1%) were reported in patients treated with SOF/VEL, all posttreatment and none assessed as related to study treatment. Similar to that of placebo, SOF/VEL treatment of HCV infection had a safety/tolerability profile that was not affected by baseline factors, such as the presence of compensated cirrhosis, mild renal impairment or advanced age.

Hepatitis C viral clearance with coadministration of crushed sofosbuvir/velpatasvir and high-dose pantoprazole after liver transplantation

DISCLAIMER

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

Direct-acting antivirals (DAAs) allow for successful transplantation of livers from hepatitis C nucleic acid test (NAT)-positive donors to negative recipients. However, limited data exist to support crushing DAAs in patients with multiple absorption concerns or significant drug interactions.

SUMMARY

Crushed sofosbuvir/velpatasvir has been successfully used in nontransplant patients with dysphagia, but data in transplant patients with absorption concerns are limited. A 31-year-old hepatitis C-negative female underwent liver transplantation from a hepatitis C NAT-positive donor. Her postoperative course was complicated by a mucormycosis infection, gastrointestinal bleed, and necrotizing pancreatitis requiring treatment with liposomal amphotericin B and pantoprazole 80 mg twice daily. Surgical interventions included an above-the-knee amputation and ileostomy. Hepatitis C treatment was initially delayed because of concern for reduced absorption with crushed DAA administration through the nasogastric (NG) tube, high ileostomy output, gastrointestinal bleed, pancreatitis, and a known drug interaction with pantoprazole. One month after transplantation, the patient's bilirubin level remained elevated and hepatitis C treatment was initiated with sofosbuvir/velpatasvir. Crushed sofosbuvir/velpatasvir was mixed with 30 mL of water and administered through the NG tube daily. Hepatitis C viral loads were obtained weekly during treatment to monitor efficacy. Although the patient died before evaluation of sustained virological response at 12 weeks, hepatitis C viral clearance was observed within 4 weeks of initiating treatment.

CONCLUSION

A liver transplant patient exhibited viral clearance of hepatitis C following administration of crushed sofosbuvir/velpatasvir in the setting of multiple absorption concerns.

Use of Sofosbuvir/Velpatasvir/Voxilaprevir for Sofosbuvir Nonresponder Genotype 3 HCV Infection in India

In India, hepatitis C virus (HCV) infection is treated with sofosbuvir in combination with NS5A inhibitor (Daclatasvir, Ledipasvir, or Velpatasvir). A small proportion of them fail to achieve sustained virological response at 12 weeks (SVR12) and need retreatment. Triple-drug combination (Sofosbuvir/Velpatasvir/Voxilaprevir) is one of the options for retreatment. Here we describe a patient with cirrhosis and genotype 3a infection who was successfully treated with a triple-drug combination after relapse with two courses of Sofosbuvir-containing regimens.

Sofosbuvir/velpatasvir with or without low-dose ribavirin for patients with chronic hepatitis C virus infection and severe renal impairment

OBJECTIVE

Data regarding the real-world effectiveness and safety of sofosbuvir/velpatasvir (SOF/VEL) with or without low-dose ribavirin (RBV) in patients with chronic hepatitis C virus (HCV) infection and severe renal impairment (RI) are limited. We evaluated the performance of SOF/VEL with or without low-dose RBV in HCV-infected patients with chronic kidney disease stage 4 or 5.

DESIGN

191 patients with compensated (n=181) and decompensated (n=10) liver diseases receiving SOF/VEL (400/100 mg/day) alone and SOF/VEL with low-dose RBV (200 mg/day) for 12 weeks were retrospectively recruited at 15 academic centres in Taiwan. The effectiveness was determined by sustained virological response at off-treatment week 12 (SVR₁₂) in evaluable (EP) and per-protocol populations (PP). The safety profiles were assessed.

RESULTS

The SVR₁₂ rates by EP and PP analyses were 94.8% (95% CI 90.6% to 97.1%) and 100% (95% CI 97.9% to 100%). In patients with compensated liver disease, the SVR₁₂ rates were 95.0% and 100% by EP and PP analyses. In patients with decompensated liver disease, the SVR₁₂ rates were 90.0% and 100% by EP and PP analyses. Ten patients who failed to achieve SVR₁₂ were attributed to non-virological failures. Among the 20 serious adverse events (AEs), none were judged related to SOF/VEL or RBV. The AEs occurring in ≥10% included fatigue (14.7%), headache (14.1%), nausea (12.6%), insomnia (12.0%) and pruritus (10.5%). None had ≥grade 3 total bilirubin or alanine aminotransferase elevations.

CONCLUSION

SOF/VEL with or without low-dose RBV is effective and well-tolerated in HCV-infected patients with severe RI.

Sofosbuvir plus velpatasvir combination for the treatment of chronic hepatitis C in patients with end stage renal disease on renal replacement therapy: A systematic review and meta-analysis

INTRODUCTION

Sofosbuvir (SOF) and velpatasvir (VEL) is a pan-genotypic regimen for the treatment of Hepatitis C virus (HCV) infection. The data on the efficacy and safety of this regimen is end-stage renal disease (ESRD) is scanty. This systematic review and meta-analysis was done to ascertain the efficacy and safety of SOF and VEL in patients with chronic Hepatitis C (CHC) and ESRD on renal replacement therapy (RRT).

METHODS

Systematic search of Pubmed, Embase, Scopus, and Google Scholar was conducted using the search term (end-stage renal disease OR renal replacement therapy OR chronic kidney failure OR severe renal impairment OR chronic kidney disease OR haemodialysis OR dialysis OR peritoneal dialysis) AND (sofosbuvir OR velpatasvir OR NS5A inhibitors OR directly acting antivirals). Pooled sustained virologic response (SVR) and adverse event rates with 95% confidence intervals were estimated.

RESULTS

Seven studies (410 patients with CHC and ESRD on RRT) fulfilled our eligibility criteria. The overall pooled SVR rate of SOF and VEL in patients with HCV on RRT was 97.69% (95% CI: 95.71 to 98.92). There was no significant heterogeneity (I² : 39.3%, p-value of Cochran's Q = 0.13) among the studies. The pooled estimate of efficacy of SOF-VEL combination among patients with cirrhosis was 91.94% (95% CI 77.03-98.52). Pooled SVR rates in genotype 3 infection [94.6%, (95%: CI 81.3-99.4)] was comparable to that in those with documented non-genotype 3 infection [94.63%, (95% CI 87.12-98.44)]. No serious adverse event attributable to SOF and VEL was reported in the included studies.

CONCLUSION

The fixed-dose combination of SOF and VEL is effective and safe in CHC patients with ESRD on RRT.

Sofosbuvir/velpatasvir plus ribavirin for Child-Pugh B and Child-Pugh C hepatitis C virus-related cirrhosis

Background/Aims

Real-world studies assessing the effectiveness and safety of sofosbuvir/velpatasvir (SOF/VEL) plus ribavirin (RBV) for Child-Pugh B/C hepatitis C virus (HCV)-related cirrhosis are limited.

Methods

We included 107 patients with Child-Pugh B/C HCV-related cirrhosis receiving SOF/VEL plus RBV for 12 weeks in Taiwan. The sustained virologic response rates at off-treatment week 12 (SVR₁₂) for the evaluable population (EP), modified EP, and per-protocol population (PP) were assessed. Thesafety profiles were reported.

Results

The SVR₁₂ rates in the EP, modified EP and PP were 89.7% (95% confidence interval [CI], 82.5–94.2%), 94.1% (95% CI, 87.8–97.3%), and 100% (95% CI, 96.2–100%). Number of patients who failed to achieve SVR₁₂ were attributed to virologic failures. The SVR₁₂ rates were comparable regardless of patient characteristics. One patient discontinued treatment because of adverse events (AEs). Twenty-four patients had serious AEs and six died, but none were related to SOF/VEL or RBV. Among the 96 patients achieving SVR₁₂, 84.4% and 64.6% had improved Child-Pugh and model for end-stage liver disease (MELD) scores. Multivariate analysis revealed that a baseline MELD score ≥15 was associated with an improved MELD score of ≥3 (odds ratio, 4.13; 95% CI, 1.16–14.71; P=0.02). Patients with chronic kidney disease (CKD) stage 1 had more significant estimated glomerular filtration rate declines than patients with CKD stage 2 (-0.42 mL/min/1.73 m²/month; P=0.01) or stage 3 (-0.56 mL/min/1.73 m²/month; P<0.001).

Conclusions

SOF/VEL plus RBV for 12 weeks is efficacious and well-tolerated for Child-Pugh B/C HCV-related cirrhosis.

Sofosbuvir-Based Therapies Achieved Satisfactory Virological Response in Chinese Individuals with Genotypes 3 and 6 Infections: A Real-World Experience

Background

Previous studies have shown that sofosbuvir-based regimens yield high sustained virological response rates in patients with hepatitis C virus (HCV) infection except for genotype 3b complicated with cirrhosis. This real-world study aims to explore the efficacy and safety of sofosbuvir-based regimens in Chinese patients with genotypes 3 and 6 infections, especially the impact of ribavirin coadministration on sustained virological response in cirrhotic patients with genotype 3b infection.

Methods

This is a retrospective cohort study that included 101 patients initiated on sofosbuvir-based regimens. The main endpoint of treatment was sustained virological response at posttreatment week 12 (SVR12).

Results

Overall, the SVR12 rates were 95.0% (96/101); specifically, the rates were 100% in sofosbuvir, 88.2% in sofosbuvir+ribavirin, 100% in sofosbuvir+daclatasvir, 100% in sofosbuvir+daclatasvir+ribavirin, 95.0% in sofosbuvir/velpatasvir, and 97.1% in sofosbuvir/velpatasvir+ribavirin (p=0.534). The SVR12 rates were comparable in patients infected with genotypes 3 and 6 (93.2% versus 97.6%, p=0.339). The SVR12 rate was 93.9% in cirrhotic patients (31/33). Among those infected with genotype 3, the SVR12 rate was 91.7% (22/24); the rate was 95.0% in those with ribavirin coadministration regimens, which was numerically higher than the 75.0% in those without ribavirin. However, no statistical difference was found (p=0.312). In total, five patients failed to achieve SVR12, including 3 patients with genotype 3b infection treated with ribavirin coadministration regimens (one of them was cirrhotic), 1 cirrhotic patient with genotype 3k infection, and 1 noncirrhotic patient with genotype 6a infection. No severe adverse event occurred.

Conclusion

Real-world data show that sofosbuvir-based regimens are highly effective and safe for patients with HCV genotypes 3 and 6 infections.

Hepatitis C: A Pharmacological Therapeutic Update

(1) Background: Hepatitis C is a high-prevalence disease, representing a global impact health problem. Lately, many changes have been made in treatment guidelines because of the commercialization of second-generation direct-acting antivirals due to their high effectiveness, few side effects and pangenotypic action. We address the pharmacological possibilities available and compare them with the current recommendations of the World Health Organization (WHO). (2) Methods: The search for articles was made through the PubMed database using different search strategies and we consulted technical data sheets of the treatments that have been included in the study. (3) Results: Combinations of “glecaprevir/pibrentasvir”, “sofosbuvir/velpatasvir” and “sofosbuvir/velpatasvir/voxilaprevir” have been recently incorporated. Phase II studies have shown that they are safe and effective therapies with very comfortable posologies and easy therapeutic adherence; furthermore, they suppose shorter treatment duration. Subsequently, phase III studies have shown they were effective for previously treated or compensated cirrhotic patients that previously had more complex treatment regimens. (4) Conclusions: These results suppose a simplification in Hepatitis C therapeutic approach, and open new study possibilities.

Cost-effectiveness analysis of sofosbuvir and velpatasvir in chronic hepatitis C patients with decompensated cirrhosis

BACKGROUND

Current literature indicates that direct-acting antivirals (DAAs) are cost-effective to treat compensated cirrhotic patients with hepatitis C. Although already funded by public payers, it is unknown whether it is economical to reimburse DAAs within the more advanced decompensated cirrhosis population.

METHODS

A state-transition model was developed to conduct a cost-utility analysis of sofosbuvir-velpatasvir (SOF/VEL) plus ribavirin regimen for 12 weeks. The evaluated cohort had a mean age of 58 years and Child-Turcotte-Pugh (CTP) class B cirrhosis with decompensated symptoms. A scenario analysis was performed on CTP C patients. We used a payer perspective, a lifetime time horizon and a 1.5% annual discount rate.

RESULTS

While SOF/VEL plus ribavirin treatment for 12 weeks increased costs by $156 676, it provided an extra 4.00 quality-adjusted life years (QALYs) compared to best supportive care (no DAA therapy). With an incremental cost-effectiveness ratio of $39 169 per QALY, SOF/VEL plus ribavirin was determined to be cost-effective at a willingness to pay of $50 000 per QALY. SOF/VEL reduced liver-related deaths and reduced progression to CTP C cirrhosis by 20.4% and 21.9%, respectively. On the contrary, SOF/VEL regimen resulted in increases in liver transplants and hepatocellular carcinoma (HCC) by 54.0% and 42.5%, respectively. Similar results were found for CTP C patients.

CONCLUSION

This analysis informs payers that SOF/VEL should continue to be reimbursed in decompensated hepatitis C patients. It also supports the recommendations by the American Association for the Study of Liver Diseases to continue screening for HCC in decompensated cirrhotic patients who have achieved sustained virologic response.

Real-world efficacy and safety of 12-week sofosbuvir/velpatasvir treatment for patients with decompensated liver cirrhosis caused by hepatitis C virus infection

AIM

This study aimed to evaluate the real-world efficacy and safety of 12-week sofosbuvir/velpatasvir (SOF/VEL) treatment for patients with decompensated liver cirrhosis caused by hepatitis C virus (HCV) infection.

METHODS

A total 72 of patients with Child-Pugh (CP) class B or C were enrolled. We evaluated the sustained virologic response at 12 weeks after the end of treatment (SVR12), adverse events (AEs), and changes in the liver function.

RESULTS

All participants had genotype 1 or 2 HCV infection. At baseline, the numbers of patients with CP class B and C were 59 and 13, respectively. The overall SVR12 rate was 95.8% (69/72); 94.9% (56/59) in CP class B and 100% (13/13) in CP class C. The serum albumin level, prothrombin time and ascites were significantly improved (P < 0.01); however, the serum bilirubin level and encephalopathy did not improve. Among patients who achieved SVR12, 75.0% showed an improvement in their CP score, while 5.9% showed a worsening. The presence of large portosystemic shunt (diameter ≥6 mm) and hyperbilirubinemia (≥2.0 mg/dL) were independent factors that interfered with the improvement in the CP score (P < 0.05). The most common AEs were encephalopathy (15.3%) and skin symptoms (7.9%). Two patients discontinued SOF/VEL due to AEs.

CONCLUSIONS

Treatment with SOF/VEL for 12 weeks was relatively safe and effective for patients with decompensated cirrhosis. An SVR provided an improvement of the liver function in the majority of patients. However, large portosystemic shunt and hyperbilirubinemia were independent factors that interfered with the improvement in the CP score.

Real-world efficacy of sofosbuvir plus velpatasvir therapy for patients with hepatitis C virus-related decompensated cirrhosis

AIM

Combination therapy with sofosbuvir (SOF) plus velpatasvir (VEL) is approved for patients with hepatitis C virus (HCV)-related decompensated cirrhosis. We analyzed the real-world efficacy of SOF/VEL therapy.

METHODS

Thirty-three patients with HCV-related decompensated cirrhosis (25 and eight patients with Child B and C, respectively) were treated with SOF/VEL for 12 weeks. The HCV non-structural protein (NS)5A and NS5B drug resistance-associated substitutions (RASs) were determined by direct sequencing.

RESULT

Thirty-two of 33 patients completed the treatment, but the remaining patient discontinued the therapy during third week of the treatment due to aggravation of hepatic encephalopathy. Serum HCV-RNA became negative during the treatment in all patients but relapsed after the end of therapy in five patients. In total, 28 out of 33 patients (85%) achieved sustained virological response 12 weeks following completion of treatment (SVR12). The SVR12 rate was 96% in patients with Child B, but significantly lower, at 50%, in patients with Child C (P < 0.05). In genotype 1b HCV-infected patients, all eight patients without baseline NS5A RASs, but only three of seven patients with RASs, achieved SVR12. Multivariate analysis identified Child B (odds ratio, 35.8 for Child C; P = 0.045) as an independent predictor of SVR12. Median serum albumin levels significantly increased only in patients who achieved SVR12. Child-Pugh scores improved in 16 of 28 patients (57%) following achievement of SVR12.

CONCLUSION

The effect of SOF/VEL therapy is lower for patients with Child C. Improvement of hepatic function is expected after viral eradication with SOF/VEL therapy in patients with decompensated cirrhosis.

Efficacy and Safety of Generic Sofosbuvir Plus Daclatasvir and Sofosbuvir/Velpatasvir in HCV Genotype 3-Infected Patients: Real-World Outcomes From Pakistan

BACKGROUND

Direct-acting antivirals (DAAs) therapeutic regimens are highly effective against chronic hepatitis C virus (HCV) infection. However, HCV patients with genotype 3 (GT3) respond in a suboptimal way. This study aims to identify which of the DAAs-based therapeutic regimens are the best option for GT3.

METHODS

Multiple governments and private tertiary care hospitals were involved in this real-life study of HCV-GT3 patients treated with DAAs. The efficacy and safety of generic sofosbuvir+daclatasvir±ribavirin (SOF+DCV±RBV) and sofosbuvir/velpatasvir±ribavirin (SOF/VEL±RBV) were assessed under the National Hepatitis C Program of Pakistan.

RESULTS

Out of 1,388 participants, 70% of patients received SOF+DCV in government tertiary care hospitals and 30% received SOF/VEL in private tertiary care hospitals. The overall sustained virological responses (SVR) was 95.5%. The SVR rates at 12 weeks were comparable between SOF+DCV (94.4%) and SOF/VEL (94.7%) in chronic HCV patients. However, The SVR rates at 24 weeks were high in cirrhotic patients treated with SOF/VEL+RBV (88%) then SOF+DCV+RBV (83%). Non-responders were high in SOF-DCV than SOF-VEL (4.1 vs 3.8%, P = 0.05) regimen. In multivariate models, the significant predictors of non-SVR were age >60 years (odds ratio [OR] 4.46; 95% CI, 2.35-8.46, P = <0.001) and cirrhosis (OR 53.91; 95% CI, 26.49-109.6, P = <0.001). Skin rash (51 vs 44%) and oral ulcers (45 vs 40%) were high in patients receiving SOF-DCV then SOF-VEL.

CONCLUSIONS

Overall, the generic SOF+DCV ±RBV and SOF/VEL ± RBV achieved equally high SVR12 rates. However, SOF/VEL+RBV achieved a high SVR rate in cirrhotic patients then SOF+DCV+RBV. Old age and cirrhosis were significant predictors of reduced odds of SVR regardless of the regimen. Furthermore, the regimens were well tolerated in chronic HCV patients.

Sofosbuvir-Velpatasvir Fixed Drug Combination for the Treatment of Chronic Hepatitis C Infection in Patients With End-Stage Renal Disease and Kidney Transplantation

INTRODUCTION

India is witnessing high hepatitis C virus (HCV) infection burden in patients of chronic kidney disease. Due to unavailability of costly Kidney Disease Improving Global Outcomes-recommended directly acting antiviral drugs, a widely available pan-genotypic combination of Sofosbuvir and Velpatasvir can become an economical option. Data regarding treatment experience of sofosbuvir-velpatasvir combination in chronic kidney disease is scarce. No data from India have been published in patients on renal replacement therapies till now.

METHODS

This retrospective analysis included all patients of end-stage renal disease on maintenance hemodialysis with treatment-naïve chronic HCV infection treated with sofosbuvir (400 mg) and velpatasvir (100 mg) fixed-dose combination. Pretreatment routine investigations were performed, which included HCV viral load, genotype, fibro scan, endoscopy for esophageal varices, and portal vein Doppler. The patients were followed up with HCV viral load to declare sustained virologic response.

RESULT

patients were included with a mean age of 39.8 ± 10.8 years, and 77.4% were male. Genotype 1 was found to be most prevalent (67.7%), with a median viral load of 106copies/ml. Six (19.3%) patients had hepatitis B virus co-infection. Three (9.7%) patients had cirrhosis. Sustained virologic response (SVR12) was achieved in 30 (96.8%) patients, and one (3.2%) patient had relapse. Furthermore, 14 (45.2%) patients underwent renal transplantation, and none of them had relapsed. Dyspepsia (9.7%) was the most common side effect observed with no major adverse effect.

CONCLUSION

Our study showed excellent efficacy with the safety profile of this drug combination in end-stage renal disease patients. However, larger prospective studies and multicenter randomized controlled trials are needed for further confirmation.

Thin-layer chromatography/fluorescence detection approach for sensitive and selective determination of hepatitis C virus antiviral (velpatasvir): application to human plasma

A validated thin-layer chromatography (TLC) method combined with fluorescence detection mode was developed for the selective determination of a recently approved anti-hepatitis C virus (HCV) drug (velpatasvir). The separation was performed on silica gel 60 F₂₅₄ plates using ethylacetate:methanol:triethylamine (48:1.5:1.0, v/v/v) as a mobile phase. Plates were scanned in the fluorescence mode after excitation at 335 nm. This method provided an excellent separation of velpatasvir from sofosbuvir with R_F values of 0.22 and 0.46 for velpatasvir and sofosbuvir, respectively, after scanning the developed plates in the ultraviolet detection mode at 335 nm. The calibration curve was linear over the range 4-40 ng/band with a correlation coefficient of 0.9994. The developed procedure was validated according to ICH guidelines with a detection limit of 1.30 ng/band and quantitation limit of 3.95 ng/band. The suggested method could selectively determine velpatasvir with high sensitivity in a synthetic tablet powder containing a co-formulated anti-HCV drug (sofosbuvir) without any interference from excipients or sofosbuvir. In addition, the method was successfully applied for determination of velpatasvir in spiked human plasma with adequate % recovery.

Comparison of three therapeutic regimens for genotype-3 hepatitis C virus infection in a large real-life multicentre cohort

BACKGROUND & AIMS

In the direct-acting antiviral era, treatment of genotype-3 HCV (HCV-GT3) is still challenging. Real-life comparisons between recommended regimens, sofosbuvir (SOF)+daclatasvir (DAC), SOF/velpatasvir (VEL), glecaprevir/pibrentasvir (GLE/PIB), are scarce. We aimed at filling this data gap.

METHODS

Sustained virological response 12 weeks after treatment completion (SVR12) was assessed for all HCV-GT3 patients consecutively treated within the Lombardia web-based Navigatore HCV-Network; differences in SVR12 across regimens were evaluated by logistic regression.

RESULTS

Of the 2082 subjects with HCV-GT3, 1544 were evaluable for comparisons between regimens: SOF + DAC (1023, 66.2%), SOF/VEL (369, 23.9%), GLE/PIB (152, 9.8%). Patients treated with former regimens were more frequently male, cirrhotic, HIV-positive, pretreated, used ribavirin in their regimen, and had lower baseline HCV-RNA. SVR12 was similar across groups: 94.8% in SOF + DAC, 97.6% in SOF/VEL, 96.7% in GLE/PIB (P = .065). At univariate analysis, SVR12 was associated with female gender (97.9% vs 94.8%, P = .007) and lower median pretreatment Log₁₀ HCV-RNA (5.87 vs 6.20, P = .001). At multivariate logistic regression analysis, treatment with SOF/VEL was associated with a higher likelihood of SVR12 than SOF + DAC, but only in the absence of ribavirin (98% vs 90.3%). Female gender and lower pretreatment HCV-RNA were independently associated with SVR12.

CONCLUSIONS

In a large real-life setting of HCV-GT3-infected patients with a high proportion of cirrhosis, the success rate was remarkable. The slight advantage of SOF/VEL on SOF + DAC was significant only without ribavirin. The current prescription shift towards novel regimens (ie SOF/VEL and GLE/PIB) in easier-to-treat patients allows ribavirin-free and shorter schedules without mining SVR12 in this <<difficult-to-treat>> genotype.

Eight weeks of sofosbuvir/velpatasvir for genotype 3 hepatitis C in previously untreated patients with significant (F2/3) fibrosis

Twelve weeks sofosbuvir/velpatasvir (SOF/VEL) is a highly effective pan-genotypic regimen for hepatitis C. Phase 2 data suggest 8 weeks of treatment may be sufficient for previously untreated noncirrhotic patients with genotype 3 (GT3) infection. To maximize the number of patients potentially cured within a fixed treatment budget, we elected to treat such patients locally eligible for treatment (F2/3), with 8 weeks of SOF/VEL. By local protocol, treatment-naive patients with F2 (LSM > 6.9kPa < 9.5kPa) or F3 fibrosis (≥9.5kPa < 12.5kPa) were eligible for 8-week SOF/VEL treatment. Patients commencing treatment before 1 Oct 2017 were identified from the Scottish HCV database. Baseline and treatment outcome data obtained. Ninety patients were included for analysis (72 (80%) male, mean age 45 (IQR ± 8.4), 28 (31.1%) F3 fibrosis). Opioid agonist therapy (OAT) was prescribed in 82 (91.1%) patients. Of 49 patients attending Glasgow city Alcohol and Drug Services, 27 (55.1%) had evidence of recent drug use (< 3 months) including 8 (16.3%) with self-reported intravenous drug use. On an intention-to-treat basis, SVR rates were 86/90 (95.6%, 95% CI 89.0-98.8). Excluding those who prematurely discontinued treatment (n = 4), died prior to SVR testing (n = 1) or whom experienced reinfection (n = 1), per-protocol SVR rate was 84/84 (100%, 95% CI 95.7-100.0). In conclusion, eight-week SOF/VEL is highly effective in treatment-naive GT3 patients with significant fibrosis. This offers a non-protease inhibitor-based 8-week regimen which may be useful for complex drug interactions or where time-limited opportunity for treatment. In limited resource settings, reduction in drug acquisition costs may help achieve progress towards the goal of HCV elimination.

In-Vitro and In-Vivo Evaluation of Velpatasvir- Loaded Mesoporous Silica Scaffolds. A Prospective Carrier for Drug Bioavailability Enhancement

The limited aqueous solubility of many active pharmaceutical ingredients (APIs) is responsible for their poor performance and low drug levels in blood and at target sites. Various approaches have been adopted to tackle this issue. Most recently, mesoporous silica nanoparticles (MSN) have gained attention of pharmaceutical scientists for bio-imaging, bio-sensing, gene delivery, drug solubility enhancement, and controlled and targeted drug release. Here, we have successfully incorporated the poorly water soluble antiviral drug velpatasvir (VLP) in MSN. These spherical particles were 186 nm in diameter with polydispersity index of 0.244. Blank MSN have specific surface area and pore diameter of 602.5 ± 0.7 m2/g and 5.9 nm, respectively, which reduced after successful incorporation of drug. Drug was in amorphous form in synthesized VLP-loaded silica particles (VLP-MSN) with no significant interaction with carrier. Pure VLP showed poor dissolution with progressive increment in pH of dissolution media which could limit its availability in systemic circulation after oral administration. After VLP loading in silica carriers, drug released rapidly over a wide range of pH values, i.e., 1.2 to 6.8, thus indicating an improvement in the solubility profile of VLP. These particles were biocompatible, with an LD50 of 448 µg/mL, and in-vivo pharmacokinetic results demonstrated that VLP-MSN significantly enhanced the bioavailability as compared to pure drug. The above results clearly demonstrate satisfactory in-vitro performance, biocompatibility, non-toxicity and in-vivo bioavailability enhancement with VLP-MSN.

Real-world Effectiveness of Sofosbuvir/Velpatasvir for Treatment of Chronic Hepatitis C in British Columbia, Canada: A Population-Based Cohort Study

Background

Clinical trials show high efficacy of sofosbuvir/velpatasvir (SOF/VEL), but there are limited data from “real-world” settings. We aimed to evaluate SOF/VEL effectiveness for all hepatitis C virus (HCV) genotypes (GTs) in British Columbia (BC), Canada.

Methods

We used the BC Hepatitis Testers Cohort, which includes all HCV cases in the province (1990–2015) linked to administrative databases, including prescriptions to end of 2018. We measured sustained virologic response (SVR; negative RNA ≥10 weeks after treatment end) and identified characteristics associated with non-SVR. Conservatively, we excluded individuals with no assessment for SVR if their last RNA test after treatment initiation was negative (but included if positive).

Results

Of 2821 eligible participants, most were infected with GT1 (1076, 38.1%) or GT3 (1072, 38.0%), and a minority (278, 9.9%) were treated with RBV. SVR was 94.6% (2670/2821) overall and 94.5% (1017/1076) for GT1, 96.4% (512/531) for GT2, and 93.7% (1004/1072) for GT3. When disaggregated by GT, treatment regimen, and cirrhosis/treatment experience, SVR was lowest (30/40, 75.0%) among treatment-experienced GT3 individuals treated with RBV. Characteristics associated with non-SVR in multivariable analysis included younger age, RBV addition, and being a person with HIV (PWH) or who injects/injected drugs (PWID). When treatment regimen (±RBV) was removed from multivariable model, treatment experience was associated with non-SVR for GT3. Of 151 non-SVR individuals, 56.3% were nonvirological failures (treatment incomplete/no assessment for SVR) and 43.7% were virological failures (nonresponse/relapse). A disproportionately high percentage of non-SVR among PWID was due to nonvirological failure.

Conclusions

SOF/VEL was highly effective in this “real-world” population-based cohort. Additional support is required for PWID/PWH to reach SVR.

Pharmacokinetics, Safety, and Tolerability of Ledipasvir/Sofosbuvir and Sofosbuvir/Velpatasvir in Healthy Chinese Subjects

PURPOSE

Ledipasvir/sofosbuvir and sofosbuvir/velpatasvir have been approved worldwide for the treatment of chronic hepatitis C virus (HCV) infection. Although both have been approved in China, there are currently no data on their pharmacokinetic profiles in Chinese individuals. Two studies investigated the pharmacokinetic properties, safety, and tolerability of ledipasvir/sofosbuvir and sofosbuvir/velpatasvir, respectively, in healthy Chinese subjects.

METHODS

Two Phase I, open-label, single- and multiple-dose studies were conducted in healthy Chinese subjects. Ledipasvir/sofosbuvir (90/400 mg) or sofosbuvir/velpatasvir (400/100 mg), respectively, was administered orally once daily under fasted conditions. Subjects received a single dose (day 1) and multiple doses (days 8-17 [ledipasvir/sofosbuvir]; days 8-14 [sofosbuvir/velpatasvir]). Plasma pharmacokinetic parameters were estimated by using noncompartmental models, and safety was assessed through clinical evaluation and monitoring of adverse events.

FINDINGS

Fourteen subjects were enrolled in each study (7 men, 7 women each; mean age, 30 years [ledipasvir/sofosbuvir] and 29 years [sofosbuvir/velpatasvir]). The pharmacokinetic parameters for sofosbuvir, GS-566500, GS-331007, and ledipasvir or velpatasvir were similar to historical values in non-Chinese subjects. Consistent with the t_1/2 of ledipasvir relative to 24-h dosing, accumulation of 177% (AUC) and 107% (C_max) was observed. There was no significant accumulation of velpatasvir, sofosbuvir, GS-566500, or GS-331007. Both drugs were generally well tolerated; no serious adverse events or discontinuations due to adverse events were reported.

IMPLICATIONS

Overall, ledipasvir/sofosbuvir and sofosbuvir/velpatasvir exhibited pharmacokinetic and safety profiles in healthy Chinese subjects similar to those in non-Chinese subjects in historical studies, supporting their use in the Chinese population with HCV infection. ChinaDrugTrials.org.cn identifiers: CTR20160149 (ledipasvir/sofosbuvir); CTR20160602 (sofosbuvir/velpatasvir).

Prediction of the SARS-CoV-2 (2019-nCoV) 3C-like protease (3CL pro) structure: virtual screening reveals velpatasvir, ledipasvir, and other drug repurposing candidates

We prepared the three-dimensional model of the SARS-CoV-2 (aka 2019-nCoV) 3C-like protease (3CL pro) using the crystal structure of the highly similar (96% identity) ortholog from the SARS-CoV. All residues involved in the catalysis, substrate binding and dimerisation are 100% conserved. Comparison of the polyprotein PP1AB sequences showed 86% identity. The 3C-like cleavage sites on the coronaviral polyproteins are highly conserved. Based on the near-identical substrate specificities and high sequence identities, we are of the opinion that some of the previous progress of specific inhibitors development for the SARS-CoV enzyme can be conferred on its SARS-CoV-2 counterpart.  With the 3CL pro molecular model, we performed virtual screening for purchasable drugs and proposed 16 candidates for consideration. Among these, the antivirals ledipasvir or velpatasvir are particularly attractive as therapeutics to combat the new coronavirus with minimal side effects, commonly fatigue and headache.  The drugs Epclusa (velpatasvir/sofosbuvir) and Harvoni (ledipasvir/sofosbuvir) could be very effective owing to their dual inhibitory actions on two viral enzymes.

Prediction of the SARS-CoV-2 (2019-nCoV) 3C-like protease (3CL pro) structure: virtual screening reveals velpatasvir, ledipasvir, and other drug repurposing candidates

We prepared the three-dimensional model of the SARS-CoV-2 (aka 2019-nCoV) 3C-like protease (3CL pro) using the crystal structure of the highly similar (96% identity) ortholog from the SARS-CoV. All residues involved in the catalysis, substrate binding and dimerisation are 100% conserved. Comparison of the polyprotein PP1AB sequences showed 86% identity. The 3C-like cleavage sites on the coronaviral polyproteins are highly conserved. Based on the near-identical substrate specificities and high sequence identities, we are of the opinion that some of the previous progress of specific inhibitors development for the SARS-CoV enzyme can be conferred on its SARS-CoV-2 counterpart.  With the 3CL pro molecular model, we performed virtual screening for purchasable drugs and proposed 16 candidates for consideration. Among these, the antivirals ledipasvir or velpatasvir are particularly attractive as therapeutics to combat the new coronavirus with minimal side effects, commonly fatigue and headache.  The drugs Epclusa (velpatasvir/sofosbuvir) and Harvoni (ledipasvir/sofosbuvir) could be very effective owing to their dual inhibitory actions on two viral enzymes.

Effectiveness and safety of sofosbuvir/velpatasvir ± ribavirin vs glecaprevir/pibrentasvir in genotype 3 hepatitis C virus infected patients

Objectives

Sofosbuvir/velpatasvir±ribavirin (SOF/VEL±RBV) and glecaprevir/pibrentasvir (GLE/PIB) are the drug combinations of choice for treating individuals with genotype 3 hepatitis C virus (G3-HCV) infection. The objective of this study was to evaluate the effectiveness and safety of SOF/VEL±RBV compared with GLE/PIB for treating G3-HCV infection under routine clinical practice conditions.

Methods

We conducted a prospective observational cohort study of individuals with G3-HCV infection who initiated treatment with SOF/VEL +/-RBV or GLE/PIB between April 2017 and July 2018. Prisoners and children were excluded. The outcome variable of effectiveness was sustained virological response 12 weeks after completing treatment (SVR12). The safety variable was withdrawal secondary to severe adverse events (SAEs). Covariates included sex, age, HIV co-infection, previous liver transplant, cirrhosis, hepatic fibrosis and previous antiviral treatment. Statistical significance was calculated using Fisher's exact test or the Mann-Whitney U-test.

Results

A total of 76 patients were included in the analysis, of whom 46 were treated with SOF/VEL±RBV and 30 were treated with GLE/PIB. No baseline differences were observed between treatment groups with respect to age, sex, HIV co-infection, fibrosis stage, cirrhosis and previous antiviral treatment. Of the patients treated with SOF/VEL±RBV and GLE/PIB, 95.7% and 96.7% reached SVR12, respectively (P=0.7). Of patients with and without cirrhosis, 83.3% and 98.4% reached SVR12, respectively (P=0.09). Of the patients with low-grade hepatic fibrosis (F0-2) and advanced fibrosis (F3-4), 100% and 85.7% reached SVR12, respectively (P=0.03). In treatment-naïve and treatment-experienced patients, 95.7% and 100% reached SVR12, respectively (P=0.57), without significant differences independent of the treatment group (P=0.28 for SOF/VEL±RBV; P=0.18 for GLE/PIB). The incidence of AEs was 21.1% (95% CI 11.3% to 30.9%). None of the patients developed an SAE or required antiviral treatment withdrawal.

Conclusions

SOF/VEL±RBV or GLE/PIB are safe and effective for treating G3-HCV-infections, with a lower effectiveness in patients with advanced fibrosis F3-4.

Developments in the treatment of HCV genotype 3 infection

Introduction: Unlike other hepatitis C virus (HCV) genotypes (GTs), patients infected with GT3 are associated with an increased risk of accelerated liver disease progression. Although early immuno-modulator therapies yielded moderate sustained virologic response (SVR) rates, treatment of GT3 patients has proven more challenging in the era of direct-acting antivirals (DAAs). Areas covered: The review provides an overview of the evolution of therapies against GT3 since the approval of the first immunomodulatory agent nearly 30 years ago. Expert opinion: A greater choice of treatment options is now available for HCV GT3-infected patients. In treatment-naïve patients with or without compensated cirrhosis, SVR rates are comparably high approaching 100% irrespective of treatment option. For treatment-experienced patients, choosing the right therapy is important, especially for those with advanced liver disease. For the few patients who fail with multiple persistent highly resistant DAA substitutions, retreatment options are limited. Additional real-world treatment comparisons are required to confirm differences in SVR in these more difficult-to-treat patients. This also includes patients infected with GT3 subtypes such as GT3b where multiple DAA-resistant substitutions occur naturally. In the absence of new drugs with non-overlapping drug-resistant profiles, an interferon-based therapy may still be beneficial in select patient populations with high-level multiple DAA-resistant substitutions.

In vitro resistance profile of hepatitis C virus NS5A inhibitor velpatasvir in genotypes 1 to 6

Velpatasvir is a pan-genotypic hepatitis C virus (HCV) NS5A inhibitor, which is used with sofosbuvir for treatment of infection with HCV genotypes 1-6. In vitro resistance studies were performed to characterize NS5A changes that might confer reduced velpatasvir susceptibility in vivo. Resistance selection studies using HCV replicon cells for subtypes 1a, 1b, 2a, 2b, 3a, 4a, 5a and 6a identified NS5A resistance-associated substitutions (RASs) at nine positions, most often 28M/S/T, 31F/I/M/P/V and 93D/H/N/S. In subtype 1a, RASs were selected at positions 31 and/or 93, while in subtype 1b, replicons with two or more RASs at positions 31, 54 or 93 were selected. Y93H was selected in subtypes 1a, 1b, 2a, 3a and 4a. In subtype 5a or 6a, L31P or P32L/Q was selected, respectively. Velpatasvir susceptibility of 358 replicons from genotypes 1 to 6 containing one or more NS5A RASs was also evaluated. The majority (63%) of subtypes 1a and 1b single RAS-containing replicons retained susceptibility to velpatasvir (<2.5-fold change in EC₅₀ ). High levels of resistance to velpatasvir were observed for six single mutants in subtype 1a, including M28G, A92K, Y93H/N/R/W and for one mutant, A92K, in subtype 1b. Most single mutants in subtypes 2a, 2b, 3a, 4a and 5a displayed low levels of reduced velpatasvir susceptibility. High-level resistance was observed for C92T and Y93H/N in subtype 2b, Y93H/S in 3a, and L31V and P32A/L/Q/R in 6a, and several double mutants in these subtypes. Overall, velpatasvir maintained activity against most common RASs that are known to confer resistance to first-generation NS5A inhibitors.

Successful early sofosbuvir-based antiviral treatment after transplantation of kidneys from HCV-viremic donors into HCV-negative recipients

BACKGROUND

Transplanting kidneys from deceased donors with hepatitis C virus (HCV) viremia has been controversial for some time. Direct-acting antiviral agents have been shown to be highly effective in treating HCV infection. We report our experience with transplanting kidneys from HCV-positive donors with detectable viremia into HCV-negative recipients, followed by early treatment with a sofosbuvir-based antiviral regimen.

METHODS

Data were collected from seven HCV-negative recipients receiving kidneys from five deceased HCV-viremic donors. Before transplantation, all intentional transplanted recipients had given informed consent regarding the acceptance of an HCV-viremic kidney. Recipients were closely monitored after transplant with measurements of HCV viremia, liver and renal function, and trough levels of immunosuppressive drugs.

RESULTS

Four donors were infected with HCV genotype 1; the other with HCV genotype 3a. HCV viremia was detectable in all seven renal transplant recipients within 3 days after transplant. After determination of HCV genotype, antiviral treatment with a sofosbuvir-based regimen (sofosbuvir/ledipasvir, n = 4; sofosbuvir/velpatasvir, n = 3) was initiated within a median of 7 days after transplantation and was continued for 8 to 12 weeks. For all recipients, viral load was below the level of detection at the end of treatment, and all exhibited a sustained virologic response 12 weeks later. All recipients exhibited normal liver enzyme activity at the end of treatment. Renal allograft function and trough levels of tacrolimus remained stable.

CONCLUSIONS

Early administration of a sofosbuvir-based regimen to HCV-negative recipients of kidneys from HCV-viremic donors is feasible and safe. The definition of an optimal therapeutic approach warrants further investigation.

Impact of Preexisting Hepatitis C Virus Genotype 6 NS3, NS5A, and NS5B Polymorphisms on the In Vitro Potency of Direct-Acting Antiviral Agents

HCV genotype 6 (GT-6) is found predominantly in East and Southeast Asia. Clinical studies have focused on patients infected with hepatitis C virus (HCV) GT-6a, where high sustained virologic response (SVR) rates to direct-acting antivirals (DAAs) have been achieved. However, GT-6 is highly diverse, with 29 reported subtypes. We explored the diversity of GT-6 polymorphisms at residues associated with DAA resistance, their impact on DAA in vitro potency when evaluated in a GT-6a consensus replicon, and their association with specific GT-6 subtypes. GT-6 sequences from 25 patient-derived samples and 105 sequences from the U.S. HCV database were compared, and substitutions at resistance-associated residue positions were phenotyped against different DAAs. Preexisting resistance-associated substitutions (RASs) to NS3 protease (A156V and D168E) and NS5B nucleotide (L159F and S282C) inhibitors were rare (<4%). Preexisting RASs to NS5A inhibitors were common, especially at L28 (A/F/G/M/T/V) and R30 (E/N/S). In vitro susceptibilities of NS5A-L28A and -L28T were dramatically reduced against all tested NS5A drugs (90% effective concentration [EC₉₀] range, 119 to 2,032 nM) compared with susceptibilities against a GT-6a consensus replicon (EC₉₀ range, 0.1 to 19 nM). These L28 RASs preexisted in combination with R30S (EC₉₀ [L28A-R30S] of ≥720 nM or EC₉₀ [L28T-R30S] of ≥128 nM against tested DAAs) or as L28T-L31I (EC₉₀ [tested DAAs] of >5,000 nM) and were detected in evaluated GT-6b and -6f sequences. NS5A-L28A-R30A, observed in GT-6r, did not replicate. In conclusion, HCV GT-6b, GT-6f, and GT-6r sequences harbored highly resistant RASs to all evaluated NS5A drugs. Therefore, monitoring SVR in patients infected with these GT-6 subtypes treated with NS5A drug-containing regimens is suggested to confirm any association between noted NS5A polymorphisms and treatment failure.

Identification of 19 Novel Hepatitis C Virus Subtypes-Further Expanding HCV Classification

Background

Hepatitis C virus (HCV) is currently classified into 8 genotypes and 86 subtypes. The objective of this study was to characterize novel HCV subtypes and to investigate the impact of subtypes on treatment outcome.

Methods

Full-genome sequencing was performed on HCV plasma samples with <85% sequence homology of NS3, NS5A, and/or NS5B to HCV genotype (GT) 1–8 reference strains.

Results

A total of 14 653 patients with GT1–6 HCV infection were enrolled in clinical studies of sofosbuvir-based regimens. For the majority of the patients, a specific subtype could be assigned based on a close genetic relationship to previously described subtypes. However, for 19 patients, novel subtypes were identified with <85% homology compared with previously described subtypes. These novel subtypes had the following genotypes: 9 in GT2, 5 in GT4, 2 in GT6, and 1 each in GT1, GT3, and GT5. Despite the presence of polymorphisms at resistance-associated substitution positions, 18 of the 19 patients treated with sofosbuvir-containing therapy achieved SVR12.

Conclusions

Nineteen novel HCV subtypes were identified, suggesting an even greater genetic diversity of HCV subtypes than previously recognized.

Treating HCV Infection: It Doesn't Get Much Better Than This

Direct-acting antiviral (DAA) regimens now allow treatment of previously untreated or treated (including prior DAA failures) patients with chronic hepatitis C virus (HCV) infection with 8 or 12 week regimens, largely without the use of ribavirin. Newer next-generation pan-genotypic regimens with activity against resistance-associated substitutions include glecaprevir/pibrentasvir (GLE/PIB), a combination of a nonstructural protein (NS)3 protease inhibitor and an NS5A inhibitor, and sofosbuvir/velpatasvir/voxilaprevir (SOF/VEL/VOX), a combination of an NS5B polymerase inhibitor, NS5A inhibitor, and NS3 protease inhibitor. Both regimens have indications in DAA-experienced patients. GLE/PIB is approved for treatment of patients with genotype 1, 2, 3, 4, 5, or 6 infection without cirrhosis or with compensated cirrhosis and for the treatment of patients with genotype 1 infection previously treated with a regimen containing an NS5A inhibitor or an NS3/4A protease inhibitor, but not the combination. SOF/VEL/VOX is approved for retreatment of patients without cirrhosis or with compensated cirrhosis with genotype 1, 2, 3, 4, 5, or 6 infection previously treated with an NS5A inhibitor-containing regimen, or with genotype 1a or 3 previously treated with a SOF-containing regimen without an NS5A inhibitor. This article summarizes an IAS-USA webinar given by Susanna Naggie, MD, MHS, on August 30, 2018.

Real-World Efficacy and Safety of Pangenotypic Direct-Acting Antivirals Against Hepatitis C Virus Infection

BACKGROUND

Advances in the development of Direct-Acting Antivirals (DAAs), particularly pangenotypic drugs, have led to a high rate of hepatitis C virus (HCV) eradication. Notably, real- world studies have confirmed the efficacy and safety of pangenotypic DAA combinations reported in registration trials. The aim of this study was to review the treatment recommendations, and the efficacy and safety data of anti-HCV pangenotypic drugs reported in registration clinical trials and in recent real-life cohort studies.

METHODS

We reviewed the efficacy and safety data of pangenotypic anti-HCV drug combinations reported in original articles and in online conference abstracts.

RESULTS

Current pangenotypic drug combinations resulted in very high rates of sustained virologic response and few adverse reactions in real-life settings. SVR12 rates in real-life studies ranged from 90-100% depending on the pangenotypic combination, the HCV genotype and the stage of liver disease. Most adverse reactions reported in real-life settings were mild in intensity and rarely led to treatment discontinuation. These results are in accordance with those of clinical trials.

CONCLUSION

Pangenotypic DAAs result in very high rates of sustained virologic responses and are well tolerated. However, they are contraindicated in patients with decompensated cirrhosis or advanced chronic kidney disease who failed previous DDA-based treatment. Further research is required to customize treatment to "unpackage" current DAA combinations and to develop generic drugs against HCV.

Sofosbuvir, velpatasvir and voxilaprevir: a new triple combination for hepatitis C virus treatment. One pill fits all? Is it the end of the road?

The advent of oral direct-acting antiviral agents (DAAs) has dramatically improved the hepatitis C virus (HCV) treatment landscape in the last 4 years, providing cure rates over 95% with a shorter duration of treatment and a very good safety profile. This has enabled access to treatment in nearly all HCV infected patients. The launch of two pangenotypic fixed dose combinations (FDCs) in 2017 made a new step forward in HCV treatment by slightly increasing efficacy and more importantly allowing the treatment of patients without HCV genotyping, and in some cases without fibrosis assessment. However, retreatment of the few DAA failure patients was still an issue for some HCV genotypes. The launch of the triple regimen FDC, sofosbuvir/velpatasvir/voxilaprevir, solves this issue by providing a cure rate over 96% regardless of HCV genotype. In this review, we describe the current HCV treatment landscape and focus on the development of this triple FDC either in treatment-naïve or treatment-experienced patients with previous failure on a DAA regimen.

Successful treatment of genotype 3 hepatitis C infection in a noncirrhotic HIV infected patient on chronic dialysis with the combination of sofosbuvir and velpatasvir: A case report

RATIONALE

Data on anti-HCV therapy in patients on dialysis is still evolving. Sofosbuvir is mainly eliminated through the renal route and there is controversy about its use in these patients.

PATIENT CONCERNS

We describe a 53-year-old male patient with HCV genotype 3 and human immunodeficiency type 1 (HIV) infection on chronic dialysis. HIV infection was diagnosed in 1987 and since July 2007 the patient was compliant with his antiretroviral therapy (ART) and had an undetectable plasma HIV viral load on all follow-up measurements. The patient was known to have HCV infection since 1997 but has never been treated for chronic hepatitis C. Because of progressive renal impairment dialysis started in 2005.

DIAGNOSIS

Before anti-HCV treatment commenced the patient liver transient elastography (FibroScan) indicated F3 fibrosis (stiffness, 11.6 kPa) and his HCV RNA viral load was 320,798 IU/mL (Abbott RealTime HCV assay).

INTERVENTION

Fixed dose combination of sofosbuvir/velpatasvir (400 mg/100 mg) for 11 weeks.

OUTCOMES

Twelve weeks after treatment cessation HCV RNA was undetectable, hence the patient achieved a sustained virologic response. The drugs were well tolerated and the patient did not report any side effects.

LESSONS

Sofosbuvir/velpatasvir may be an option for HCV genotype 3 infection in patients coinfected with HIV on long-term dialysis.

Sofosbuvir/velpatasvir for the treatment of HCV: excellent results from a phase-3, open-label study in Russia and Sweden

BACKGROUND

In both Russia and Sweden, the dominant hepatitis C virus (HCV) is genotype 1, but around one-third of patients have genotype 3 infection. For such countries, HCV genotype testing is recommended prior to therapy. An effective pangenotypic therapy may potentially eliminate the need for genotyping. In this study, we evaluated the efficacy and safety of sofosbuvir/velpatasvir for 12 weeks in patients from Russia and Sweden.

METHODS

In an open-label, single-arm phase-3 study, patients could have HCV genotype 1-6 infection and were treatment-naïve or interferon treatment-experienced. All patients received sofosbuvir/velpatasvir, once daily for 12 weeks. The primary endpoint was sustained virologic response 12 weeks post-treatment (SVR12).

RESULTS

Of 122 patients screened, 119 were enrolled and treated. Overall, half (50%) were male, 18% had cirrhosis, and 24% had failed prior interferon-based therapy. In total, 66% of patients were infected with HCV genotype 1 (59% 1b and 7% 1a), 6% with genotype 2, and 29% with genotype 3. The overall SVR12 rate was 99% (118/119, 95% confidence interval 95-100%). One treatment-experienced patient infected with HCV genotype 3 experienced virologic relapse after completing treatment. The most common adverse events were headache (16%) and fatigue (7%). Serious adverse events were observed in four patients, but none were related to treatment. No patients discontinued treatment due to adverse events.

CONCLUSION

Sofosbuvir/velpatasvir as a pangenotypic treatment for 12 weeks was highly effective in patients from Russia and Sweden infected with HCV genotypes 1, 2, or 3. Sofosbuvir/velpatasvir was safe and well-tolerated. Clinical trial number: ClinicalTrials.gov NCT02722837.

The pharmacological interactions between direct-acting antivirals for the treatment of chronic hepatitis c and psychotropic drugs

INTRODUCTION

Most direct-acting antivirals (DAAs) and psychotropic drugs are metabolized by or induct/inhibit CYP enzymes and drug transporters. Although they are frequently coadministered, the drug-drug interactions (DDIs) have been little studied. Therefore, the aim of this review is to describe the interactions between the approved DAA or combination regimens and the main psychoactive substances, including legal and illegal drugs of abuse. Areas covered: We performed a literature search on PubMed database on drug interactions with the currently available antivirals for hepatitis C and a review of the information on pharmacokinetics, metabolism, and drug interactions from www.hep-druginteractions.org and from all the Summary of Product Characteristics (SmPC). This review covers the DDI between the DAA regimens approved, such as simeprevir and sofosbuvir, paritaprevir, glecaprevir, voxilaprevir, ombitasvir, ledipasvir, daclatasvir and sofosbuvir, elbasvir and grazoprevir, sofosbuvir and velpatasvir, glecaprevir/pibrentasvir, sofosbuvir and velpatasvir, and main psychotropic agents. Expert Commentary: DAA regimens based on sofosbuvir combination usually have less DDI than protease inhibitor-based regimens. Among protease inhibitors regimens, new combinations, such as glecaprevir/elbasvir and grazoprevir/elbasvir, seemed to have less DDI than the combination POrD (paritaprevir/ombitasvir/ritonavir/dasabuvir). However, the analysis of each interaction is theoretical and further interaction studies would be necessary to confirm actual effect.

Study on fluorescence properties of HCV antiviral (velpatasvir) and its fluorimetric determination in presence of sofosbuvir; application to stability study and human plasma

Velpatasvir (VLP) is a new, oral, direct-acting antiviral with potent inhibitory activity against all hepatitis C virus (HCV) genotypes. A highly sensitive, simple, fast and specific one fluorometric method for determination of VLP in the presence of sofosbuvir was developed and validated. The fluorescence behavior of VLP in different organic solvents was examined and explained. Methanol was concluded to be the best sensitizing reagent. The native fluorescence intensity of VLP was accomplished at 383 nm with 339 nm for excitation wavelength. The impacts of experimental variables included pH, various organized media, and time of stability were examined and optimized. A linear relationship was achieved between the VLP concentration and the fluorescence intensity in a range of 5 to 5 × 10³ ng mL^-1 with 0.70 and 0.23 ng mL^-1 , for quantitation and detection limits respectively. The proposed method was utilized for analyzing of VLP in human plasma and additionally expanded to examine the stability of VLP after its exposure to various stress conditions, like oxidative, alkaline, acidic, UV, daylight and sunlight conditions, according to ICH guidelines. Furthermore, the kinetics of acidic and oxidative degradations of VLP was examined. Moreover, the half-life times of the reaction (t_1/2 ) and the first-order reaction rate constants were estimated. Finally, a suggestion for the degradation pathway was presented.

Novel determination of sofosbuvir and velpatasvir in human plasma by UPLC-MS/MS method: Application to a bioequivalence study

A novel and sensitive LC-MS/MS method was developed, optimized and validated for quantification of sofosbuvir (SOF) and velpatasvir (VEL) in human plasma using ledipasvir as an internal standard (IS). Sample preparation was done using acetonitrile for precipitation of plasma proteins. Chromatographic analysis was done on an Acquity UPLC BEH C₁₈ column using 0.1% formic acid and acetonitrile as a mobile phase. The Xevo TQD LC-MS/MS system was run with electrospray ionization mode. The developed method was optimized and then validated according to the US Food and Drug Administration guidelines. Linearity was found to be in the range of 0.25-3500 ng/mL for SOF and 1-1000 ng/mL for VEL. A short run time of 1.5 min allows swift analysis of many plasma samples per day. The developed method was successfully utilized for estimating both SOF and VEL in the plasma of healthy human volunteers participated in a bioequivalence study.

Sofosbuvir + velpatasvir + voxilaprevir for the treatment of hepatitis C infection

INTRODUCTION

Hepatitis C is a disease with a significant global impact. Over the last several years, the treatment of the disease has been revolutionized. Therapy has transformed over the last several years with the approval of second generation direct acting antivirals, and currently utilized medications for the treatment of hepatitis C are significantly more efficacious with better safety profiles than previously approved treatments. Treatment for individuals who have failed therapy on direct acting antivirals has, until recently, been complex and difficult to treat, but the approval of sofosbuvir/velpatasvir/voxilaprevir represents a new therapeutic option for these individuals. Areas covered: Sofosbuvir/velpatasvir/voxilaprevir is a recently approved therapeutic combination for the treatment of hepatitis C. This article reviews the studies leading to the approval of the combination, and its efficacy and safety profile. Expert opinion: Sofosbuvir/velpatasvir/voxilaprevir fills one of the previously unfilled niches for the treatment of hepatitis C, that of the treatment of individuals who have failed therapy with resistant virus. With the filling of this niche, there appears to be a general slowing of the development of new therapeutics. Although understandable, in the long term, there are considerable risks associated with the decreased development of new drugs to treat hepatitis C.

Sofosbuvir-Based Direct-Acting Antiviral Therapies for HCV in People Receiving Opioid Substitution Therapy: An Analysis of Phase 3 Studies

Background

Hepatitis C virus (HCV) direct-acting antiviral therapy is effective among people receiving opioid substitution therapy (OST), but studies are limited by small numbers of nongenotype 1 (GT1) patients. The aim of this study was to evaluate the treatment completion, adherence, SVR12, and safety of sofosbuvir-based therapies in HCV patients receiving and not receiving OST.

Methods

Ten phase 3 studies of sofosbuvir-based regimens included ION (ledipasvir/sofosbuvir ± ribavirin for 8, 12, or 24 weeks in GT1), ASTRAL (sofosbuvir/velpatasvir for 12 weeks in GT1-6), and POLARIS (sofosbuvir/velpatasvir and sofosbuvir/velpatasvir/voxilaprevir in GT1-6). Patients with clinically significant drug use (last 12 months) or noncannabinoids detected at screening were ineligible.

Results

Among 4743 patients, 4% (n = 194) were receiving OST (methadone; n = 113; buprenorphine, n = 75; other, n = 6). Compared with those not receiving OST (n = 4549), those receiving OST (n = 194) were younger (mean age, 48 vs 54), more often male (73% vs 61%), GT3 (38% vs 17%), treatment-naïve (78% vs 65%), and cirrhotic (36% vs 23%). Among those receiving and not receiving OST, there was no significant difference in treatment completion (97% vs 99%, P = .06), SVR12 (94% vs 97%, P = .06), relapse (0.5% vs 2.1%, P = .19), adverse events (78% vs 77%, P = .79), or serious adverse events (3.6% vs 2.4%, P = .24). There was no difference in SVR12 in patients with cirrhosis (99% vs 95%, P = .25) or those with G3 (95% vs 95%, P = .77) in those receiving OST. Among patients receiving OST, SVR12 was high among those receiving methadone (95%) and buprenorphine (96%).

Conclusion

Sofosbuvir-based therapies are effective and safe in patients receiving OST.

Resistance characterization of ledipasvir and velpatasvir in hepatitis C virus genotype 4

HCV genotype 4 (GT4) has often been overlooked in drug development, even though it infects ~20 million people worldwide. Ledipasvir/sofosbuvir and sofosbuvir/velpatasvir were highly efficacious in GT4 HCV-infected patients from GS-US-337-1119 and GS-US-342-1138. Here, we characterize the resistance profile of ledipasvir (LDV) and velpatasvir (VEL) in patients with GT4 HCV infection. NS5A deep-sequencing was performed for 454 patients infected with HCV GT4 at baseline, including 44 patients enrolled in GS-US-337-1119 and 116 patients enrolled in GS-US-342-1138, and at relapse for patients with virologic failure. LDV and VEL susceptibilities of 56 patient isolates were determined. In GS-US-337-1119, SVR12 rates were 100% for all subtypes except 4b and 4r. Phenotypic assessment of 56 HCV NS5A patient isolates from various GT4 subtypes indicated that LDV had high potency for the common subtypes 4a/d, and subtypes 4c/f/k/l/m/n/o/p/r/t despite the presence of resistance-associated substitutions (RASs). For the rare GT4b, LDV median EC₅₀ was higher, but with a broad range of individual values. Importantly, all GT4b isolates tested had 2-4 NS5A RASs, some including Y93H. Similarly, the 2 GT4r infected patients who had virologic relapse had rare triple RASs. Reversion of these substitutions to the consensus residue significantly increased LDV susceptibility. In GS-US-342-1138, all patients achieved SVR12, regardless of their subtype or presence of RASs. In vitro data confirmed that VEL is potent against all GT4 isolates tested. LDV and VEL are potent antiviral drugs, estimated to be effective against >95% and >99%, respectively, of GT4 HCV isolates.

Evaluation of sofosbuvir, velpatasvir plus voxilaprevir as fixed-dose co-formulation for treating hepatitis C

INTRODUCTION

The fixed-dose combination of three direct-acting antivirals (DAA), namely sofosbuvir, velpatasvir and voxilaprevir is the first pangenotypic, single tablet regimen developed for the treatment of HCV infection. Areas covered: The pharmacokinetics, pharmacodynamics, efficacy and safety of the co-formulation are reviewed. Information on drug absorption, distribution, metabolism and excretion of each of the three antivirals is evaluated. Finally, antiviral activity, safety and potential for drug interactions in phase II/III clinical trials in distinct patient populations are discussed. Expert opinion: The triple co-formulation of sofosbuvir-velpatasvir-voxilaprevir represents a major step towards HCV eradication. It depicts high efficacy even in patients infected with viruses harboring resistance-associated substitutions (RAS), including those selected after DAA failures. Likewise, very high success rates and good tolerance are seen in special patient populations, including decompensated cirrhotics, HIV coinfection, organ transplantation or renal insufficiency. A pill once daily for 8 weeks gives SVR rates above 95%. In prior DAA failures, extending treatment to 12 weeks maximizes SVR rates.

Sofosbuvir and Velpatasvir for the Treatment of Hepatitis C Virus in Patients Coinfected With Human Immunodeficiency Virus Type 1: An Open-Label, Phase 3 Study

BACKGROUND

A safe, simple, effective, and pan-genotypic regimen to treat hepatitis C virus (HCV) infection in patients coinfected with human immunodeficiency virus type 1 (HIV-1) remains a medical need. We assessed the efficacy and safety of the NS5B polymerase inhibitor sofosbuvir and the NS5A inhibitor velpatasvir for HCV in patients coinfected with HIV-1.

METHODS

This phase 3, open-label, single-arm study at 17 sites in the United States enrolled patients with HCV of any genotype and HIV-1 coinfection, including those with compensated cirrhosis. All patients received sofosbuvir-velpatasvir once daily for 12 weeks. The primary endpoint was sustained virologic response 12 weeks after treatment (SVR12). Efficacy and safety were assessed in all patients receiving at least 1 dose of treatment.

RESULTS

Of 106 patients, 91 (86%) were men, 48 (45%) were black, and 19 (18%) had cirrhosis. SVR12 was achieved by 101 of 106 (95% [95% confidence interval {CI}, 89%-99%]) patients: 74 of 78 (95% [95% CI, 87%-99%]) with genotype 1; all 11 (100% [95% CI, 72%-100%]) with genotype 2; 11 of 12 (92% [95% CI, 62%-100%]) with genotype 3; and all 5 (100% [95% CI, 48%-100%]) with genotype 4. All 19 patients with cirrhosis had SVR12. Two patients relapsed, 2 were lost to follow-up, and 1 withdrew consent. Two discontinued treatment due to adverse events and 2 had serious adverse events. The most common adverse events were fatigue (25%), headache (13%), upper respiratory tract infection (8%), and arthralgia (8%).

CONCLUSIONS

Sofosbuvir-velpatasvir for 12 weeks was safe and provided high rates of SVR12 in patients coinfected with HCV and HIV-1.

CLINICAL TRIALS REGISTRATION

NCT02480712.

Sofosbuvir and velpatasvir for the treatment of hepatitis C

Direct acting antivirals are revolutionizing the treatment of chronic hepatitis C. Specifically, the combination therapy sofosbuvir and velpatasvir offers a pangenotypic regimen with high sustained viral response (SVR). Areas covered: Reviewed here are the clinical trials that led to the FDA approval of sofosbuvir and velpatasvir combination therapy, the adverse events during registration trials, and drug-drug interactions. Sofosbuvir and velpatasvir is a fixed dose regimen that is both interferon- and ribavirin-free. It is administered for 12 weeks as a once-a-day pill, covers all genotypes of hepatitis C, and achieves SVR >95% in non-cirrhotic patients and patients with compensated cirrhosis. Addition of ribavirin is recommended for patients with decompensated cirrhosis (CTP B or C). Baseline resistance-associated substitutions do not appear to impair ability to achieve SVR with an initial course of treatment. Expert commentary: Availability of this highly efficacious, well tolerated, all oral regimen formulated as a single pill, can potentially simplify hepatitis C treatment. Its utility as a pangenotypic regimen additionally limits resource utilization.

Preclinical Pharmacokinetics and First-in-Human Pharmacokinetics, Safety, and Tolerability of Velpatasvir, a Pangenotypic Hepatitis C Virus NS5A Inhibitor, in Healthy Subjects

Preclinical characterization of velpatasvir (VEL; GS-5816), an inhibitor of the hepatitis C virus (HCV) NS5A protein, demonstrated that it has favorable in vitro and in vivo properties, including potent antiviral activity against hepatitis C virus genotype 1 to 6 replicons, good metabolic stability, low systemic clearance, and adequate bioavailability and physicochemical properties, to warrant clinical evaluation. The phase 1 (first-in-human) study evaluated the safety, tolerability, and pharmacokinetics of VEL in healthy human subjects following administration of single and multiple (n = 7) once-daily ascending doses and of VEL in the presence and absence of food. Following administration of single and multiple doses, VEL was safe and well tolerated when administered at up to 450 mg and when administered with food. The pharmacokinetic behavior of VEL observed in humans was generally in agreement with that seen during preclinical characterization. Following administration of multiple doses, VEL trough concentrations were significantly greater than the protein-adjusted half-maximal (50%) effective concentration of VEL against HCV genotype 1 to 6 replicons at all evaluated doses greater than 5 mg. The pharmacokinetics of VEL were not significantly affected by administration with food. Collectively, the results of this study support the further clinical investigation of VEL administered once daily as part of a regimen with other pangenotypic direct-acting antivirals for the treatment of HCV infection.

Sofosbuvir/velpatasvir regimen promises an effective pan-genotypic hepatitis C virus cure

Hepatitis C virus (HCV) is a global pandemic, with nearly 200 million infected patients worldwide. HCV is the most common blood-borne infection in the US with numerous health implications including liver fibrosis, cirrhosis, and hepatocellular cancer. Traditional genotype-based HCV therapies with interferon resulted in moderate success in the sustained elimination of viral genome. Recent clinical trials of the once-daily combination tablet of sofosbuvir, a nonstructural (NS) 5B polymerase inhibitor, and velpatasvir, an NS5A inhibitor, demonstrate sustained virologic response rates of about 95%, regardless of prior treatment experience or presence of cirrhosis across all HCV genotypes. Patients reported improvements in general health, fatigue, and emotional and mental well-being after completing combination therapy. The combination treatment is effective, but does need to be administered with caution in patients receiving certain medications or with certain diseases. Herein, we review the safety and efficacy of sofosbuvir/velpatasvir combination regimen for all HCV genotypes.