Efficacy and safety of glecaprevir/pibrentasvir in treatment-naïve adults with chronic hepatitis C virus genotypes 1-6 in Brazil

Revolutionizing hepatitis C treatment: next-gen direct-acting antivirals

INTRODUCTION

With the introduction of highly effective and safe therapies with next-generation direct-acting antivirals (DAAs), that act without interferon, hepatitis C virus (HCV) infection remains the only treatable chronic infectious disease.

AREAS COVERED

The review aims to provide an overview of the therapy revolution with a description of specific DAAs, their mechanisms of action, a summary of the safety and efficacy of specific regimens, and a discussion of populations requiring special therapeutic approaches.

EXPERT OPINION

DAAs are highly effective, safe, and easy to use. However, challenges such as access to health services and loss of patients from the cascade of care, especially in groups disproportionately affected by HCV infection, such as substance abusers, make it difficult to achieve the WHO's goal of HCV elimination. The proposed strategy to combat these difficulties involves a one-step approach to diagnosing and treating the infection, the availability of long-lasting forms of medication, and the development of an effective vaccine. The aforementioned opportunities are all the more important as the world is facing an opioid epidemic that is translating into an increase in HCV prevalence. This phenomenon is of greatest concern in women of childbearing age and in those already pregnant due to treatment limitations.

Hepatitis C

Hepatitis C virus (HCV) is a hepatotropic RNA virus that can cause acute and chronic hepatitis, with progressive liver damage resulting in cirrhosis, decompensated liver disease, and hepatocellular carcinoma. In 2016, WHO called for the elimination of HCV infection as a public health threat by 2030. Despite some progress, an estimated 57 million people were living with HCV infection in 2020, and 300 000 HCV-related deaths occur per year. The development of direct-acting antiviral therapy has revolutionised clinical care and generated impetus for elimination, but simplified and broadened HCV screening, enhanced linkage to care, and higher coverage of treatment and primary prevention strategies are urgently required.

Safety analysis of glecaprevir/pibrentasvir in patients with markers of advanced liver disease in clinical and real-world cohorts

Chronic hepatitis C virus (HCV) infection has the greatest health impact in patients with advanced liver disease. The direct-acting antiviral (DAA) regimen glecaprevir/pibrentasvir (G/P) is approved for treatment of HCV-infected patients without cirrhosis and with compensated cirrhosis. However, events of liver decompensation/failure have been reported in patients treated with protease-inhibitor-containing DAA regimens, often in patients with advanced liver disease. This study examines the safety of on-label G/P treatment in patients with compensated cirrhosis (F4 at baseline) with markers of advanced liver disease. Patients with cirrhosis were categorized into 4 subgroups, based on different noninvasive markers of advanced liver disease identified using laboratory measures: platelet count < or ≥ 100 × 10⁹ /L, and Child-Pugh score 5 or 6. Separate analyses were performed using pooled data from clinical trials and from real-world post-marketing observational studies. G/P was well tolerated in patients with platelet count ≥100 × 10⁹ /L (n = 800), platelet count <100 × 10⁹ /L (n = 215), a Child-Pugh score of 5 (n = 915) and a Child-Pugh score of 6 (n = 95). In the clinical trial and real-world cohorts two patients and no patients experienced a serious adverse event (AE) possibly related to study drug, respectively; three patients and no patients experienced an AE of special interest for hepatic decompensation and hepatic failure. This analysis reaffirms G/P's safety profile in indicated patients with compensated cirrhosis, including those with markers of more advanced liver disease. Increasing the number of patients treated with short-duration G/P therapy may contribute to meeting HCV elimination targets.

Antiviral drugs

In this chapter, we have reviewed side effects reported with the use of antivirals for the treatment of the following infections: coronavirus disease 2019 (COVID-19), cytomegalovirus (CMV), hepatitis B virus (HBV), hepatitis C Virus (HCV), herpes simplex viruses 1 and 2 (HSV-1, -2), human immunodeficiency virus (HIV), and influenza virus. The search engines PUBMED, EMBASE and International Pharmaceutical Abstracts (IPA) were utilized to identify literature published between January 1, 2021 to December 31, 2021.

Efficacy and Safety of 8- or 12 Weeks of Glecaprevir/Pibrentasvir in Patients with Evidence of Portal Hypertension

INTRODUCTION

High efficacy and safety of 8-week glecaprevir/pibrentasvir (G/P) therapy was seen in hepatitis C (HCV)-infected, treatment-naïve (TN), compensated cirrhosis (CC) patients in EXPEDITION-8. To provide further understanding of the efficacy of G/P treatment in HCV-infected TN patients with CC and clinical evidence of portal hypertension (PHT), this analysis focused on differences in sustained virologic response at post-treatment week 12 (SVR12) between 8-week and 12-week G/P treatment groups in patients with PHT, and on differences in safety outcomes between PHT and non-PHT groups.

METHODS

Data were derived from an ad hoc subgroup analysis of the EXPEDITION-8 study for patients receiving 8 weeks of G/P therapy, and pooled patient-level data from nine clinical studies for patients receiving 12 weeks of therapy. Evidence of PHT included at least one of the following at baseline: FibroScan ≥ 20 kPa, platelets < 100 × 109/L, or medical history consistent with PHT. The primary efficacy endpoint was SVR12; adverse events (AEs) consistent with hepatic decompensation were assessed.

RESULTS

PHT was identified in 60.6% (208/343) and 57.1% (224/392) of the 8- and 12-week groups, respectively. For those with PHT, SVR12 was 97.6% (203/208) and 98.7% (221/224) with 8- and 12-week treatment, respectively (intention-to-treat population). For those without PHT, 97.8% (132/135) in the 8-week group and 97.6% (164/168) in the 12-week group achieved SVR12. Eight patients with PHT, and seven without, did not achieve SVR12. Similar rates of AEs were observed in the PHT and non-PHT groups. Three cases of hepatic decompensation in the PHT group, unrelated to G/P according to the investigators, were reported.

CONCLUSION

G/P treatment for 8 or 12 weeks was equally efficacious in HCV patients with features of PHT. Safety outcomes were similar between PHT and non-PHT groups, with G/P treatment well tolerated across groups. NCTS: NCT03089944, NCT02642432, NCT02738138, NCT02243293, NCT02651194, NCT03235349, NCT02707952, NCT02966795, NCT03069365, NCT03219216.

HCV Viral Load Greater Than 1000 IU/ml at Time of Virologic Failure in Direct-Acting Antiviral-Treated Patients

INTRODUCTION

One of the remaining barriers to reaching WHO elimination targets of achieving global hepatitis C (HCV) cure is a lack of an established lower limit of detection (LLOD) to confirm cure post-treatment in near-patient technologies. Determining a LLOD at virologic failure aids in increasing testing feasibility through point-of-care assays in resource-limited settings.

METHODS

We described the level of viremia in 69 patients experiencing virologic failure across 20 clinical trials (ENDURANCE-1, ENDURANCE-2, ENDURANCE-3, ENDURANCE-4, ENDURANCE 5-6, MAGELLAN-1, MAGELLAN-2, EXPEDITION-1, EXPEDITION-2, EXPEDITION-3, EXPEDITION-4, EXPEDITION-5, EXPEDITION-8, SURVEYOR-1, SURVEYOR-2, VOYAGE-1, VOYAGE-2, CERTAIN-1, CERTAIN-2 and APRI). These findings were categorized as on-treatment, post-treatment week (PTW) 4 or PTW12 failures.

RESULTS

The mean HCV RNA level at baseline in the overall population of 5033 patients was 4,193,712 IU/ml ± 5,955,028 (6.2 log10 IU/ml ± 0.8) compared to 9,585,957 IU/ml ± 8,247,669 (6.8 log10 IU/ml ± 0.5) in 69 patients experiencing virologic failure by PTW12. The mean HCV RNA level at the time of virologic failure for all patients was 6,004,980 IU/ml ± 7,077,728 (6.4 log10 IU/ml ± 0.7). Twenty patients had on-treatment virologic failure with a mean HCV RNA level at the time of failure of 9,136,360 IU/ml ± 8,572,113 (6.7 log10 IU/ml ± 0.7), 36 patients had relapsed by PTW4 with a mean HCV RNA level at the time of relapse of 4,131,344 IU/ml ± 5,246,954 (6.3 log10 IU/ml ± 0.6), and 13 patients, who experienced relapse between PTW4 and PTW12, had a mean HCV RNA at relapse of 6,376,003 IU/ml ± 7,758,968 (6.3 log10 IU/ml ± 1.0).

CONCLUSIONS

At PTW12, 100% of virologic failures had an HCV RNA > 3.0 log10 IU/ml. The data are encouraging that with a LLOD of 3.0 log10 IU/ml, a point-of-care test could identify all treatment failures accurately; larger studies, including real-world data, are needed to confirm these findings.