Efficacy and Pharmacokinetics of Glecaprevir and Pibrentasvir With Concurrent Use of Acid-Reducing Agents in Patients With Chronic HCV Infection

SASLT guidelines: Update in treatment of hepatitis C virus infection, 2024

ABSTRACT

Hepatitis C virus (HCV) infection has been a major global health concern, with a significant impact on public health. In recent years, there have been remarkable advancements in our understanding of HCV and the development of novel therapeutic agents. The Saudi Society for the Study of Liver Disease and Transplantation formed a working group to develop HCV practice guidelines in Saudi Arabia. The methodology used to create these guidelines involved a comprehensive review of available evidence, local data, and major international practice guidelines regarding HCV management. This updated guideline encompasses critical aspects of HCV care, including screening and diagnosis, assessing the severity of liver disease, and treatment strategies. The aim of this updated guideline is to assist healthcare providers in the management of HCV in Saudi Arabia. It summarizes the latest local studies on HCV epidemiology, significant changes in virus prevalence, and the importance of universal screening, particularly among high-risk populations. Moreover, it discusses the promising potential for HCV elimination as a public health threat by 2030, driven by effective treatment and comprehensive prevention strategies. This guideline also highlights evolving recommendations for advancing disease management, including the treatment of HCV patients with decompensated cirrhosis, treatment of those who have previously failed treatment with the newer medications, management in the context of liver transplantation and hepatocellular carcinoma, and treatment for special populations.

Antiviral Treatment Failures After Transplantation of Organs From Donors With Hepatitis C Infection: A Report of 4 Cases

The transplantation of organs from donors with hepatitis C virus (HCV) infection into uninfected recipients has expanded the available organ donor pool. With the advancement of direct-acting antivirals (DAAs), high rates of cure among transplant recipients are possible. Although DAAs are highly effective, treatment failure can occur following an appropriate 12-week course of a pan-genotypic regimen. Here we describe 4 kidney transplant recipients of organs from donors with HCV infection (3 with genotype 3, 1 genotype 1a) in whom first-line DAA treatment with either glecaprevir-pibrentasvir or sofosbuvir-velpatasvir was unsuccessful, started 22-35 days after the day of transplantation. All ultimately achieved sustained virologic response with second- or third-line therapy. Post-treatment resistance-associated substitutions were tested and noted to be present in 2 cases. Additionally, antiviral levels were assessed in 2 cases and found to be therapeutic in each. This article explores possible reasons for treatment failure, including medication interactions, bariatric surgery, viral dynamics, and drug resistance.

Evaluation of US Food and Drug Administration Drug Label Recommendations for Coadministration of Antivirals and Acid-Reducing Agents

Coadministration with acid-reducing agents (ARAs), including proton pump inhibitors (PPIs), histamine H2 -receptor antagonists (H2 blockers), and antacids has been demonstrated to reduce antiviral exposure and efficacy. Therefore, it is essential that US Food and Drug Administration (FDA) drug labels include recommendations to manage these drug-drug interactions (DDIs). This investigation analyzed information in FDA drug labels to manage DDIs between ARAs and antivirals approved from 1998 to 2019. To ascertain clinical adoption, we assessed whether FDA label recommendations were incorporated into current antiviral clinical practice guidelines. We identified 82 label recommendations for 43 antiviral approvals. Overall, 56.1% of recommendations were deemed clinically actionable, with the most common actionable management strategies being dose adjustment during coadministration (40.2%) and coadministration not recommended (9.8%). The sources informing DDI recommendations were clinical DDI studies (59.8%) and predictions of altered exposure (40.2%). Antivirals with low aqueous solubility were more likely to have label recommendations and were more commonly investigated using clinical DDI studies (P < 0.01). For recommendations informed by clinical DDI studies, changes in drug exposure were associated with actionable label recommendations (P < 0.01). The frequency of exposure changes in clinical DDI studies was similar across antiviral indications, but exposure changes were numerically higher for antacids (71.4%) relative to PPIs (42.9%) and H2 blockers (28.6%). Of DDI pairs identified within drug labels, 76.8% were included in guidelines, and recommended management strategies were concordant in 90.5% of cases. Our findings demonstrate that current regulatory oversight mostly (but not completely) results in actionable label recommendations to manage DDIs for high-risk antivirals.

An update on drug-drug interactions associated with proton pump inhibitors

INTRODUCTION

Proton pump inhibitors (PPIs) block the gastric H/K-ATPase, therefore inhibiting acid gastric secretion, leading to an increased pH (>4). They account for an extremely high number of prescriptions worldwide. Numerous drug-drug interactions have been described with PPIs, but all the described interactions do not have clinical significance.

AREAS COVERED

This review will discuss the latest updates on drug-drug interactions with PPIs, focusing on the last ten-year publications in the following areas: anti-infective agents, anticancer drugs, antiplatelet agents and anticoagulants, and antidiabetics.

EXPERT OPINION

Although pharmacokinetic interactions of PPIs have been described with many drugs, their clinical relevance remains controversial. However, given the extremely high number of people being treated with PPIs, clinicians should remain vigilant for interactions that may be clinically significant and require dose adjustment or therapeutic monitoring. Interestingly, not all PPIs have the same pharmacokinetic and pharmacodynamic profile, with some having a strong potential to inhibit CYP2C19, such as omeprazole, esomeprazole and lansoprazole, while others, pantoprazole, rabeprazole and dexlansoprazole, are weak CYP2C19 inhibitors. These may be preferred depending on co-prescribed treatments.In addition, new formulations have been developed to prevent some of the gastric pH-dependent drug interactions and should be evaluated in further large-scale prospective comparative studies.

The impact of proton pump inhibitors in liver diseases and the effects on the liver

In this systematic and comprehensive overview, we aimed to evaluate the impact of proton pump inhibitors (PPIs) on chronic liver diseases, especially on cirrhosis. A manual and comprehensive search of the PubMed database was conducted to obtain relevant literatures. PPIs altered the composition and function of the intestinal microflora and might lead to small intestinal bacterial overgrowth and bacterial translocation, which were associated with adverse effects in liver diseases. They might increase the risk of hepatic encephalopathy, spontaneous bacterial peritonitis, infections, and are related to an increased mortality in cirrhosis. PPIs might lead to an increased risk of hepatocellular carcinoma, although the mechanism is unknown, and the results are controversial. PPIs also had an impact on the direct-acting antiviral regimen in patients with chronic hepatitis C. They were associated with an increased risk of liver abscess and increased mortality. Additionally, PPIs might lead to metabolic risk events, such as liver steatosis and weight gain. PPIs are associated with several adverse outcomes in liver diseases. Cautious use of PPIs is recommended and clinicians should be aware of the indications for their use in patients with liver diseases.

Outcomes of short-duration antiviral prophylaxis for hepatitis C positive donor kidney transplants

Trials describing 4- to 12-week courses of direct-acting antiviral drugs (DAAs) to treat hepatitis C virus (HCV) transmission from infected donors to uninfected kidney transplant recipients (D+/R- transplants) may be limited in "real-world" application by costs and delayed access to DAAs. We previously reported HCV transmission of 13% among D+/R- transplants with 2- to 4-day pangenotypic sofosbuvir/velpatasvir (SOF/VEL) perioperative prophylaxis, where one patient with HCV transmission was a nonresponder to first-line full-course DAA. Here, we report new data with a 7-day prophylaxis protocol (N = 50), as well as cumulative treatment and outcome data on all HCV D+/R- transplants (N = 102). Overall, nine patients (9/102; 9%; 95% CI: 5%-16%) developed HCV transmission, with a significant decline noted in the 7-day group (2/50; 4%; 95% CI: 0%-13%) compared with 2- to 4-day prophylaxis (7/52; 13%; 95% CI: 5%-25%). All patients with HCV transmission achieved sustained virologic response post full-course therapy (including one nonresponder from initial trial). A 1:1 matched analysis (N = 102) with contemporary HCV D-/R- transplants (controls) showed that although the pretransplant wait time was significantly shorter for D+/R- compared with D-/R- (mean: 1.8 vs. 4.4 years; p < .001), there were no differences in infections, rejection, development of de novo donor-specific antibody, or transplant outcomes up to 6 months of transplant.

Development of Acid-Neutralization and in Vitro Dissolution to Evaluate the Overall Quality of Compound Aluminum Hydroxide Tablets

Background:

Compound aluminum hydroxide tablets (CAHTs) are widely used in the Chinese domestic market, and strict quality control is required to ensure their clinical efficacy.

Purpose:

In this study, we established a comprehensive strategy of acid-neutralization, in vitro dissolution and an assay of magnesium trisilicate to evaluate the overall quality and monitor the consistency of CAHTs.

Methods:

The acid-neutralization profiles of 38 batches of CAHTs were generated using the dissolution and release method III (the cup method, the Chinese pharmacopeia) combined with potentiometric titration. To directly reflect the disintegration and release process of the preparation, we optimized the sample pretreatment method by omitting the grinding step to determine the profiles of complete tablets. In addition, in vitro dissolution was conducted in the hydrochloric acid medium at pH 1.0 by using the assay of magnesium trisilicate through a validated approach of flame atomic absorption spectrophotometry (FAAS) to evaluate the similarity of the dissolution profiles.

Results:

Acid-neutralization tests showed that the quality of the samples from manufacturers B and F was poor. In vitro dissolution experiments showed that the samples from manufacturer A had the highest similarity with the reference preparation, which indicated their good quality consistency. Besides, the optimized acid-neutralization method had the advantage of simple operation and enabled direct characterization of pharmacodynamics in the quality consistency evaluation of antacids.

Conclusion:

A successful synthetic evaluation strategy was established to assess the overall quality of CAHTs, which demonstrated that the improvement in the quality of this formulation is imperative.

Impact of gastrointestinal tract variability on oral drug absorption and pharmacokinetics: An UNGAP review

The absorption of oral drugs is frequently plagued by significant variability with potentially serious therapeutic consequences. The source of variability can be traced back to interindividual variability in physiology, differences in special populations (age- and disease-dependent), drug and formulation properties, or food-drug interactions. Clinical evidence for the impact of some of these factors on drug pharmacokinetic variability is mounting: e.g. gastric pH and emptying time, small intestinal fluid properties, differences in pediatrics and the elderly, and surgical changes in gastrointestinal anatomy. However, the link of colonic factors variability (transit time, fluid composition, microbiome), sex differences (male vs. female) and gut-related diseases (chronic constipation, anorexia and cachexia) to drug absorption variability has not been firmly established yet. At the same time, a way to decrease oral drug pharmacokinetic variability is provided by the pharmaceutical industry: clinical evidence suggests that formulation approaches employed during drug development can decrease the variability in oral exposure. This review outlines the main drivers of oral drug exposure variability and potential approaches to overcome them, while highlighting existing knowledge gaps and guiding future studies in this area.

Efficacy and Safety of Glecaprevir/Pibrentasvir in Patients with Chronic HCV Infection

Hepatitis C virus (HCV) infection is a major cause of end-stage liver disease, including decompensated cirrhosis and hepatocellular carcinoma. Over 95% of patients with HCV infection have achieved sustained virologic response at 12 weeks under the treatment of several pan-genotypic regimens approved for patients with HCV infection. The glecaprevir/pibrentasvir (G/P) regimen has some features that distinguish it from others and is the only 8-week regimen approved for treatment-naive patients and patients experienced in regimens containing (peg)interferon, ribavirin, and/or sofosbuvir, without an HCV NS3/4A protease inhibitor or NS5A inhibitor (except those with genotype 3). This review aims to summarize the efficacy and safety of G/P in HCV-infected patients from clinic trials and real-world studies, including those who have historically been considered difficult to cure.

Direct antiviral agents for hepatitis C and drug interaction risk: A retrospective cohort study with real and simulated data on medication interaction, prevalence of comorbidities and comedications

Introduction and aim

Comorbidities and comedication are common in patients with hepatitis C, which could result in a risk of drug-drug interaction. The objective of this study was to evaluate the prevalence of comorbidities, comedication and drug-drug interactions involving direct-acting antivirals in this population.

Methods

Comorbidities and comedications were evaluated in a retrospective cohort of hepatitis C patients. Drug-drug interactions were estimated in real life and with simulated data on comedications following drug regimens: telaprevir; elbasvir/grazoprevir, ombitasvir/paritaprevir/r/ritonavir (2D regimen), and sofosbuvir/simeprevir, sofosbuvir/daclatasvir, sofosbuvir/ledipasvir; 2D/dasabuvir (3D regimen); glecaprevir/pibrentasvir and sofosbuvir/velpatasvir/voxilaprevir. The interactions were evaluated according to the University of Liverpool database. Statistical analysis was performed by SPSS^® 18.0.

Results

Data from 1433 patients with hepatitis C were evaluated. The mean patient age was 51.7 years (SD ± 10.7), and 50.6% were female. Direct-acting antivirals were prescribed for 345 (24.1%) patients, and a sustained virological response occurred in 264 (76.5%). The main comorbidities were systemic arterial hypertension [436 (30.4%)], diabetes mellitus [352 (24.6%)] and depression [130 (9.1%)]. The mean number of comorbidities was 1.52 (median [IQR] of 1.00 [1.00–2.00]). The mean number of comedications was 3.16 (median [IQR] of 3.00 [1.00–5.00]). A total of 12916 drug-drug interactions were found, of which 1.859 (14.4%) were high risk, with a mean of 1.29 ± 3.13 per patient. The 3D regimen, as well as glecaprevir/pibrentasvir and sofosbuvir/velpatasvir/voxilaprevir, presented the highest drug-drug interaction indexes.

Conclusion

Comorbidities and comedications are common in patients with hepatitis C, as are drug-drug interactions. Even when second generation drugs are used, the occurrence of drug-drug interactions still presents a significant risk.

Influence of drug-drug interactions on effectiveness and safety of direct-acting antivirals against hepatitis C virus

OBJECTIVES

Direct-acting antivirals are the recommended treatment for hepatitis C-infected patients. Drug-drug interactions with concomitant treatments can cause lack of effectiveness and/or safety. The objective of this study is to characterise drug-drug interactions of direct-acting antivirals and to analyse their influence both on the effectiveness of antiviral treatment and on the overall safety of pharmacological treatment in hepatitis C-infected patients.

METHODS

Observational and prospective cohort study for 3 years in the pharmaceutical care outpatient consultation of a general hospital, undertaking detection, evaluation and management of drug-drug interactions by clinical pharmacists and physicians. The main outcome measures were sustained virologic response at week 12 for effectiveness and serious drug-related adverse events for safety. Multivariate statistical analysis applied to: (a) patient basal characteristics related to presence of drug-drug interactions; (b) previous antiviral treatments, viral genotype, cirrhosis, decompensations and presence of drug-drug interactions related to the effectiveness of direct-acting antivirals.

RESULTS

Of a total of 1092 patients, the majority of them were men, around 60 years old and HCV-genotype 1 mono-infected, with a high basal viral load, naive to antiviral treatment, treated with ledipasvir/sofosbuvir and without cirrhosis. 24.5% had drug-drug interactions. Proton pump inhibitors were the concomitant drugs that caused the most drug-drug interactions. Age ≥65 years and direct-acting antivirals based on protease inhibitors were independently related to the presence of drug-drug interactions (p≤0.012). All (100%) of the therapeutic recommendations based on detected drug-drug interactions were implemented; 97.7% of patients with interactions versus 99.0% without them reached sustained virologic failure (p=0.109). The serious adverse events rates were 1.5% and 1.3% in patients with and without drug-drug interactions, respectively (p=0.841).

CONCLUSIONS

Drug-drug interactions are frequent among hepatitis C-infected patients receiving treatment with direct-acting antivirals. However, the collaboration between physicians and clinical pharmacists makes it possible to detect, evaluate, avoid or clinically manage these drug-drug interactions, in order to maintain whole treatment therapeutic safety and the effectiveness of direct-acting antivirals.

Review of Clinically Relevant Drug Interactions with Next Generation Hepatitis C Direct-acting Antiviral Agents

In this review, we examine the pharmacokinetics and clinically relevant drug interactions of the newer generation direct-acting antivirals (DAAs) for the treatment of chronic hepatitis C, specifically sofosbuvir/velpatasvir (Epclusa®), sofosbuvir/velpatasvir/voxilaprevir (Vosevi®), glecaprevir/pibrentasvir (Maviret®), and elbasvir/grazoprevir (Zepatier®). We searched MEDLINE (1948-January 2020), Embase (1964-January 2020), Google, and GoogleScholar using the terms pharmacokinetics, drug interaction, drug metabolism, sofosbuvir, velpatasvir, Epclusa, voxilaprevir, Vosevi, glecaprevir, pibrentasvir, Maviret, elbasvir, grazoprevir, and Zepatier, from inception to January 13, 2020. The search was limited to randomized controlled trials, in vitro studies, prospective and retrospective human studies, drug monographs, abstracts, and conference proceedings. All relevant published literature on pharmacokinetic and pharmacodynamic interactions involving DAAs were reviewed and the data extracted. Numerous clinically relevant drug-drug interactions (DDIs) were identified with the newer generation DAAs and commonly prescribed drugs. NS3/4A protease inhibitors are more likely to be involved in DDIs, followed by NS5A inhibitors and NS5B polymerase inhibitor. The majority of clinically relevant DDIs are predictable, according to known pharmacokinetic, pharmacodynamics, and physicochemical properties of DAAs; however, in select cases, unpredictable DDIs do occur. As expected, many drug interactions exist between newer generation DAAs and commonly prescribed medications. While the majority of clinically relevant interactions are predictable, many require therapeutic dose adjustment or careful selection of non-interacting drugs. In select cases, severe and unpredictable drug interactions can occur. Clinicians should consult hepatitis C virus pharmacotherapy experts and tertiary drug interaction resources when initiating DAA therapy in patients taking other medications.

PK/PD and antiviral activity of anti-HCV therapy: is there still a role in the choice of treatment?

Introduction: Despite the high rate of response, the treatment of special populations, the management of patients with previous failure to direct-acting antiviral (DAA) regimens, and the development of drug resistance are still a challenge. Moreover, the FDA suggested stopping research on new DAA because of the high efficacy of those already available.Areas covered: Understanding pharmacokinetic/pharmacodynamic parameters could be a simple and effective way to improve the management of anti-hepatitis C virus (HCV) treatment. The aim of this review is to provide an overview of this aspect in order to offer a new insight into treatment choice.Expert opinion: Clinicians should offer an adequate strategy for HCV treatment taking into consideration patient-related factors and by improving their knowledge of the antiviral activity and pharmaceutical 'forgiveness' of each DAA.

Review article: direct-acting antivirals for the treatment of HCV during pregnancy and lactation - implications for maternal dosing, foetal exposure, and safety for mother and child

BACKGROUND

With the global efforts to eradicate hepatitis C virus (HCV), treatment during pregnancy is becoming a priority for research as this, and maternal cure should reduce vertical transmission. However, as information on the efficacy and safety of direct-acting antivirals (DAAs) in pregnancy is generally lacking, treatment of HCV infection during pregnancy is not currently recommended.

AIM

To provide an overview of current knowledge regarding maternal exposure, placental handling and safety of DAAs during pregnancy and lactation METHODS: A literature search was performed focusing on the effect of pregnancy on maternal exposure to DAAs, the placental handling of DAAs, the safety of DAAs for mother and child during pregnancy and the safety of DAAs during lactation.

RESULTS

Exposure to all DAAs studied is likely to be altered during pregnancy, mostly related to pregnancy-induced effects on drug absorption and metabolism. Although animal studies show that most DAAs are reported to cross the placenta and transfer into breast milk, most DAA combinations show a favourable safety profile. Because of the rapid viral decline after treatment initiation, and to avoid the critical period of organogenesis, treatment may be started at the end of the second trimester or early third trimester.

CONCLUSIONS

Treatment of HCV infection during pregnancy is realistic, as DAAs are highly effective and treatment duration is relatively short. There is an urgent need to study DAAs during pregnancy and lactation to contribute to the goal of HCV elimination.

Treatment of Chronic Hepatitis C: Efficacy, Side Effects and Complications

Background

Chronic hepatitis C virus (HCV) infection can lead to liver cirrhosis and its complications. Viral eradication is essential to prevent disease progression and reduces liver-related mortality and morbidity. Since the availability of direct-acting antivirals (DAA), HCV treatment has changed significantly. Current treatment strategies for different groups of patients as well as potential risks and caveats will be discussed in this review.

Summary

Interferon-free (IFN-free) treatment not only shortens treatment duration, but also achieves high rates of viral clearance and is overall well tolerated. Genotype-restricted but also pangenotypic combinations are available. Usually two DAA of different drug classes are combined. For the majority of the patients, treatment duration ranges from 8 to 12 weeks. Liver and kidney function as well as prior treatment experience and potential drug-drug interactions influence substance choices and treatment duration. However, modern IFN-free treatment is not only safer, but also overall far more simplified and effective. Global HCV eradication might be an ambitious but not completely unrealistic goal to pursue.

Key Messages

IFN-free antiviral treatment is safe and well tolerated. Patients can be treated almost independently of liver function or concomitant disease. Viral eradication is associated with reduced morbidity and mortality and better quality of life.