Discordance Between Child-Pugh and National Cancer Institute Classifications for Hepatic Dysfunction: Implications on Dosing Recommendations for Oncology Compounds

Effects of Hepatic or Renal Impairment on Pharmacokinetics of Fruquintinib

Fruquintinib (FRUZAQLATM) is a highly selective tyrosine kinase inhibitor of all three vascular endothelial growth factor receptors (-1, -2, and -3). Two Phase 1, open-label, single-dose studies investigated the impact of hepatic or renal impairment on the pharmacokinetics and tolerability of fruquintinib. Participants with moderate renal impairment (creatinine clearance [CrCl] 30-59 mL/min; eight participants) and matched healthy controls (eight participants for each study) received fruquintinib 5 mg. Participants with moderate hepatic impairment (Child-Pugh B; eight participants) and severe renal impairment (CrCl 15-29 mL/min; eight participants) received fruquintinib 2 mg. Pharmacokinetic samples were collected over 240 h. Fruquintinib pharmacokinetics were similar between participants with moderate hepatic impairment and healthy controls; geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for maximum plasma concentration (Cmax), area under the plasma concentration-time curve from 0 to time of last measurable concentration (AUC0-t), and AUC from 0 to infinity (AUC0-inf) were 1.04 (0.87-1.24), 0.89 (0.64-1.23), and 0.91 (0.66-1.26), respectively. Fruquintinib pharmacokinetics were similar between participants with severe or moderate renal impairment and healthy controls. Compared with healthy controls, the respective GMRs (90% CIs) for Cmax, AUC0-t, and AUC0-inf for participants with severe renal impairment were 0.89 (0.78-1.03), 0.97 (0.83-1.14), and 1.01 (0.85-1.19), and for participants with moderate renal impairment were 0.95 (0.78-1.15), 1.06 (0.89-1.26), and 1.07 (0.89-1.28). Fruquintinib was generally well tolerated. These results support fruquintinib use without dose adjustment (5 mg daily, 3 weeks on, and 1 week off) in patients with moderate hepatic impairment or moderate to severe renal impairment.

Palbociclib Is Safe for Breast Cancer Patients With Mild Hepatic Impairment: A Multicenter Retrospective Study Using Real-World Data

The liver is crucial for metabolizing the anticancer drug palbociclib, but limited information is available on the impact of hepatic impairment on its toxicity and efficacy, with no real-world data available. This study aims to evaluate how hepatic impairment affects hematological toxicity and progression-free survival (PFS) of palbociclib in advanced hormone receptor-positive/human epidermal growth factor receptor 2-negative breast cancer, using the National Cancer Institute scoring system, in a large real-world dataset. This multicenter retrospective observational study included female patients treated with palbociclib between August 2017 and February 2024. Regression analysis was used to compare the risk of developing grade 3/4 hematological toxicity and PFS between patients with normal and mild impaired liver function. In total, 478 female patients were included. Patients with mild hepatic impairment (n = 205) did not have an increased risk of developing grade 3/4 neutropenia compared with patients with normal hepatic function (n = 273) (hazard ratio (HR) = 1.11; 95% CI 0.83-1.47). In addition, the PFS was not significantly different between both groups (HR = 1.15; 95% CI 0.93-1.42). In real-world settings, patients with mild hepatic impairment do not have a higher risk of developing palbociclib-induced neutropenia or disease progression than patients with normal hepatic function. These findings can guide clinicians when treating breast cancer patients with mild hepatic impairment.

Population pharmacokinetic modeling of asciminib in support of exposure-response and ethnic sensitivity analyses in patients with chronic myeloid leukemia

BACKGROUND

The original population pharmacokinetics (popPK) model for asciminib in patients with chronic myeloid leukemia in chronic phase (CML-CP) was refined to address drug development needs in support of drug submission, namely, attainment of target drug exposure in specific patient populations, populating individual daily exposures for exposure-response analyses of key efficacy and safety endpoints, confirmation of comparability in exposure between 40 mg b.i.d. and 80 mg q.d., and assessment of ethnic insensitivity.

METHODS

Participants from two organ dysfunction studies, patients with CML in blast and acute phases and acute lymphoblastic leukemia and patients from a phase III efficacy study in newly diagnosed Ph + CML-CP, and data from a dedicated phase II study in the Chinese patients previously treated with at least two prior tyrosine kinase inhibitors, and a phase IIIb study comparing two dose regimens of asciminib (40 mg b.i.d. and 80 mg q.d.) were included in the revised popPK model. Covariates evaluated were line of therapy, baseline renal and hepatic functions, Chinese or Japanese ethnicity.

RESULTS

The apparent clearance and steady-state volume of distribution of asciminib were 6.84 L/h and 110 L, respectively, for a typical individual of 70 kg weight and 90 mL/min absolute glomerular filtration rate. Both the 40 mg b.i.d. and 80 mg q.d. resulted in a steady-state daily AUC of 12,600 ng.h/mL, and there was no difference between lines of therapy. Effects of renal or hepatic impairment on clearance were not clinically relevant. Chinese and Japanese exhibited similar PK as that of the global population.

CONCLUSIONS

The 40 mg b.i.d. and 80 mg q.d. regimens are comparable in their daily exposure, supporting the use of the two dosing regimens in newly diagnosed and previously treated CML-CP patients. The PK of asciminib is insensitive to ethnic differences and no dose adjustment is required for severe renal and hepatic impaired patients.

Impaired liver function: effect on paclitaxel toxicity, dose modifications and overall survival

BACKGROUND

The anticancer drug paclitaxel is primarily metabolized in the liver. Previous studies have indicated a correlation between impaired liver function and paclitaxel toxicity, which may indicate dose reduction. Since the evidence is limited, the aim of this study was to investigate the effect of impaired liver function on the hematological toxicity of paclitaxel, dose modifications and overall survival (OS).

METHODS

For this single-center retrospective observational study, patients treated with paclitaxel for breast, esophageal and ovarian cancer at the University Medical Centre Utrecht between 2011 and 2022 were identified from the Utrecht Patient Oriented Database (UPOD). Based on regression analysis, the risk of developing Grade 3/4 hematological toxicity was compared between patients with normal and impaired (based on the NCI criteria for bilirubin and ASAT (aspartate aminotransferase) concentrations) liver function. Additionally, differences in the occurrence of toxicity-related dose modifications and OS were evaluated between the two groups.

RESULTS

A total of 569 patients were included. Breast cancer patients who were receiving advanced treatment and had mildly impaired liver function (ASAT ≤ 2x ULN, bilirubin ≤ ULN) had an increased risk of developing grade 3/4 neutropenia (HR = 4.39, 95% CI 1.20-16.02; p = 0.03). In addition, patients with impaired liver function treated according to the advanced ovarian cancer regimen had an increased risk of developing grade 3/4 leukopenia (HR = 12.64, 95% CI 2.12-75.22, p = 0.01) and dose modification (treatment discontinuation) (HR = 3.91, 95% CI 1.74-8.79, p < 0.01). Impaired liver function was also associated with decreased OS in inoperable esophageal and advanced ovarian cancer patients (HR = 7.65, 95% CI 2.54-23.1, p < 0.01 and HR = 2.98, 95% CI 1.36-6.54, p < 0.01, respectively). The risk of developing grade 3/4 hematological toxicity during lower-dose paclitaxel treatment protocols was not significantly different in patients with impaired liver function.

CONCLUSIONS

This study revealed that patients with impaired liver function treated with paclitaxel for breast and ovarian cancer in an advanced setting are at greater risk of developing hematological toxicity than patients with normal liver function at the start of therapy. Furthermore, in patients with ovarian (advanced) or inoperable esophageal cancer, impaired liver function is associated with decreased OS. Within these groups of patients, it is important to weigh the risk of upfront paclitaxel dose modifications versus an adaptive strategy.

Pharmacokinetic Prediction of Immediate- and Extended-Release Tablets for Patients with Liver Disease Using Whole Body Physiologically-Based Pharmacokinetic Modeling for the Antipsychotic Drug Quetiapine

Although quetiapine metabolism occurs extensively in the liver and careful dosing is recommended in patients with liver disease, there has been a paucity of pharmacometric studies to adjust the clinical dose of quetiapine according to liver-disease severity. This study aimed to establish a whole-body, physiologically-based pharmacokinetic (WB-PBPK) model to explain interindividual variability in quetiapine PK and quantitatively predict PK in patients with liver disease. The developed WB-PBPK model well described the PK characteristics of different quetiapine regimens in healthy populations. The PK predictions could also be applied to patients with schizophrenia (without significant differences from healthy subjects). For the same total dose of quetiapine, both immediate-release (IR) and extended-release (ER) tablets showed significantly increased exposure and decreased clearance in patients with liver disease compared to healthy subjects. The model showed that steady-state plasma quetiapine concentrations exceeded the usual therapeutic range after multiple doses of IR tablets 250 mg three times daily or ER tablets 800 mg once daily in patients with liver disease. Therefore, the doses of quetiapine IR or ER tablets could be reduced by 0.10-0.50 times depending on liver-disease severity, so that mean steady-state plasma concentrations could be positioned near the therapeutic range. WB-PBPK modeling for quetiapine enabled quantitative prediction of PK according to IR or ER formulation and liver-disease severity. The results of this study provide useful data for improving the therapeutic use of quetiapine by enabling dose selection based on formulation and liver-disease severity.

Disposition of Oral Nalbuphine and Its Metabolites in Healthy Subjects and Subjects with Hepatic Impairment: Preliminary Modeling Results Using a Continuous Intestinal Absorption Model with Enterohepatic Recirculation

Nalbuphine (NAL) is a mixed κ-agonist/μ-antagonist opioid with extensive first-pass metabolism. A phase 1 open-label study was conducted to characterize the pharmacokinetics (PKs) of NAL and select metabolites following single oral doses of NAL extended-release tablets in subjects with mild, moderate, and severe hepatic impairment (Child-Pugh A, B, and C, respectively) compared to healthy matched subjects. NAL exposures were similar for subjects with mild hepatic impairment as compared to healthy subjects and nearly three-fold and eight-fold higher in subjects with moderate and severe hepatic impairment, respectively. Datasets obtained for healthy, moderate, and severe hepatic impaired groups were modeled with a mechanistic model that incorporated NAL hepatic metabolism and enterohepatic recycling of NAL and its glucuronidated metabolites. The mechanistic model includes a continuous intestinal absorption model linked to semi-physiological liver-gallbladder-compartmental PK models based on partial differential equations (termed the PDE-EHR model). In vitro studies indicated that cytochromes P450 CYP2C9 and CYP2C19 are the major CYPs involved in NAL oxidation, with glucuronidation mainly catalyzed by UGT1A8 and UGT2B7 isozymes. Complex formation and elimination kinetics of NAL and four main metabolites was well predicted by PDE-EHR. The model is expected to improve predictions of drug interactions and complex drug disposition.

Effect of Hepatic Impairment on Trilaciclib Pharmacokinetics

Trilaciclib is a first-in-class, intravenous cyclin-dependent kinase 4 and 6 inhibitor approved for reducing the incidence of chemotherapy-induced myelosuppression in adult patients with extensive-stage small cell lung cancer receiving a platinum/etoposide-containing or topotecan-containing regimen. No dose adjustment is recommended for participants with mild hepatic impairment (HI) based on previous population pharmacokinetic (PK) analysis. This open-label, parallel-group study examined the impact of moderate and severe HI on the PK of trilaciclib. The study employed a reduced study design. Participants with moderate (Child-Pugh B, n = 8) and severe (Child-Pugh C, n = 5) HI and matched healthy controls (n = 11) received a single intravenous dose of trilaciclib 100 mg/m2. The unbound fraction of trilaciclib was comparable between the HI groups and the matched healthy control group. The unbound trilaciclib extent of exposure (i.e., area under the concentration-time curve) in participants with moderate and severe HI was ∼40% and ∼60% higher, respectively, compared with healthy matched controls based on Child-Pugh classification. Ad hoc analysis using National Cancer Institute classification showed similar results. The US Food and Drug Administration-approved trilaciclib dose of 240 mg/m2 should be reduced by ∼30%, to 170 mg/m2, for patients with moderate or severe HI.

The effect of liver dysfunction on the pharmacokinetic disposition of belinostat and its five metabolites in patients with advanced cancers

Belinostat was approved in 2014 for the treatment of relapsed or refractory peripheral T-cell lymphoma, however, there was insufficient data to recommend a dose in patients with moderate to severe hepatic impairment. The purpose of this analysis was to characterize the pharmacokinetic disposition of belinostat and its five metabolites in patients with advanced cancers and varying degrees of liver dysfunction. A population pharmacokinetic model was therefore developed to describe the parent-metabolite system. The final model was then implemented to assess the effect of liver impairment on each metabolic pathway of belinostat. It was determined that significant pharmacokinetic differences could only be demonstrated in patients with severe hepatic impairment. The final model estimated a 35%-47% reduction in metabolic clearance attributed to UGT1A1/2B7 glucuronidation, CYP2A6/3A4/2C9 metabolism, and β-oxidation. These hepatic impairment effects reduced between-subject variability by only 5%-8% for their respective parameter, with a large amount of remaining unexplained variability. With further validation, this model can be leveraged to assess the need for dose adjustments in this patient population.

Hepatic Dysfunction Quantified by HepQuant DuO Outperforms Child-Pugh Classification in Predicting the Pharmacokinetics of Ampreloxetine

HepQuant tests quantify liver function from clearance of deuterium- and 13C-labeled cholates administered either intravenously and orally (SHUNT) or orally (DuO). Hepatic impairment studies have relied on clinical or laboratory criteria like Child-Pugh classification to categorize the degree of hepatic dysfunction. We compared HepQuant tests with Child-Pugh classification in predicting the pharmacokinetics of ampreloxetine. Twenty-one subjects with hepatic impairment (8 Child-Pugh A, 7 Child-Pugh B, and 6 Child-Pugh C), and 10 age- and sex-matched controls were studied. The pharmacokinetics of ampreloxetine were measured after oral administration of a single dose of 10 mg. Disease severity index (DSI), portal-systemic shunting (SHUNT%), hepatic reserve, and hepatic filtration rates (HFRs) were measured from serum samples obtained after intravenous administration of [24-13C]-cholate and oral administration of [2,2,4,4-2H]cholate. Ampreloxetine plasma exposure (AUC0-inf) was similar to controls in Child-Pugh A, increased 1.7-fold in subjects with Child-Pugh B, and 2.5-fold in subjects with Child-Pugh C and correlated with both Child-Pugh score and HepQuant parameters. The variability observed in ampreloxetine exposure (AUC0-inf) in subjects with moderate (Child-Pugh B) and severe hepatic impairment (Child-Pugh C) was explained by HepQuant parameters. Multivariable regression models demonstrated that DSI, SHUNT%, and Hepatic Reserve from SHUNT and DuO were superior predictors of ampreloxetine exposure (AUC0-inf) compared to Child-Pugh score. HepQuant DSI, SHUNT%, and hepatic reserve were more useful predictors of drug exposure than Child-Pugh class for ampreloxetine and thus may better optimize dose recommendations in patients with liver disease. The simple-to-administer, oral-only DuO version of the HepQuant test could enhance clinical utility.

Exploring the Impact of Hepatic Impairment on Pralsetinib Pharmacokinetics

Pralsetinib is a kinase inhibitor indicated for the treatment of metastatic rearranged during transfection (RET) fusion-positive non-small cell lung cancer. Pralsetinib is primarily eliminated by the liver and hence hepatic impairment (HI) is likely alter its pharmacokinetics (PK). Mild HI has been shown to have minimal impact on the PK of pralsetinib. This hepatic impairment study aimed to determine the pralsetinib PK, safety and tolerability in subjects with moderate and severe HI, as defined by the Child-Pugh and National Cancer Institute Organ Dysfunction Working Group (NCI-ODWG) classification systems, in comparison to subjects with normal hepatic function. Based on the Child-Pugh classification, subjects with moderate and severe HI had similar systemic exposure (area under the plasma concentration time curve from time 0 to infinity [AUC0-∞]) to pralsetinib, with AUC0-∞ geometric mean ratios (GMR) of 1.12 and 0.858, respectively, compared to subjects with normal hepatic function. Results based on the NCI-ODWG classification criteria were comparable; the AUC0-∞ GMR were 1.22 and 0.858, respectively, for subjects with moderate and severe HI per NCI-ODWG versus those with normal hepatic function. These results suggested that moderate and severe hepatic impairment did not have a meaningful impact on the exposure to pralsetinib, thus not warranting a dose adjustment in this population.

Therapeutic Drug Monitoring of Voriconazole in Patients with End-Stage Liver Disease

BACKGROUND

This study aimed to identify the factors that influence voriconazole (VCZ) plasma concentrations and optimize the doses of VCZ in patients with end-stage liver disease (ESLD).

METHODS

Patients with ESLD who received a VCZ maintenance dose of 100 mg twice daily (group A, n = 57) or the VCZ maintenance dose of 50 mg twice daily (group B, n = 37), orally or intravenously, were enrolled in this study. Trough plasma concentrations (Cmin) of VCZ between 1 and 5 mg/L were considered within the therapeutic target range.

RESULTS

The VCZ Cmin was determined in 94 patients with ESLD. The VCZ Cmin of patients in group A was remarkably higher than those in group B (4.85 ± 2.53 mg/L vs 2.75 ± 1.40 mg/L; P < 0.001). Compared with group A, fewer patients in group B had VCZ Cmin outside the therapeutic target (23/57 vs. 6/37, P = 0.021). Univariate and multivariate analyses suggested that both body weight and Model for End-Stage Liver Disease scores were closely associated with the VCZ Cmin in group B.

CONCLUSIONS

These data indicate that dose optimization based on body weight and Model for End-Stage Liver Disease scores is required to strike an efficacy-safety balance during VCZ treatment in patients with ESLD.

Effect of changes in metabolic enzymes and transporters on drug metabolism in the context of liver disease: Impact on pharmacokinetics and drug-drug interactions

Changes in the pharmacokinetic and resulting pharmacodynamic properties of drugs are common in many chronic liver diseases, leading to adverse effects, drug interactions and increased risk of over- or underdosing of medications. Structural and functional hepatic impairment can have major effects on drug metabolism and transport. This review summarizes research on the functional changes in phase I and II metabolic enzymes and in transport proteins in patients with metabolic diseases such as type 2 diabetes, metabolic dysfunction-associated steatotic liver disease, metabolic dysfunction-associated steatohepatitis and cirrhosis, providing a clinical perspective on how these changes affect drug uptake and metabolism. Generally, a decrease in expression and/or activity of many enzymes of the cytochrome P450 family (e.g. CYP2E1 and CYP3A4), and of influx and efflux transporters (e.g. organic anion-transporting polypeptide [OATP]1B1, OATP2B1, OAT2 and bile salt export pump), has been recently documented in patients with liver disease. Decreased enzyme levels often correlate with increased severity of chronic liver disease. In subjects with hepatic impairment, there is potential for strong alterations of drug pharmacokinetics due to reduced absorption, increased volume of distribution, metabolism and extraction. Due to the altered pharmacokinetics, specific drug-drug interactions are also a potential issue to consider in patients with liver disease. Given the huge burden of liver disease in western societies, there is a need to improve awareness among all healthcare professionals and patients with liver disease to ensure appropriate drug prescriptions.

Incorporation and Performance Verification of Hepatic Portal Blood Flow Shunting in Minimal and Full PBPK Models of Liver Cirrhosis

Patho-physiological changes in liver cirrhosis create portacaval shunts that allow blood flow to bypass the hepatic portal vein into the systemic circulation affecting drug pharmacokinetics (PKs). The objectives of this work were to implement a physiologically-based pharmacokinetic (PBPK) framework describing shunted blood flows in virtual patients with differing degrees of liver cirrhosis; and to assess the minimal and full PBPK model's performance using drugs with intermediate to high hepatic extraction. Single dose concentration-time profiles and PK parameters for oral ibrutinib, midazolam, propranolol, and buspirone were simulated in healthy volunteers (HVs) and subjects with cirrhosis (Child-Pugh severity score (CP-A, CP-B, or CP-C)). Model performance was verified by comparing predicted to observed fold-changes in PK parameters between HVs and cirrhotic subjects. The verified model was used to simulate the PK changes for simvastatin in patients with cirrhosis. The predicted area under the curve ratios (AUCCirr :AUCHV ) for ibrutinib were 3.38, 6.87, and 11.46 using the minimal PBPK model with shunt and 1.61, 2.58, and 4.33 without the shunt, these compared with observed values of 4.33, 8.14, and 9.04, respectively. For ibrutinib, propranolol, and buspirone, including a shunt in the PBPK model improved the prediction of the AUCCirr :AUCHV and maximum plasma concentration ratios (CmaxCirr :CmaxHV ). For midazolam, an intermediate extraction drug, the differences were less clear. Simulated simvastatin dose adjustments in cirrhosis suggested that 20 mg in CP-A and 10 mg in CP-B could be used clinically. A mechanistic model-informed understanding of the anatomic and pathophysiology of cirrhosis will facilitate improved dose prediction and adjustment in this vulnerable population.

Pharmacokinetic considerations for angiogenesis inhibitors used to treat hepatocellular carcinoma: an overview

INTRODUCTION

Hepatocellular carcinoma (HCC) is the fifth malignancy in terms of frequency and the fourth malignancy in terms of cancer-related death worldwide. Systemic therapy of advanced HCC has probably gone through the greatest wave of change in the last decade, with the introduction of several anti-angiogenic drugs and immune checkpoint inhibitors, able to significantly improve patients' prognosis.

AREAS COVERED

In this review, we summarize the pharmacokinetic characteristic of the antiangiogenic drugs currently approved for the treatment of HCC, from oral tyrosine kinase inhibitors (sorafenib, lenvatinib, regorafenib and cabozantinib) to monoclonal antibodies (bevacizumab and ramucirumab), focusing on the main aspects that differ among compounds from the same class, on factors that can exert an influence on pharmacokinetic parameters and the main issues that could limit their clinical use.

EXPERT OPINION

Anti-angiogenic drugs have different profiles in terms of bioavailability, metabolism, elimination and interindividual variability in their pharmacokinetics and effectiveness. More studies should be developed to address the intrinsic and extrinsic factors influencing pharmacokinetics parameters to improve the individual therapeutic response and, furthermore, to evaluate the benefit and the harm of systemic therapy for advanced HCC in selected patients with liver impairment.

Design and conduct considerations for studies in patients with hepatic impairment

Despite the liver being the primary site for clearance of xenobiotics utilizing a myriad of mechanisms ranging from cytochrome P450 enzyme pathways, glucuronidation, and biliary excretion, there is a dearth of information available as to how the severity of hepatic impairment (HI) can alter drug absorption and disposition (i.e., pharmacokinetics [PK]) as well as their efficacy and safety or pharmacodynamics (PD). In general, regulatory agencies recommend conducting PK studies in subjects with HI when hepatic metabolism/excretion accounts for more than 20% of drug elimination or if the drug has a narrow therapeutic range. In this tutorial, we provide an overview of the global regulatory landscape, clinical measures for hepatic function assessment, methods to stage HI severity, and consequently the impact on labeling. In addition, we provide an in-depth practical guidance for designing and conducting clinical trials for patients with HI and on the application of modeling and simulation strategies in lieu of dedicated trials for dosing recommendations in patients with HI.

Associations Between Endoscopic Primary Prophylaxis and Rebleeding in Liver Cirrhosis Patients with Esophagogastric Variceal Bleeding

Aim

To identify the association between endoscopic primary prophylaxis and the risk of rebleeding in patients with liver cirrhosis receiving endoscopic therapy.

Methods

This cohort study involved in 944 liver cirrhosis patients with esophagogastric variceal bleeding (EGVB) receiving endoscopic therapy. All participants were divided into two groups: rebleeding group (n = 425) and non-rebleeding group (n = 519) according to the occurrence of rebleeding in patients. Rebleeding indicated any bleeding after endoscopic therapy for the first bleeding of esophagogastric varices in liver cirrhosis patients. Univariate and multivariate logistic analyses were employed to identify the association between endoscopic primary prophylaxis and rebleeding in patients with liver cirrhosis after endoscopic therapy.

Results

In total, 425 patients rebleeded at the end of the follow-up. The risk of rebleeding in patients with endoscopic primary prophylaxis decreased by 0.773 times (OR = 0.227, 95%CI: 0.139–0.372, P < 0.001) after adjusting covariables. Subgroups were divided according to the Child-Pugh (CP) score, and the results revealed that the risk of rebleeding in patients with endoscopic primary prophylaxis decreased by 0.858 times in Grade A patients (OR = 0.142, 95%CI: 0.066–0.304, P < 0.001) and 0.804 times in Grade B patients (OR = 0.196, 95%CI: 0.085–0.451, P < 0.001) compared with patients without endoscopic primary prophylaxis, but showed no difference in Grade C patients.

Conclusion

Endoscopic primary prophylaxis was associated with a decreased risk of rebleeding in liver cirrhosis patients with EGVB after endoscopic therapy, which suggested that clinicians should pay more attention to endoscopic primary prophylaxis to prevent the occurrence of rebleeding in these patients.

Analysis of US Food and Drug Administration Oncology Approvals on the Characterization of Hepatic Impairment Effect and Dosing Recommendations

Patients with cancer and advanced hepatic impairment (HI) (i.e., moderate and severe impairment) are often excluded from first-in-patient, phase II, and phase III studies. Thus, dose recommendations for this subgroup of patients are often derived using a combination of dedicated phase I studies conducted in participants without cancer and a population pharmacokinetic (PK) modeling approach. A standardized risk-based approach to guide the evaluation of HI in patients with cancer is needed. In this review, we evaluated available oncology drug approvals by the US Food and Drug Administration (FDA) from 1999 to 2019, identified strategies utilized by sponsors to characterize the effect of HI on the PK of oncology drugs, and assessed regulatory expectations for each strategy. Finally, we constructed a decision tree that complements current FDA guidance to enable efficient evaluation of the effect of HI on PK and provide guidance for dose recommendations.

Pharmacokinetics of Ipatasertib in Subjects With Hepatic Impairment Using Two Methods of Classification of Hepatic Function

Ipatasertib is a highly selective small-molecule pan-Akt inhibitor in clinical development. Ipatasertib is predominantly eliminated by the liver, and therefore the effect of hepatic impairment on ipatasertib pharmacokinetics (PK) was evaluated. In this Phase I open-label, parallel group study, the PK of ipatasertib was evaluated in subjects with hepatic impairment based on both, the Child-Pugh and the National Cancer Institute-Organ Dysfunction Working Group (NCI-ODWG) classification for hepatic impairment. A single dose of ipatasertib at 100 mg was administered and the PK was characterized in healthy subjects with normal hepatic function or mild, moderate and severe hepatic impairment. Based on Child-Pugh classification, subjects with moderate or severe hepatic impairment had an approximately 2- and 3-fold increase in systemic exposure (AUC_0-∞ ) to ipatasertib, respectively, compared to subjects with normal hepatic function. Systemic exposure (AUC_0-∞ ) to ipatasertib in subjects with mild hepatic impairment was comparable to that in subjects with normal hepatic function. In accordance with reduced clearance capacity, subjects with mild to severe hepatic impairment showed lower systemic exposure (AUC_0-∞ ) of ipatasertib metabolite M1 (G-037720). Overall results were comparable between Child-Pugh and NCI-ODWG classification criteria. Based upon the results from this study, no dosage adjustment is required for ipatasertib when treating patients with mild hepatic impairment, whereas a dose reduction would be recommended for subjects with moderate or severe hepatic impairment. Based on real world data analysis, ∼2% of intended patient population is expected to need a modified dose due to moderate or severe hepatic impairment. This article is protected by copyright. All rights reserved.

A Narrative Review of the Clinical Practicalities of Bamlanivimab and Etesevimab Antibody Therapies for SARS-CoV-2

The severity of coronavirus disease 2019 (COVID-19) ranges from mild to death, with high morbidity and mortality rates reported amongst a vulnerable subset of patients termed high risk. While vaccines remain the primary option for COVID-19 prevention, neutralizing monoclonal antibodies (mAbs), such as bamlanivimab and etesevimab, have been shown to benefit certain subpopulations after exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Unlike vaccine-derived immunity that develops over time, administration of neutralizing mAbs is an immediate and passive immunotherapy, with the potential to reduce disease progression, emergency room visits, hospitalizations, and death. Bamlanivimab alone and together with etesevimab hold emergency use authorizations in several countries globally, with countries increasingly transitioning to the use of bamlanivimab and etesevimab together and other authorized mAbs on the basis of their evolving variant landscape, regulatory authorizations, and access to drugs. The current guidelines for the administration of bamlanivimab alone or together with etesevimab are informed by an iterative process of testing and development. Herein the rationale for these guidelines is provided by sharing the learnings that have been gathered throughout the development process of these mAbs. In addition, this review addresses the most common clinical questions received from health care professionals (HCPs) and patients regarding indicated population, dose, use with other medications and vaccines, duration of protection, and variants in clinical practice. As prevalence of SARS-CoV-2 variants can differ by country and state, prescribing HCPs should consider the prevalence of bamlanivimab and etesevimab resistant variants in their area, where data are available, regarding potential efficacy impact when considering treatment options.

Trial Registration: ClinicalTrials.gov identifier: NCT04427501; NCT04411628; NCT04497987; NCT04634409.

Proteomic Quantification of Changes in Abundance of Drug-Metabolizing Enzymes and Drug Transporters in Human Liver Cirrhosis: Different Methods, Similar Outcomes

Model-based assessment of the effects of liver disease on drug pharmacokinetics requires quantification of changes in enzymes and transporters responsible for drug metabolism and disposition. Different proteomic methods are currently used for protein quantification in tissues and in vitro systems, each with specific procedures and requirements. The outcome of quantitative proteomic assays using four different methods (one targeted and three label-free) applied to the same sample set was compared in this study. Three pooled cirrhotic liver microsomal samples corresponding to cirrhosis with nonalcoholic fatty liver disease, biliary disease, or cancer and a control microsomal pool were analyzed using quantification concatemer-based targeted proteomics, the total protein approach (TPA), high three ion intensity (Hi3) approach, and intensity-based absolute quantification (iBAQ) to determine the absolute and relative abundance in disease compared with control. The relative abundance data provided a "disease perturbation factor" (DPF) for each target protein. Absolute and relative abundances generated by standard-based label-free methods (iBAQ and Hi3) showed good agreement with targeted proteomics (limited bias and scatter), but TPA (standard-free method) overestimated absolute abundances by approximately 2-fold. The DPF was consistent between different proteomic methods but varied between enzymes and transporters, indicating discordance of effects of cirrhosis on various metabolism-related proteins. The DPF ranged from no change (e.g., for glucuronosyltransferase-1A6 in nonalcoholic fatty liver disease group) to less than 0.3 (e.g., carboxylesterases-1 in cirrhosis of biliary origin). SIGNIFICANCE STATEMENT: This study demonstrated that relative changes in enzymes and transporters (DPF) are independent of the quantitative proteomic methods used. Standard-based label-free methods, such as high three ion intensity (Hi3) and intensity-based absolute quantification (iBAQ) methods, were less biased and more precise than the total protein approach (TPA) when compared with targeted data. The DPF reconciled differences across proteomic methods observed with absolute levels. Using this approach, differences were revealed in the expression of enzymes/transporters in cirrhosis associated with different etiologies.

Pharmacokinetics and safety of rucaparib in patients with advanced solid tumors and hepatic impairment

PURPOSE

The poly(ADP-ribose) polymerase inhibitor rucaparib is approved for the treatment of patients with recurrent ovarian and metastatic castration-resistant prostate cancer; however, limited data are available on its use in patients with hepatic dysfunction. This study investigated whether hepatic impairment affects the pharmacokinetics, safety, and tolerability of rucaparib in patients with advanced solid tumors.

METHODS

Patients with normal hepatic function or moderate hepatic impairment according to the National Cancer Institute Organ Dysfunction Working Group (NCI-ODWG) criteria were enrolled and received a single oral dose of rucaparib 600 mg. Concentrations of rucaparib and its metabolite M324 in plasma and urine were measured. Pharmacokinetic parameters were compared between hepatic function groups, and safety and tolerability were assessed.

RESULTS

Sixteen patients were enrolled (n = 8 per group). Rucaparib maximum concentration (Cmax) was similar, while the area under the concentration-time curve from time 0 to infinity (AUC0-inf) was mildly higher in the moderate hepatic impairment group than in the normal control group (geometric mean ratio, 1.446 [90% CI 0.668-3.131]); similar trends were observed for M324. Eight (50%) patients experienced ≥ 1 treatment-emergent adverse event (TEAE); 2 had normal hepatic function and 6 had moderate hepatic impairment.

CONCLUSION

Patients with moderate hepatic impairment showed mildly increased AUC0-inf for rucaparib compared to patients with normal hepatic function. Although more patients with moderate hepatic impairment experienced TEAEs, only 2 TEAEs were considered treatment related. These results suggest no starting dose adjustment is necessary for patients with moderate hepatic impairment; however, close safety monitoring is warranted.

Review article: time to revisit Child-Pugh score as the basis for predicting drug clearance in hepatic impairment

BACKGROUND

Prescription information for many drugs entering the market lacks dosage guidance for hepatic impairment. Dedicated studies for assessing the fate of drugs in hepatic impairment commonly stratify patients using Child-Pugh score. Child-Pugh is a prognostic clinical score with limitations in reflecting the liver's metabolic capacity.

AIMS

To demonstrate the need for better drug dosing approaches in hepatic impairment, summarise the current status, identify knowledge gaps related to drug kinetic parameters in hepatic impairment, propose solutions for predicting the liver disease impact on drug exposure and discuss barriers to dosing guidance in those patients.

METHODS

Relevant reports on dosage adjustment in hepatic impairment were analysed concerning the prediction of the impairment impact on drug kinetics using physiologically-based pharmacokinetic (PBPK) modelling.

RESULTS

PBPK models are suggested as a potential framework to understand drug clearance changes in hepatic impairment. Quantifying changes in abundance and activity of drug-metabolising enzymes and transporters, understanding the impact of shunting, and accounting for interindividual variations in drug absorption could help in extending the success of these models in hepatically-impaired populations. These variables might not correlate with Child-Pugh score as a whole. Therefore, new metabolic activity markers, imaging techniques and other scoring systems are proposed to either support or substitute Child-Pugh score.

CONCLUSIONS

Many physiological changes in hepatic impairment determining the fate of drugs do not necessarily correlate with Child-Pugh score. Quantifying these changes in individual patients is essential in future hepatic impairment studies. Further studies assessing Child-Pugh alternatives are recommended to allow better prediction of drug exposure.

Atezolizumab and Bevacizumab in Patients with Unresectable Hepatocellular Carcinoma: Pharmacokinetic and Safety Assessments Based on Hepatic Impairment Status and Geographic Region

INTRODUCTION

Phase 1b GO30140 and phase 3 IMbrave150 studies evaluated first-line atezolizumab + bevacizumab for unresectable hepatocellular carcinoma (HCC). Here, we evaluated pharmacokinetics (PK) and safety by hepatic impairment status and geographic region.

METHODS

Patients received atezolizumab 1,200 mg + bevacizumab 15 mg/kg IV every 3 weeks. Drug concentrations were evaluated by descriptive statistics and population PK. PK and adverse event frequencies were evaluated by hepatic impairment status and region.

RESULTS

323 IMbrave150 patients and 162 GO30140 patients were PK evaluable. Compared with IMbrave150 patients who had normal hepatic function per the National Cancer Institute Organ Dysfunction Working Group (NCI-ODWG) criteria (n = 123), patients with mild impairment (n = 171) had a geometric mean ratio (GMR) of 0.92 for cycle 1 atezolizumab area under the concentration-time curve (AUC); patients with moderate impairment (n = 27) had a GMR of 0.88. Patients in Asia ([n = 162] vs. outside [n = 161]) had a GMR of 1.25 for cycle 1 atezolizumab AUC. Compared with GO30140 patients who had normal hepatic function (NCI-ODWG [n = 61]), patients with mild impairment (n = 92) had a GMR of 0.97 for cycle 1 peak bevacizumab concentrations; those with moderate impairment (n = 9) had a GMR of 0.94. Patients in Asia (n = 111) versus outside Asia (n = 51) had a GMR of 0.94 for cycle 1 peak bevacizumab concentration. PK results were generally comparable when evaluated based on additional hepatic functional definitions (Child-Pugh or albumin/bilirubin criteria) or study enrollment in Japan. No associations between atezolizumab PK and HCC etiology were seen. Adverse event frequencies were similar across evaluated groups.

CONCLUSIONS

IMbrave150 and GO30140 patients with unresectable HCC had varying baseline hepatic impairment and high enrollment from Asia. PK data demonstrated considerable exposure overlap across groups. Treatment was tolerable across groups. No need for dose adjustment based on mild or moderate hepatic impairment or region is recommended based on this analysis.

A review of the evidence base for utilizing Child-Pugh criteria for guiding dosing of anticancer drugs in patients with cancer and liver impairment

As the liver is vital for the metabolism of many anticancer drugs, determining the correct starting doses in cancer patients with liver impairment is key to safe prescription and prevention of unnecessary adverse effects. Clinicians typically use liver function tests when evaluating patients; however, prescribing information and summaries of product characteristics often suggest dosing of anticancer drugs in patients with liver impairment based on the Child-Pugh criteria, even though the criteria were not developed for this purpose. In this review, we assessed all the oncological small molecule and cytotoxic drugs approved by the United States Food and Drug Administration (FDA) over a 5-year period from 2014 to 2018. The various entry criteria related to these drugs—with respect to hepatic function—in key pivotal studies were compared with their approved dosing recommendations found in prescribing information and summaries of product characteristics. We found that 46% of drugs have dosing recommendations based on Child-Pugh criteria alone, despite the fact that only 8% of these drugs were tested within studies that used the Child-Pugh criteria as entry criteria. Moreover, we note that the data used to make recommendations based on Child-Pugh criteria are typically from small studies that may lack an appropriate patient population. We propose that these findings, along with details surrounding the development of the Child-Pugh criteria, call into question the validity and appropriateness of using Child-Pugh criteria for dosing recommendations of anticancer drugs.

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Dosing information for anticancer drugs in patients with liver impairment is often based on the Child-Pugh criteria.

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Clinical trials and clinicians typically use liver function tests when evaluating patients.

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Of the 39 oncologic drugs examined, almost half (46%) had dosing recommendations based on Child-Pugh criteria alone.

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We question whether using Child-Pugh criteria for dosing recommendations of anticancer drugs is the best approach.