Dose adjustment of venetoclax when co-administered with posaconazole: clinical drug-drug interaction predictions using a PBPK approach.

Purpose: Venetoclax, a targeted anticancer agent approved for the treatment of chronic lymphocytic leukemia and acute myeloid leukemia, is a substrate of cytochrome P450 (CYP) 3A enzyme (CYP3A4). Posaconazole, commonly used to prevent invasive fungal infections in neutropenic patients with hematological malignancies, potently inhibits CYP3A4. The purpose of this evaluation was to predict venetoclax exposures following co-administration of posaconazole at doses not previously studied clinically.

Informing Development of Bispecific Antibodies Using Physiologically Based Pharmacokinetic-Pharmacodynamic Models: Current Capabilities and Future Opportunities.

Antibody therapeutics continue to represent a significant portion of the biotherapeutic pipeline, with growing promise for bispecific antibodies (BsAbs). BsAbs can target 2 different antigens at the same time, such as simultaneously binding tumor-cell receptors and recruiting cytotoxic immune cells. This simultaneous engagement of 2 targets can be potentially advantageous, as it may overcome disadvantages posed by a monotherapy approach, like the development of resistance to treatment.

Mechanistic Modeling of Intra-Tumor Spatial Distribution of Antibody-Drug Conjugates: Insights into Dosing Strategies in Oncology.

Antibody drug conjugates (ADCs) provide targeted delivery of cytotoxic agents directly inside tumor cells. However, many ADCs targeting solid tumors have exhibited limited clinical efficacy, in part, due to insufficient penetration within tumors. To better understand the relationship between ADC tumor penetration and efficacy, previously applied Krogh cylinder models that explore tumor growth dynamics following ADC administration in preclinical species were expanded to a clinical framework by integrating clinical pharmacokinetics, tumor penetration, and tumor growth inhibition.

Quantitative Systems Pharmacology Approaches for Immuno-Oncology: Adding Virtual Patients to the Development Paradigm.

Drug development in oncology commonly exploits the tools of molecular biology to gain therapeutic benefit through reprograming of cellular responses. In immuno-oncology (IO) the aim is to direct the patient's own immune system to fight cancer. After remarkable successes of antibodies targeting PD1/PD-L1 and CTLA4 receptors in targeted patient populations, the focus of further development has shifted toward combination therapies.

Quantitative Assessment of Elagolix Enzyme-Transporter Interplay and Drug-Drug Interactions Using Physiologically Based Pharmacokinetic Modeling.

Introduction: Elagolix is approved for the management of moderate-to-severe pain associated with endometriosis. The aim of this analysis was to develop a physiologically based pharmacokinetic (PBPK) model that describes the enzyme-transporter interplay involved in the disposition of elagolix and to predict the magnitude of drug-drug interaction (DDI) potential of elagolix as an inhibitor of P-glycoprotein (P-gp) and inducer of cytochrome P450 (CYP) 3A4.

Methods: A PBPK model (SimCYP version 15.

Influence of Renal Function on Evolocumab Exposure, Pharmacodynamics, and Safety.

We evaluated the pharmacokinetics, pharmacodynamics, and safety of evolocumab, a fully human monoclonal antibody against proprotein convertase subtilisin kexin type 9 (PCSK9), in an open-label, parallel-design study in participants with normal renal function (n = 6), severe renal impairment (RI; n = 6), or end-stage renal disease (ESRD) receiving hemodialysis (n = 6) who received a single 140-mg dose of evolocumab. The effects of evolocumab treatment on low-density lipoprotein cholesterol (LDL-C) lowering and unbound PCSK9 concentrations were similar in the normal renal function group and the renally impaired groups. Geometric mean C and AUC values in the severe RI and ESRD hemodialysis groups compared with the normal renal function group were lower but within 37% of the normal renal function group (Jonckheere-Terpstra trend test; C , P = .

Accelerating Drug Development in Pediatric Oncology With the Clinical Pharmacology Storehouse.

Pediatric drug development is a challenging process due to the rarity of the population, the need to meet regulatory requirements across the globe, the associated uncertainty in extrapolating data from adults, the paucity of validated biomarkers, and the lack of systematic testing of drugs in pediatric patients. In oncology, pediatric drug development has additional challenges that have historically delayed availability of safe and effective medicines for children. In particular, the traditional approach to pediatric oncology drug development involves conducting phase 1 studies in children once the drug has been characterized and in some cases approved for use in adults.

Receiver Operating Characteristic Analysis and Clinical Trial Simulation to Inform Dose Titration Decisions.

Optimal dose selection in clinical trials is problematic when efficacious and toxic concentrations are close. A novel quantitative approach follows for optimizing dose titration in clinical trials. A system of pharmacokinetics (PK), pharmacodynamics, efficacy, and toxicity was simulated for scenarios characterized by varying degrees of different types of variability.

Comparison of LDL-C Reduction Using Different Evolocumab Doses and Intervals: Biological Insights and Treatment Implications.

Background: The proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor evolocumab reduces low-density lipoprotein cholesterol (LDL-C) and the risk of cardiovascular events.

Objectives: To compare LDL-C reduction using evolocumab 140 mg once every 2 weeks (Q2W) or 420 mg monthly (QM) versus lower doses (70 mg Q2W or 280 mg QM) or placebo.

Methods: Patients received evolocumab 70 or 140 mg Q2W, 280 or 420 mg QM, or placebo Q2W or QM in two 12-week phase 2 studies: one with and one without statins.

Population pharmacokinetics and exposure-response modeling and simulation for evolocumab in healthy volunteers and patients with hypercholesterolemia.

Evolocumab, a novel human monoclonal antibody, inhibits proprotein convertase subtilisin/kexin type 9, a protein that targets low-density lipoprotein-cholesterol (LDL-C) receptors for the treatment of hyperlipidemia. The primary objective of this analysis was to characterize the population pharmacokinetics (popPK) and exposure-response relationship of evolocumab to assess if dose adjustment is needed across differing patient populations. Data were pooled for 5474 patients in 11 clinical studies who received evolocumab doses of 7-420 mg at various frequencies, either intravenously or subcutaneously.

Clinical Pharmacokinetics and Pharmacodynamics of Evolocumab, a PCSK9 Inhibitor.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) increases plasma low-density lipoprotein cholesterol (LDL-C) by decreasing expression of the LDL receptor on hepatic cells. Evolocumab is a human monoclonal immunoglobulin G2 that binds specifically to human PCSK9 to reduce LDL-C. Evolocumab exhibits nonlinear kinetics as a result of binding to PCSK9.

Bedside to Bench: Integrating Quantitative Clinical Pharmacology and Reverse Translation to Optimize Drug Development.

With so much emphasis on reducing attrition and becoming more efficient in the delivery of healthcare, there are many opportunities to leverage existing clinical data in drug development and to foster the practice of reverse translation. The application of quantitative approaches to convert clinical trial and real-world data to knowledge will continue to drive innovation. Herein we discuss recent examples of reverse translation and consider future opportunities to capture critical clinical knowledge to inform decision-making in drug development.

Population Pharmacokinetic and Pharmacodynamic Modeling of Etelcalcetide in Patients with Chronic Kidney Disease and Secondary Hyperparathyroidism Receiving Hemodialysis.

Introduction: Etelcalcetide is a novel calcimimetic that binds and activates calcium-sensing receptors (CaSRs) for the treatment of secondary hyperparathyroidism (SHPT).

Methods: To assess titrated dosing regimens, population pharmacokinetic (PK) and PK/pharmacodynamic (PKPD) modeling of etelcalcetide was performed using NONMEM 7.2.

Association Between Circulating Baseline Proprotein Convertase Subtilisin Kexin Type 9 Levels and Efficacy of Evolocumab.

Importance: Levels of proprotein convertase subtilisin kexin type 9 (PCSK9) vary markedly across the population and are influenced by genetic and nongenetic factors. Evolocumab is a fully human, monoclonal antibody against PCSK9 that reduces low-density lipoprotein cholesterol (LDL-C) levels by 55% to 75%. Whether the efficacy of evolocumab varies based on an individual's baseline PCSK9 level remains unknown.

SRM-based measurements of proprotein convertase subtilisin/kexin type 9 and lipoprotein(a) kinetics in nonhuman primate serum.

Aim: PCSK9 and Lp(a) have been identified as potential biomarkers for cardiovascular disease. The ability to measure protein turnover rates will provide insights into the dynamic properties of these proteins and lead to better understanding of their biological roles. We aimed to implement the stable isotope-labeled tracers ([H]-leucine) and develop a novel LC-selected reaction monitoring (SRM) mass spectrometry (MS) method to study the kinetics of PCSK9 and Lp(a).

Impact of Target-Mediated Elimination on the Dose and Regimen of Evolocumab, a Human Monoclonal Antibody Against Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9).

Understanding the pharmacokinetic (PK) and pharmacodynamic (PD) relationship of a therapeutic monoclonal antibody against proprotein convertase subtilisin/kexin type 9 (PCSK9) exhibiting target-mediated drug disposition (TMDD) is critical for selecting optimal dosing regimens. We describe the PK/PD relationship of evolocumab using a mathematical model that captures evolocumab binding and removal of unbound PCSK9 as well as reduction in circulating low-density lipoprotein cholesterol (LDL-C). Data were pooled from 2 clinical studies: a single-dose escalation study in healthy subjects (7-420 mg SC; n = 44) and a multiple-dose escalation study in statin-treated hypercholesterolemic patients (14 mg weekly to 420 mg monthly [QM] SC; n = 57).

Evaluation of Evolocumab (AMG 145), a Fully Human Anti-PCSK9 IgG2 Monoclonal Antibody, in Subjects With Hepatic Impairment.

Evolocumab binds PCSK9, increasing low-density lipoprotein cholesterol (LDL-C) receptors and lowering LDL-C. Target-mediated evolocumab elimination is attributable to PCSK9 binding. As circulating PCSK9 and LDL-C levels are primarily regulated by the liver, we compared evolocumab pharmacokinetics, pharmacodynamics, and safety in individuals with and without hepatic impairment.

Safety, tolerability, pharmacokinetics, and efficacy of AMG 403, a human anti-nerve growth factor monoclonal antibody, in two phase I studies with healthy volunteers and knee osteoarthritis subjects.

Introduction: Nerve growth factor plays a key role in the pathology of osteoarthritis (OA) related chronic pain. The aim of these studies was to evaluate the safety, tolerability, pharmacokinetics, and clinical response of AMG 403, a human anti-nerve growth factor monoclonal antibody, in healthy volunteers and subjects with knee OA.

Methods: Two phase I, randomized, placebo-controlled, double-blind studies were conducted.

Effects of AMG 145 on low-density lipoprotein cholesterol levels: results from 2 randomized, double-blind, placebo-controlled, ascending-dose phase 1 studies in healthy volunteers and hypercholesterolemic subjects on statins.

Objectives: The aim of this study was to evaluate the safety, tolerability, and effects of AMG 145 on low-density lipoprotein cholesterol (LDL-C) in healthy and hypercholesterolemic subjects on statin therapy.

Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) down-regulates surface expression of the low-density lipoprotein receptor (LDL-R), increasing serum LDL-C. AMG 145, a fully human monoclonal antibody to PCSK9, prevents PCSK9/LDL-R interaction, restoring LDL-R recycling.

Quantitative model of the relationship between dipeptidyl peptidase-4 (DPP-4) inhibition and response: meta-analysis of alogliptin, saxagliptin, sitagliptin, and vildagliptin efficacy results.

Dipeptidyl peptidase-4 (DPP-4) inhibition is a well- characterized treatment for type 2 diabetes mellitus (T2DM). The objective of this model-based meta-analysis was to describe the time course of HbA1c response after dosing with alogliptin (ALOG), saxagliptin (SAXA), sitagliptin (SITA), or vildagliptin (VILD). Publicly available data involving late-stage or marketed DPP-4 inhibitors were leveraged for the analysis.

Target-mediated metabolism and target-mediated drug disposition of the DPPIV inhibitor AMG 222.

Pharmacokinetic and metabolism aspects of AMG 222 interaction with target enzyme, dipeptidylpeptidase IV (DPPIV) were investigated. Inhibition of recombinant human DPPIV by AMG 222 was measured. IC(50) decreased as preincubation time increased.

Quantitative prediction of human pharmacokinetics for monoclonal antibodies: retrospective analysis of monkey as a single species for first-in-human prediction.

Background And Objectives: Prediction of human pharmacokinetics for monoclonal antibodies (mAbs) plays an important role for first-in-human (FIH) dose selection. This retrospective analysis compares observed FIH pharmacokinetic data for 16 mAbs to those predicted in humans based on allometric scaling of Cynomolgus monkey pharmacokinetic data.

Methods: Ten mAbs exhibited linear pharmacokinetics in monkeys based on non-compartmental analysis.

Prediction of exposure-response relationships to support first-in-human study design.

In drug development, phase 1 first-in-human studies represent a major milestone as the drug moves from preclinical discovery to clinical development activities. The safety of human subjects is paramount to the conduct of these studies and regulatory considerations guide activities. Forces of evolution on the pharmaceutical industry are re-shaping the first-in-human dose selection strategy.

Population pharmacokinetic/pharmacodynamic model of subcutaneous adipose 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity after oral administration of AMG 221, a selective 11β-HSD1 inhibitor.

Inhibition of 11β-HSD1 is hypothesized to improve measures of insulin sensitivity and hepatic glucose output in patients with type II diabetes. AMG 221 is a potent, small molecule inhibitor of 11β-HSD1. The objective of this analysis is to describe the pharmacokinetic/pharmacodynamic (PK/PD) relationship between AMG 221 and 11β-HSD1 inhibition in ex vivo adipose tissue samples.

Application of in vivo animal models to characterize the pharmacokinetic and pharmacodynamic properties of drug candidates in discovery settings.

A goal of preclinical discovery is the identification of drug candidates suitable for clinical testing. Successful integration of in vitro and in vivo experimental data sets can afford projections of human dose regimens anticipated to be safe and therapeutically beneficial. While in vitro experiments guide new chemical syntheses and are essential to understanding drug action and disposition, in vivo characterizations provide unique insight into complex biological systems that control concentrations at the site of action and pharmacologic response.