Trastuzumab Deruxtecan Dosing in Human Epidermal Growth Factor Receptor 2-Positive Gastric Cancer: Population Pharmacokinetic Modeling and Exposure-Response Analysis.

This study evaluated the benefit/risk of trastuzumab deruxtecan (T-DXd) 6.4 mg/kg in patients with human epidermal growth factor receptor 2 (HER2)-positive gastric cancer using pharmacometrics. A population pharmacokinetic (PopPK) model was developed using data from patients with gastric cancer, breast cancer, or other tumors in T-DXd clinical trials, primarily conducted in Asia.

Effect of Trastuzumab Deruxtecan on QT/QTc Interval and Pharmacokinetics in HER2-Positive or HER2-Low Metastatic/Unresectable Breast Cancer.

HER2-targeted anticancer therapies may be associated with cardiovascular adverse events. This study evaluated effects of the HER2-targeted antibody-drug conjugate trastuzumab deruxtecan (T-DXd, DS-8201a) on QT/QTc interval and its pharmacokinetics. Patients with heavily pretreated, metastatic HER2-expressing breast cancer were enrolled at seven study sites in Japan.

Pharmacokinetics, Safety, and Efficacy of Trastuzumab Deruxtecan with Concomitant Ritonavir or Itraconazole in Patients with HER2-Expressing Advanced Solid Tumors.

Purpose: To evaluate drug-drug interactions between the human epidermal growth factor receptor 2 (HER2)-targeted antibody-drug conjugate trastuzumab deruxtecan (T-DXd; DS-8201a) and the OATP1B/CYP3A inhibitor ritonavir or the strong CYP3A inhibitor itraconazole.

Patients And Methods: Patients with HER2-expressing advanced solid tumors were enrolled in this phase I, open-label, single-sequence crossover study (NCT03383692) and received i.v.

[Pharmacological and clinical study results of trastuzumab deruxtecan (T-DXd, ENHERTU)].

Antibody-drug conjugates (ADCs) combine the specific antibody and cytotoxic agent by a linker and represent a promising drug class with a wider therapeutic window than conventional chemotherapeutic agents by substantiating efficient and specific drug delivery to antigen-expressing tumor cells. However, there are rooms for improvement in terms of efficacy, safety, physicochemical property; therefore, the development of promising ADC drugs across multiple indications are eagerly awaited. In 2015, Daiichi Sankyo initiated the first-in-human study of HER2 ADC, trastuzumab deruxtecan (T-DXd, ENHERTU) which possesses DNA topoisomerase I inhibitor, exatecan derivative and proprietary linker, in Japan.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of the afucosylated, humanized anti-EPHA2 antibody DS-8895a: a first-in-human phase I dose escalation and dose expansion study in patients with advanced solid tumors.

Background: Erythropoietin-producing hepatocellular receptor A2 (EPHA2) is overexpressed on the cell surface in many cancers and predicts poor prognosis. DS-8895a is a humanized anti-EPHA2 IgG1 monoclonal antibody afucosylated to enhance antibody-dependent cellular cytotoxicity activity. We conducted a two-step, phase I, multicenter, open-label study to determine the safety, tolerability, and pharmacokinetics of DS-8895a in patients with advanced solid tumors.

Effect of DS-8500a, a Novel G Protein-Coupled Receptor 119 Agonist, on the Pharmacokinetics of Rosuvastatin and Atorvastatin in Healthy Subjects.

Background: Non-clinical study data suggest that DS-8500a, a G protein-coupled receptor 119 agonist, exhibits antidiabetic activity, inhibition of some transporters and induction of cytochrome P450 (CYP) 3A. Statins are substrates for some transporters and CYP3A that may be coadministered with DS-8500a in clinical practice.

Objective: To determine the potential effects of DS-8500a on the pharmacokinetics of statins, we evaluated the effects of repeated oral administration of DS-8500a 75 mg on the pharmacokinetics of rosuvastatin and atorvastatin in healthy adults.

Pharmacokinetics and Safety of DS-8500a, an Antidiabetic Drug, in Japanese Subjects with Hepatic or Renal Impairment: A Single-Center, Open-Label, Single-Dose Study.

Introduction: The pharmacokinetics, safety, and tolerability of DS-8500a (a G protein receptor 119 agonist) up to 100 mg have been investigated in healthy Japanese adults. The objective of this study was to evaluate the effects of hepatic or renal impairment on the pharmacokinetics of a single 25-mg oral dose of DS-8500a.

Methods: This single-center, open-label study enrolled subjects into eight groups according to hepatic function (normal; mild or moderate impairment) and renal function [normal; mild, moderate, or severe impairment; and end-stage renal disease (ESRD)].

Safety and Pharmacokinetics of DS-8500a, a Novel GPR119 Agonist, After Multiple Oral Doses in Healthy Japanese Males.

Background And Objectives: G protein-coupled receptor 119 (GPR119) agonists reduce plasma glucose by promoting insulin secretion in a glucose-dependent manner. We evaluated the safety and pharmacokinetics of multiple oral doses of DS-8500a, a GPR119 agonist, under fed conditions in healthy adult Japanese male subjects.

Methods: In this Phase 1, randomized, placebo-controlled, double-blind, multiple oral dose study, participants were aged ≥ 20 and ≤ 45 years with a body mass index ≥ 18.

Phase 1 study of new formulation of patritumab (U3-1287) Process 2, a fully human anti-HER3 monoclonal antibody in combination with erlotinib in Japanese patients with advanced non-small cell lung cancer.

Background: This phase 1 study evaluated the safety, tolerability, pharmacokinetics and efficacy of patritumab (U3-1287) Process 2, a new formulation of fully human anti-HER3 monoclonal antibody in combination with erlotinib, an epidermal growth factor receptortyrosine kinase inhibitor (EGFR-TKI) in prior chemotherapy treated Japanese patients with advanced non-small cell lung cancer (NSCLC).

Methods: Patients received intravenous patritumab Process 2 formulation at 9 mg/kg every 3 weeks after initiation of 18 mg/kg loading dose combined with continuous daily dose of erlotinib (150 mg QD) until any of the withdrawal criteria are met. Adverse events (AEs) were assessed using CTCAE v4.

Metabolism and disposition of [(14)C]tivantinib after oral administration to humans, dogs and rats.

1. The biotransformation and disposition of tivantinib in humans, dogs and rats was examined after a single oral administration of [(14)C]tivantinib. Tivantinib constituted no more than one-third of the plasma radioactivity in all species, demonstrating significant contribution of the metabolites to plasma radioactivity.

Human small intestinal and colonic tissue mounted in the Ussing chamber as a tool for characterizing the intestinal absorption of drugs.

The purpose of this study was to validate human small intestinal and colonic tissue mounted in the Ussing chamber as a tool for predicting the oral drug absorption in humans with the main focus on moderately and poorly permeable compounds. The obtained apparent permeability coefficient (P(app)) of eleven test compounds was compared to their fraction absorbed (Fa) in humans taken from the literature. Beside the conventional P(app) a new parameter, the apparent permeability coefficient total (P(app,total)), involving both the apical-to-basolateral permeability and the time-dependent compound accumulation in the tissue was established.

Synthesis and evaluation of CS-2100, a potent, orally active and S1P(3)- sparing S1P(1) agonist.

Modulators of sphingosine phosphate receptor-1 (S1P(1)) have recently been focused as a suppressant of autoimmunity. We have discovered a 4-ethylthiophene-based S1P(1) agonist 1-({4-Ethyl-5-[5-(4-phenoxyphenyl)-1,2,4-oxadiazol-3-yl]-2-thienyl}methyl)azetidine-3-carboxylic acid (CS-2100, 8) showing potent S1P(1) agonist activity against S1P(3) and an excellent in vivo potency. We report herein the synthesis of CS-2100 (8) and pharmacological effects such as S1P(1) and S1P(3) agonist activity in vitro, peripheral blood lymphocyte lowering effects and the suppressive effects on adjuvant-induced arthritis and experimental autoimmune encephalomyelitis (EAE) in animal models.

Interaction of angiotensin II type 1 receptor blockers with P-gp substrates in Caco-2 cells and hMDR1-expressing membranes.

Aims: The inhibitory effect of angiotensin II type 1 receptor blockers (ARBs) on P-glycoprotein (P-gp) was examined to evaluate their clinical drug-drug interaction (DDI) potential.

Main Methods: We performed an inhibition study on the vectorial transport of digoxin, a typical substrate for P-gp, using a human colonic adenocarcinoma cell line, Caco-2 cells, and verapamil-stimulated ATPase activity using human multidrug resistance 1 (hMDR1)-expressing membrane.

Key Findings: The vectorial transport of digoxin was inhibited by candesartan cilexetil, irbesartan and telmisartan with the IC(50) values of 14.

Culture period-dependent change of function and expression of ATP-binding cassette transporters in Caco-2 cells.

The objective of this study was to determine an appropriate culture period to assess whether a compound of interest is transported by efflux transporters such as human multidrug resistance 1 (hMDR1), human multidrug resistance-associated protein 2 (hMRP2), and human breast cancer resistance protein (hBCRP) in Caco-2 cells. Caco-2 cells were cultured on a Transwell for 1 to 6 weeks. The expression of these transporters in the mRNA and protein levels was examined using a real-time polymerase chain reaction and Western blotting, respectively.

Inhibitory effects of angiotensin receptor blockers on CYP2C9 activity in human liver microsomes.

We investigated the inhibitory effects of the angiotensin receptor blockers (ARBs), candesartan, irbesartan, losartan, losartan active metabolite (EXP-3174), olmesartan, telmisartan and valsartan (0.3-300 microM), on the CYP2C9 activity in human liver microsomes using (S)-(-)-warfarin as a typical CYP2C9 substrate. Except for olmesartan and valsartan, these ARBs inhibited the activity of 7-hydroxylation of (S)-(-)-warfarin with IC50 values of 39.

Multiple human isoforms of drug transporters contribute to the hepatic and renal transport of olmesartan, a selective antagonist of the angiotensin II AT1-receptor.

Olmesartan, a novel angiotensin II AT1-receptor antagonist, is excreted into both bile and urine, with minimal metabolism. Because olmesartan is a hydrophilic anionic compound, some transporters could be involved in its hepatic and renal clearance. In this study, we characterized the role of human drug transporters in the pharmacokinetics of olmesartan and determined the contribution of each transporter to the overall clearance of olmesartan.

Characterization of CS-023 (RO4908463), a novel parenteral carbapenem antibiotic, and meropenem as substrates of human renal transporters.

To characterize the renal handling of CS-023 (RO4908463), a novel parenteral carbapenem antibiotic, and meropenem in humans, we examined their affinities as substrates to human renal transporters. In vitro studies on the uptake of [14C]CS-023 and [14C]meropenem were conducted using HEK293 cells expressing human organic anion transporters (hOAT) 1, hOAT3, hOAT4, and the human organic cation transporters (hOCT) 1 and hOCT2. CS-023 did not serve as the substrate for any of the transporters tested.