Dirk Trommeshauser

Phase I Dose Escalation and Pharmacokinetic Study of BI 2536, a Novel Polo-Like Kinase 1 Inhibitor, in Patients With Advanced Solid Tumors

PURPOSE BI 2536 is a novel, potent, and highly specific inhibitor of polo-like kinase 1 (Plk1), which has an essential role in the regulation of mitotic progression. The aim of this trial was to identify the maximum tolerated dose (MTD) of BI 2536 and to determine the safety, pharmacokinetics, and antitumor activity in patients who had advanced solid tumors. PATIENTS AND METHODS This phase I trial followed an open label, toxicity-guided, dose-titration design. Single doses of BI 2536 (25 to 250 mg) were administered as a 1-hour intravenous infusion; patients who experienced clinical benefit were eligible for additional treatment courses. Safety and pharmacokinetics were investigated. Tumor response was evaluated according to Response Evaluation Criteria in Solid Tumors Group guidelines. RESULTS The MTD was defined at 200 mg in a total of 40 patients entered; reversible neutropenia constituted the dose-limiting toxicity (DLT) and the most frequent adverse event at the MTD (grade 3 to 4; 56%). Nausea (52%), fatigue (52%), and anorexia (44%) also were common and were mostly of mild to moderate intensity (Common Terminology Criteria of Adverse Events <or= grade 2). One patient experienced a transient partial response. At doses equal to or greater than the MTD, 23% of patients experienced disease stabilization for 3 or more months. Dose-proportional increases in the maximum plasma concentration and total exposure were observed. BI 2536 showed a high total clearance and high distribution into tissue. CONCLUSION The MTD of BI 2536 when administered as a single-dose, 1-hour infusion was 200 mg; BI 2536 was well tolerated and showed a favorable pharmacokinetic profile. Antitumor activity of BI 2536 was observed.

An Open-Label, Phase I Study of the Polo-like Kinase-1 Inhibitor, BI 2536, in Patients with Advanced Solid Tumors

Purpose: This phase I, open-label, dose-escalation study investigated the maximum tolerated dose (MTD) of BI 2536, a small-molecule polo-like kinase (Plk)–1 inhibitor, in two treatment schedules in patients with advanced solid tumors. Secondary objectives included evaluation of safety, efficacy, and pharmacokinetics. Experimental Design: Patients received a single i.v. dose of BI 2536 as a 1-hour infusion on days 1 and 8 or a single 24-hour infusion on day 1 of each 21-day treatment course. MTD determination was based on dose-limiting toxicities. Results: Forty-four and 26 patients received each treatment schedule, respectively. The MTD of BI 2536 in the day 1 and 8 schedule was 100 mg per administration (200 mg per course). The MTD for the second dosing schedule was not determined; a 225-mg dose was well tolerated. The most frequently reported treatment-related nonhematologic adverse events were gastrointestinal events and fatigue. Hematotoxicity as the most relevant side effect was similar in both schedules; neutropenia grades 3 and 4 were observed in 16 patients (36.4%) of the day 1 and 8 schedule and 13 patients (50%) of the 24-hour infusion. Fourteen patients (32%) treated in the day 1 and 8 dosing schedule had a best overall response of stable disease. Plasma concentrations of BI 2536 increased dose proportionally, with no relevant accumulation of exposure in the day 1 and 8 dosing schedule. The average terminal half-life was 50 hours. Conclusions: BI 2536 administered in either treatment schedule has adequate safety in patients with advanced solid tumors, warranting further clinical investigation of polo-like kinase–1 inhibitors. Clin Cancer Res; 16(18); 4666–74. ©2010 AACR.

Phase i study of the Plk1 inhibitor BI 2536 administered intravenously on three consecutive days in advanced solid tumours

BACKGROUND This open-label phase i study with an accelerated titration design was performed to determine the maximum tolerated dose of BI 2536, a potent, highly selective small-molecule polo-like kinase 1 (Plk1) inhibitor. METHODS Patients with advanced solid tumours received a single 60-minute intravenous infusion of BI 2536 (50-70 mg) on days 1-3 of each 21-day treatment course. Recipients without disease progression or untenable toxicity could receive additional treatment courses. The maximum tolerated dose was determined based on dose-limiting toxicities. Other assessments included safety, pharmacokinetic profile, and antitumour activity according to the Response Evaluation Criteria in Solid Tumors. RESULTS The study enrolled 21 patients. The maximum tolerated dose for BI 2536 was determined to be 60 mg for the study schedule. Dose-limiting toxicities included hematologic events, hypertension, elevated liver enzymes, and fatigue. The most frequently reported drug-related adverse events were mild-to-moderate fatigue, leukopenia, constipation, nausea, mucosal inflammation, anorexia, and alopecia. The pharmacokinetics of BI 2536 were linear within the dose range tested. Plasma concentration profiles exhibited multi-compartmental pharmacokinetic behaviour, with a terminal elimination half-life of 20-30 hours. CONCLUSIONS In the present study, BI 2536 showed an acceptable safety profile warranting further investigation of Plk1 inhibitors in this patient population.

Ibuprofen Extrudate, a Novel, Rapidly Dissolving Ibuprofen Formulation: Relative Bioavailability Compared to Ibuprofen Lysinate and Regular Ibuprofen, and Food Effect on All Formulations

N anti-inflammatory drugs (NSAIDs), including ibuprofen, have been used for decades in the management of a multitude of pain conditions and rheumatic diseases. Their effects include inhibition of prostaglandin synthesis resulting in analgesic, anti-inflammatory, and antipyretic efficacy. Because of a longstanding and favorable safety record as well as proven efficacy in many different populations and indications, the popularity of ibuprofen is ever increasing. The vast majority of indications for pain treatment requires an onset of action as quickly as possible. For an oral administration drug, the time to onset of a desired pharmacological effect depends on many successive steps: dissolution of the formulation, passage to the site of absorption (usually the jejunal parts of the small intestine), permeation through physiological membranes, entry into the portal vein circulation (with potential enteric or hepatic first-pass metabolism), distribution from plasma to the site of action, and interaction with the receptor, which then causes a cascade of events leading to the targeted pharmacological modification. Distribution to other tissues, metabolism, and excretion of the active principle may also affect early availability of the drug at the effector site. For many compounds, the initial rise of the plasma concentration, following oral administration, is critical with regard to time to onset of the desired pharmacological effect. Ibuprofen shows low solubility in aqueous acidic media but is highly permeable through physiological membranes. Bioavailability is close to 100% because of almost complete absorption, but the onset of absorption strongly depends on dissolution and thus on the administered formulation. Different approaches have been made to improve solubility of the active ingredient, such as transferring the substance to a salt (lysinate) or designing a pharmaceutical dosage form that favors a quick release of ibuprofen in the gastrointestinal tract. In the manufacture of ibuprofen extrudate tablets, a special extrusion technology is applied to provide the BRIEF REPORTS/PHARMACOKINETICS

A quantitative enterohepatic circulation model: development and evaluation with tesofensine and meloxicam.

Background and ObjectiveDrugs undergoing enterohepatic circulation (EHC) are associated with typical pharmacokinetic characteristics such as multiple-peak phenomenon in the plasma concentration-time profile and prolongation of the apparent elimination half-life (t1/2). Currently, versatile pharmacokinetic models are lacking that could test the hypothesis of an EHC for observed multiple-peak phenomenon in pharmacokinetic profiles and its quantitative contribution. The aim of this analysis was to accomplish a model that is able to describe typical plasma concentration-time profiles of compounds undergoing EHC using data from intravenous studies of tesofensine and meloxicam. In addition, the developed model should be able to quantify the contribution of an EHC to the pharmacokinetics by determining the influence of interrupting the EHC of tesofensine and meloxicam to various extents.MethodsTwo studies were investigated retrospectively for model development and model evaluation. Twentyone healthy subjects received a single 6-hour infusion of tesofensine (0.3, 0.6, 0.9, 1.2 mg) in a double-blind, randomized, placebo-controlled, single rising-dose study. Twelve healthy subjects were treated in a randomized, crossover study with meloxicam 30 mg as a single dose given intravenously (bolus) either alone or concomitantly with cholestyramine. The EHC model was developed based on data from the tesofensine study, where EHC is suspected. Model evaluation was performed with data from the meloxicam trial. Modelling and simulation analyses were performed using the software programs NONMEM, SAS and Berkeley Madonna.ResultsPlasma concentration-time profiles of tesofensine were best described by a three-compartment model (absorption, central and gallbladder) with first-order elimination. The release of the bile compartment was controlled by a sine function model, switching the bile compartment periodically on and off using the actual clock time as the control element. A four-compartment model (absorption, central, peripheral and gallbladder) with first-order elimination and the sine function for gallbladder control described the meloxicam data best. Coadministration of cholestyramine resulted in a predicted 56% withdrawal of meloxicam from the EHC process causing a reduction in the t1/2 from ∼19 hours to ∼12 hours.ConclusionA quantitative EHC model was successfully developed that was capable of describing the multiple peaks in plasma concentration-time profiles of tesofensine and meloxicam very well. Additionally, the model successfully quantified the observed results for an interruption of the meloxicam EHC. The model offers an in silico method to support an EHC hypothesis using standard pharmacokinetic data and might help to guide dosing recommendations of compounds undergoing EHC.

Contribution of the active metabolite M1 to the pharmacological activity of tesofensine in vivo: a pharmacokinetic‐pharmacodynamic modelling approach

Tesofensine is a centrally acting drug under clinical development for Alzheimers disease, Parkinsons disease and obesity. In vitro, the major metabolite of tesofensine (M1) displayed a slightly higher activity, which however has not been determined in vivo. The aims of this investigation were (i) to simultaneously accomplish a thorough characterization of the pharmacokinetic (PK) properties of tesofensine and M1 in mice and (ii) to evaluate the potency (pharmacodynamics, PD) and concentration‐time course of the active metabolite M1 relative to tesofensine and their impact in vivo using the PK/PD modelling approach.

Semi-Mechanistic Population Pharmacokinetic Drug-Drug Interaction Modelling of a Long Half-Life Substrate and Itraconazole

AbstractBackground: For compounds with a long elimination half-life, the evaluation of a drug-drug interaction (DDI) study can be challenging. The standard analytical approach of a non-compartmental analysis (NCA) might not be able to detect the full interaction potential and may lead to a significant underestimation of the interaction. The most appropriate method for data analysis might be a semi-mechanistic population pharmacokinetic modelling approach. Objectives: To accomplish a semi-mechanistic DDI model for a long-elimination-half-life drug substrate, tesofensine, and the cytochrome P450 (CYP) 3 A4 inhibitor itraconazole, and to compare the results of the semi-mechanistic model with the results obtained from the standard NCA approach. Additionally, the impact of different schedules of itraconazole on tesofensine pharmacokinetics and the general performance of the standard NCA approach were evaluated. Methods: Overall, 28 subjects received a single oral dose of tesofensine 2 mg; 14 of these subjects were coadministered an oral itraconazole 400 mg loading dose and a 200 mg maintenance dose for 6 days before and 5 days after administration of tesofensine. The dataset contained 465 plasma concentrations of tesofensine (full profiles) and 80 plasma concentrations of itraconazole (trough values). First, pharmacokinetic models of itraconazole and tesofensine were developed in parallel. Subsequently, a combined model was developed, taking into account CYP3A4 inhibition. The analyses were performed using NONMEM® software. Results: The plasma concentration-time profiles of itraconazole and tesofensine were best described by a one-compartment model for each drug, with first-order elimination rate constants that were both inhibited by itraconazole concentrations. Inhibition resulted in reduced clearances and prolonged elimination half-lives for tesofensine and itraconazole: using NCA, the actual study revealed an ∼9% increase in exposure for the timeframe of the coadministration with itraconazole (the area under the plasma concentration-time curve (AUC) from 0 to 144 hours [AUC144h]), and the impact on exposure estimated to infinity (AUC∞) was ∼26%. These results are in contrast to the model-predicted results, where the inhibitory effect of itraconazole caused a 38% reduction in the clearance of tesofensine, leading to a 63% increased exposure. Conclusions: This analysis presents a semi-mechanistic population pharmacokinetic approach that may be useful for the evaluation of DDI studies. The model can be an aid in evaluating DDI studies for compounds with a long elimination half-life, especially when the inhibitor cannot be administered over a sufficient period. Additionally, the population model-based approach may allow simplification of the design and the analysis and interpretation of safety and efficacy findings in DDI studies.

Pharmacokinetic Properties of Nintedanib in Healthy Volunteers and Patients With Advanced Cancer

Nintedanib, a triple angiokinase inhibitor, has undergone clinical investigation for the treatment of solid tumors and idiopathic pulmonary fibrosis. Nintedanib (Vargatef®) plus docetaxel is approved in the EU for the treatment of patients with adenocarcinoma non‐small cell lung cancer (NSCLC) after first‐line chemotherapy, and as monotherapy (Ofev®) in the United States and EU for the treatment of patients with idiopathic pulmonary fibrosis. Pharmacokinetics (PK) of nintedanib after oral single and multiple doses and intravenous (IV) administration were assessed using 3 data sets: (1) an absolute bioavailability trial that enrolled 30 healthy volunteers; (2) a pooled data analysis of 4 studies that enrolled a total of 107 healthy volunteers; and (3) a pooled data analysis of 4 studies that enrolled a total of 149 patients with advanced cancer. In the absolute bioavailability trial of healthy volunteers, nintedanib showed a high total clearance (geometric mean 1390 mL/min) and a high volume of distribution at steady state (Vss = 1050 L). Urinary excretion of IV nintedanib was about 1% of dose; renal clearance was about 20 mL/min and therefore negligible. There was no deviation from dose proportionality after IV administration in the dose range tested. Absolute bioavailability of oral nintedanib (100 mg capsule) relative to IV dosing (4‐hour infusion, 6 mg) was slightly below 5%. Nintedanib was quickly absorbed after oral administration. It underwent rapid and extensive first‐pass metabolism and followed at least biphasic disposition kinetics. In advanced cancer patients, steady state was reached at the latest at 7 days for twice‐daily dosing. Nintedanibs PK was time‐independent; accumulation after repeated administration was negligible.