Background Idarucizumab is a monoclonal antibody fragment that reverses dabigatran anticoagulation. Pharmacokinetics (PK) of idarucizumab have been described in healthy, elderly, or renally impaired (RI) volunteers, but PK data in patients are lacking. Objectives This analysis describes the PK of idarucizumab and its target dabigatran in bleeding/surgical patients. Patients and Methods Results from the Reversal Effects of Idarucizumab on Active Dabigatran study, a prospective, multicenter, single-arm study demonstrated the reversal of dabigatran anticoagulation by idarucizumab in patients with uncontrollable bleeding (group A) or who needed urgent surgery (group B). Idarucizumab and unbound dabigatran concentrations, immunogenicity, and pharmacodynamics were assessed. Results Total and unbound dabigatran levels at baseline were 165 ng/mL vs 110 ng/mL and 103 ng/mL vs 69.5 ng/mL in group A and B patients, respectively. Maximum plasma concentrations and area under the curves (AUC(0-24)) of idarucizumab in group A vs B, respectively, were 24 900 nmol/L vs 25 000 nmol/L and 76 600 nmol/h/L vs 68 000 nmol/h/L. Idarucizumab AUC(0-24) increased by 38% in mild, 90% in moderate, and 146% in severe RI patients vs normal renal function. Hepatic impairment or geographical region had no relevant effect on idarucizumab PK. Idarucizumab immediately decreased unbound dabigatran concentration (<20 ng/mL). A linear correlation was observed between unbound dabigatran and diluted thrombin time and ecarin clotting time. Antidrug antibody titers were low (1-64 at day 30; 0-16 at day 90) and had no impact on idarucizumab PK and pharmacodynamics. Conclusion Idarucizumab PK in target patients was consistent with phase I data. Patient characteristics had no impact on PK, whereas RI increased the exposure of idarucizumab and dabigatran. Trial registration number: ClinicalTrials.gov NCT02104947.

AimsPrevious pharmacokinetic characterization of a transporter probe cocktail containing digoxin (P‐gp), furosemide (OAT1, OAT3), metformin (OCT2, MATE1, MATE2‐K) and rosuvastatin (OATP1B1, OATP1B3, BCRP) in healthy subjects showed increases in rosuvastatin systemic exposure compared to rosuvastatin alone. In this trial, the doses of metformin and furosemide as putative perpetrators were reduced to eliminate their drug–drug interaction (DDI) with rosuvastatin.MethodsIn a randomized, open‐label, single‐centre, five‐treatment, five‐period crossover trial, 30 healthy male subjects received as reference treatments separately 0.25 mg digoxin, 1 mg furosemide, 10 mg metformin and 10 mg rosuvastatin, and as test treatment all four drugs administered together as a cocktail. Primary pharmacokinetic endpoints were AUC0‐tz (area under the plasma concentration–time curve from time zero to the last quantifiable concentration) and Cmax (maximum plasma concentration) of each probe drug.ResultsGeometric mean ratios and 90% confidence intervals of test (cocktail) to reference (single drug) for AUC0‐tz were 96.4% (88.2–105.3%) for digoxin, 102.6% (93.8–112.3%) for furosemide, 97.5% (93.5–101.6%) for metformin and 105.0% (96.4–114.4%) for rosuvastatin, indicating lack of interaction. The same analysis for Cmax and for pharmacokinetic parameters of urinary excretion of all cocktail components also indicated no DDI.ConclusionsDigoxin (0.25 mg), furosemide (1 mg), metformin (10 mg) and rosuvastatin (10 mg) exhibit no mutual pharmacokinetic interactions and are well tolerated administered as a cocktail. The cocktail is thus optimized and has the potential to be used as a screening tool for clinical investigation of transporter‐mediated DDI.

Afatinib is an oral irreversible ErbB-Family Blocker indicated for treatment of patients with EGFR mutation positive advanced non-small cell lung cancer. This trial assessed whether renal impairment influences the pharmacokinetics and safety of afatinib.

Essentials Idarucizumab, a monoclonal antibody fragment, binds dabigatran with high affinity and specificity. In this phase 1 trial, healthy Japanese males received idarucizumab alone or with dabigatran. Idarucizumab achieved immediate, complete and sustained reversal of dabigatran anticoagulation. Idarucizumab was well tolerated and demonstrated no pro‐coagulant effects.

In a recently described probe drug cocktail for clinically relevant drug transporters containing digoxin, furosemide, metformin and rosuvastatin, mutual interactions were essentially absent except for increases in the systemic exposure of rosuvastatin. To optimize the cocktail, we further examined the dose dependence of the effects of metformin and furosemide on rosuvastatin pharmacokinetics.

Idarucizumab is an antibody fragment that specifically reverses dabigatran-mediated anticoagulation. Safety, pharmacokinetics and pharmacodynamics of idarucizumab were investigated in dabigatran-treated, middle-aged, elderly and renally impaired volunteers with characteristics similar to patients receiving anticoagulant therapy.

Background: Specific reversal agents for oral anticoagulants may be necessary to manage life-threatening bleeding or prior to emergency surgical procedures. While many reversal agents are in development, idarucizumab is approved and now available commercially in many countries. Idarucizumab is a humanized antibody fragment that specifically binds to dabigatran with high affinity and has shown immediate, complete and sustained reversal of dabigatran-induced anticoagulation in healthy male Caucasian volunteers. The present study investigated the safety, tolerability and pharmacokinetics of idarucizumab (part 1) and explored the effective dose of idarucizumab to reverse the dabigatran-induced anticoagulant effect (part 2) in healthy male Japanese volunteers. Methods: This was a two-part, phase I, randomized, placebo-controlled, double-blind, single-center, rising dose study. In part 1, subjects (n = 32) were randomized to receive either placebo (n = 2/dose group) or single intravenous doses of idarucizumab, 1, 2, or 4 g as a 5-minute infusion or 8 g as a 1-hour infusion (n = 6/group). In part 2, subjects (n = 48) were treated orally for 3 days with dabigatran etexilate (DE, 220 mg bid). On day 4, subjects received a final DE dose, followed a 3-day wash out period. Subjects were again treated orally for 3 days with DE, 220 mg bid. On Day 11, subjects received a final DE dose followed 2 hours later by placebo (n = 3/group) or idarucizumab (1, 2, 4, or 5 g [2.5 g followed by 2.5 g given 15 minutes apart]) as a 5-minute intravenous infusion, n = 9/group). The number of subjects with adverse events (AEs), emergence of anti-idarucizumab antibodies (ADAs), pharmacokinetics and the impact of idarucizumab on coagulation parameters were assessed (diluted thrombin time, ecarin clotting time, activated partial thromboplastin time, and thrombin time). In addition, potential procoagulant effects were monitored as D-dimer and prothrombin fragment F1.2. Results: Idarucizumab attained a maximum concentration in plasma around the end of each infusion followed by a biphasic decline in plasma concentrations with a rapid initial phase and a longer terminal phase.. Dabigatran treatment prolonged the clotting times of all coagulation parameters. Idarucizumab infusion resulted in immediate and complete reversal of dabigatran-induced anticoagulation, reducing coagulation parameters below the upper limit of normal. The duration was dose-dependent; at 4 and 5 g of idarucizumab, complete reversal was sustained up to 72 hours, at lower doses ≤ 2 g a partial return of the anticoagulation activity of dabigatran was observed 1-2 hours after idarucizumab administration. Concentration of unbound dabigatran decreased to below the limit of quantification immediately after administration of a single dose of idarucizumab. Idarucizumab was safe and well tolerated, and no AEs were reported. There was no elevation of either D-dimer or F1.2 levels post idarucizumab as compared to levels prior to infusion in any of the dose groups. Treatment-emergent ADAs occurred in 6 of 60 patients receiving idarucizumab. Conclusion: Idarucizumab infusion achieved immediate, complete and sustained reversal of dabigatran-associated anticoagulation in healthy male Japanese volunteers. Idarucizumab was safe and well tolerated with no procoagulant effects. Disclosures van Ryn:Boehringer Ingelheim: Employment. Yasaka:Sanofi: Research Funding; Nippon Boehringer Ingelheim: Other: received lecture fees (over 1 million Yen); Bristol-Myers Squibb: Other: received lecture fees (over 1 million Yen); Bayer Yakuhin: Other: received lecture fees (over 1 million Yen); Daiichi-Sankyo: Other: received lecture fees (over 1 million Yen). Harada:Boehringer Ingelheim: Employment. Taniguchi:Boehringer Ingelheim: Employment. Imazu:Boehringer Ingelheim: Employment. Norris:Boehringer Ingelheim: Employment. Gansser:Boehringer Ingelheim: Employment. Stangier:Boehringer Ingelheim: Employment.

Idarucizumab is a specific reversal agent that rapidly neutralizes dabigatran’s anticoagulant activity [(1–3)][1]. We investigated restoration of dabigatran anticoagulation 24 h after idarucizumab treatment and the safety and effectiveness of a second idarucizumab treatment. Six male and 6

Background Idarucizumab is a monoclonal antibody fragment that binds dabigatran with high affinity in a 1: 1 molar ratio. We investigated the safety, tolerability, and efficacy of increasing doses of idarucizumab for the reversal of anticoagulant effects of dabigatran in a two-part phase 1 study (rising-dose assessment and dose-finding, proof-of-concept investigation). Here we present the results of the proof-of-concept part of the study.Methods In this randomised, placebo-controlled, double-blind, proof-of-concept phase 1 study, we enrolled healthy volunteers (aged 18-45 years) with a body-mass index of 18.5-29.9 kg/m(2) into one of four dose groups at SGS Life Sciences Clinical Research Services, Belgium. Participants were randomly assigned within groups in a 3: 1 ratio to idarucizumab or placebo using a pseudorandom number generator and a supplied seed number. Participants and care providers were masked to treatment assignment. All participants received oral dabigatran etexilate 220 mg twice daily for 3 days and a final dose on day 4. Idarucizumab (1 g, 2 g, or 4 g 5-min infusion, or 5 g plus 2.5 g in two 5-min infusions given 1 h apart) was administered about 2 h after the final dabigatran etexilate dose. The primary endpoint was incidence of drug-related adverse events, analysed in all randomly assigned participants who received at least one dose of dabigatran etexilate. Reversal of diluted thrombin time (dTT), ecarin clotting time (ECT), activated partial thromboplastin time (aPTT), and thrombin time (TT) were secondary endpoints assessed by measuring the area under the effect curve from 2 h to 12 h (AUEC 2-12) after dabigatran etexilate ingestion on days 3 and 4. This trial is registered with ClinicalTrials.gov, number NCT01688830.Findings Between Feb 23, and Nov 29, 2013, 47 men completed this part of the study. 12 were enrolled into each of the 1 g, 2 g, or 5 g plus 2.5 g idarucizumab groups (nine to idarucizumab and three to placebo in each group), and 11 were enrolled into the 4 g idarucizumab group (eight to idarucizumab and three to placebo). Drug-related adverse events were all of mild intensity and reported in seven participants: one in the 1 g idarucizumab group (infusion site erythema and hot flushes), one in the 5 g plus 2.5 g idarucizumab group (epistaxis); one receiving placebo (infusion site haematoma), and four during dabigatran etexilate pretreatment (three haematuria and one epistaxis). Idarucizumab immediately and completely reversed dabigatran-induced anticoagulation in a dose-dependent manner; the mean ratio of day 4 AUEC 2-12 to day 3 AUEC 2-12 for dTT was 1.01 with placebo, 0.26 with 1 g idarucizumab (74% reduction), 0.06 with 2 g idarucizumab (94% reduction), 0.02 with 4 g idarucizumab (98% reduction), and 0.01 with 5 g plus 2.5 g idarucizumab (99% reduction). No serious or severe adverse events were reported, no adverse event led to discontinuation of treatment, and no clinically relevant difference in incidence of adverse events was noted between treatment groups.Interpretation These phase 1 results show that idarucizumab was associated with immediate, complete, and sustained reversal of dabigatran-induced anticoagulation in healthy men, and was well tolerated with no unexpected or clinically relevant safety concerns, supporting further testing. Further clinical studies are in progress.

Introduction: Dabigatran etexilate is an oral direct thrombin inhibitor. Although routine anticoagulation monitoring with dabigatran is not usually required, a simple and precise laboratory test to measure dabigatran concentrations in patient plasma may be useful in certain clinical circumstances, such as emergency situations. The HEMOCLOT (R) Thrombin Inhibitors assay has demonstrated accurate and precise determination of dabigatran concentrations within a range of 50-500 ng/ml. The objective of this study was to assess comparability of dabigatran concentrations determined by HEMOCLOT (R) and by liquid chromatography/tandem mass spectrometry (LC-MS/MS) in plasma samples from human volunteers with end-stage renal disease (ESRD) undergoing regular haemodialysis (HD) during a Phase I study.Materials and Methods: Overall, 304 plasma samples were obtained from seven ESRD patients in dabigatran steady-state for measurement by HEMOCLOT (R) (calibrated diluted thrombin time [dTT]) and by LC-MS/MS. Agreement of dabigatran concentrations was assessed by regression analysis and difference plots.Results: The measurements of calibration standards of the HEMOCLOT (R) assay showed excellent precision with coefficients of variation <5%. Accuracy determined by analysis of two quality control samples was 90% and 111%. HEMOCLOT (R)-derived dabigatran plasma concentrations paralleled those obtained by LC-MS/MS. The mean ratio of the LC-MS/MS and dTT-derived concentrations was 0.955 (67% limits of agreement: 0.771-1.18).Conclusions: The HEMOCLOT (R) Thrombin Inhibitors assay is suitable for measuring dabigatran plasma concentrations in volunteers with ESRD undergoing haemodialysis. The agreement between dabigatran concentrations determined by the HEMOCLOT (R) assay and the LC-MS/MS reference method met bioanalytical acceptance criteria. (C) 2015 Elsevier Ltd. All rights reserved.

Transporter gene knockout rat models are attracting increasing interest for mechanistic studies of new drugs as transporter substrates or inhibitors in vivo. However, limited data are available on the functional validity of such models at the blood-brain barrier. Therefore, the present study evaluated Mdr1a [P-glycoprotein (P-gp)], Bcrp, and combined Mdr1a/Bcrp knockout rat strains for the influence of P-gp and breast cancer resistance protein (BCRP) transport proteins on brain penetration of the selective test substrates [14C]WEB 2086 (3-[4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f][1,2,4]triazolo-[4,3-a][1,4]-diazepin-2-yl]-1-(4-morpholinyl)-1-propanon) for P-gp and dantrolene for BCRP. Brain-to-plasma concentration ratios (BPR) were measured after intravenous coinfusions of 5.5 µmol/kg per hour [14C]WEB 2086 and 2 µmol/kg per hour dantrolene for 2 hours in groups of knockout or wild-type rats. Compared with wild-type controls, mean BPR of [14C]WEB 2086 increased 8-fold in Mdr1a knockouts, 9.5-fold in double Mdr1a/Bcrp knockouts, and 7.3-fold in zosuquidar-treated wild-type rats, but was unchanged in Bcrp knockout rats. Mean BPR of dantrolene increased 3.3-fold in Bcrp knockouts and 3.9-fold in double Mdr1a/Bcrp knockouts compared with wild type, but was unchanged in the Mdr1a knockouts. The human intestinal CaCo-2 cell bidirectional transport system in vitro confirmed the in vivo finding that [14C]WEB 2086 is a substrate of P-gp but not of BCRP. Therefore, Mdr1a, Bcrp, and combined Mdr1a/Bcrp knockout rats provide functional absence of these efflux transporters at the blood-brain barrier and are a suitable model for mechanistic studies on the brain penetration of drug candidates.

Afatinib, an oral irreversible ErbB family blocker, undergoes minimal metabolism by non-enzyme-catalysed adduct formation with proteins or nucleophilic small molecules and is predominantly non-renally excreted via the entero-hepatic system. This trial assessed whether mild or moderate hepatic impairment influences the pharmacokinetics of afatinib.

Afatinib is a potent, irreversible, ErbB family blocker in clinical development for the treatment of advanced non-small cell lung cancer, metastatic head and neck cancer, and other solid tumours. As afatinib is a substrate for the P-glycoprotein (P-gp) pump transporter the three studies presented here investigated the pharmacokinetics of afatinib in the presence of a potent inhibitor (ritonavir) or inducer [rifampicin (rifampin)] of P-gp.

INTRODUCTION: The new oral anticoagulants are effective alternatives for warfarin but specific antidotes are not yet available for these agents to manage life-threatening bleeding or when emergency surgery is necessary. A specific antibody fragment (Fab) is being developed which binds dabigatran with high affinity and thereby prevents dabigatran inhibition of thrombin. For the first time in human volunteers, we determined whether equimolar doses of Fab would reverse the anticoagulant effects of dabigatran. METHODS: Safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of the Fab were investigated in a randomized, double-blind, placebo controlled study in 145 healthy male volunteers. In part I of the study, subjects received single rising i.v. doses of up to 8 g Fab. In part II, Fab doses of 1 g, 2 g and 4 g were administered as 5 min i.v. infusion in the presence of dabigatran (220 mg bid for 4 days). Concentrations of unbound dabigatran were determined as a measure of pharmacologically ac...

To investigate the pharmacokinetics, metabolism and tolerability of afatinib (BIBW 2992), an oral irreversible ErbB family blocker, in healthy male volunteers.

Abstract 1065 Poster Board I-87 Dabigatran etexilate is a prodrug, which is rapidly converted in vivo to the active moiety dabigatran, a potent, direct thrombin inhibitor. This drug has been evaluated as an alternative to oral vitamin K antagonists for sustained prevention of ischemic and hemorrhagic strokes in patients with atrial fibrillation. As with any anticoagulant, there are bleeding risks with its use. Thus, the adsorption of drug to activated charcoal to allow for potential neutralization in emergency situations was tested in vitro. Binding of dabigatran etexilate to activated charcoal in water simulates recent ingestion (2-3 hrs) of large amounts of dabigatran etexilate in the stomach fluid. Binding of dabigatran to activated charcoal in plasma simulates situations where dabigatran was absorbed after ingestion and present in high concentrations in plasma. The contents of 5, 10 and 20 capsules (150 mg/capsule) of dabigatran etexilate were suspended in 100 ml water (approx. stomach volume, pH 2.7, 2.5 and 2.4, respectively). Each suspension was divided in half. To one portion a freshly prepared activated charcoal suspension (125 mg/ml, Ultracarbon®, Merck) was added. Both suspensions (with and without charcoal) were filtered and dabigatran etexilate concentrations were assessed via HPLC. Levels of 8.3, 15.6 and 29.6 mg/ml dabigatran etexilate were recovered by HPLC in the untreated suspensions in water. In the charcoal-treated suspensions, the dabigatran etexilate peak was no longer detectable, this indicated that >99.9 % of dabigatran etexilate was adsorbed by the activated charcoal for all three tested concentrations. In the plasma experiments, dabigatran was added to a human plasma pool at concentrations of 470 and 940 ng/ml. The sample was then split, and active charcoal was added to half at the manufacturer's specified concentration (125 mg/ml), or 1:11 dilution of this. Dabigatran plasma levels were measured by a validated LC-MS/MS method. After adding dabigatran active substance to plasma, values of 394 ± 19.4 and 824 ± 39.3 ng/ml (mean ± SD) were obtained in untreated plasma. Addition of activated charcoal at both concentrations reduced levels of dabigatran to <1.01 ng/ml (i.e. close to or below lower limit of quantification of the assay). These preliminary in vitro studies demonstrate that the prodrug dabigatran etexilate, and the active moiety, dabigatran, bind activated charcoal and can be removed from water or plasma. Clinical implications may be that oral activated charcoal could be used to neutralise recent ingestion of overdose quantities of dabigatran etexilate before it is absorbed in the gut. In addition, dabigatran could theoretically be adsorbed from plasma via hemoperfusion over a charcoal filter. However, further testing in more clinically relevant models, is required before this can be recommended in patients. Disclosures: van Ryn: Boehringer Ingelheim Pharma GmbH & Co KG: Employment. Sieger:Boehringer Ingelheim Pharma GmbH & Co KG: Employment. Kink-Eiband:Boehringer Ingelheim Pharma GmbH & Co KG: Employment. Gansser:Boehringer Ingelheim Pharma GmbH & Co K: Employment. Clemens:Boehringer Ingelheim GmbH: Employment.

AIMS:The novel direct thrombin inhibitor (DTI), dabigatran etexilate (Boehringer Ingelheim Pharma GmbH & Co. KG), shows potential as an oral antithrombotic agent. Two double-blind, randomized trials were undertaken to investigate the pharmacokinetics (PK), pharmacodynamics (PD) and tolerability of orally administered dabigatran etexilate in healthy male subjects.METHODS:Dabigatran etexilate or placebo was administered orally at single doses of 10-400 mg (n = 40) or at multiple doses of 50-400 mg three times daily for 6 days (n = 40). Plasma and urine samples were collected over time to determine the PK profile of dabigatran. PD activity was assessed by its effects on blood coagulation parameters: activated partial thromboplastin time (aPTT), prothrombin time (PT), reported as international normalized ratio (INR), thrombin time (TT), and ecarin clotting time (ECT). All adverse events were recorded.RESULTS:Dabigatran etexilate was rapidly absorbed with peak plasma concentrations of dabigatran reached within 2 h of administration. This was followed by a rapid distribution/elimination phase and a terminal phase, with associated estimated half-lives of 8-10 h and 14-17 h with single and multiple dose administrations, respectively. Dabigatran exhibited linear PK characteristics with dose-proportional increases observed in maximum plasma concentration and area under the curve. Steady-state conditions were reached within 3 days with multiple dosing. The mean apparent volume of distribution during the terminal phase (V(z)/F) of 1860 l (range 1430-2400 l) and the apparent total clearance after oral administration (CL(tot)/F) of 2031 ml min(-1) (range 1480-2430), were dose independent. Time curves for aPTT, INR, TT and ECT paralleled plasma concentration-time curves with values increasing rapidly and in a dose-dependent manner. At the highest dose of 400 mg administered three times daily, maximum prolongations over baseline of 3.1 (aPTT), 3.5 (INR), 29 (TT) and 9.5-fold (ECT) were observed. Dabigatran underwent conjugation with glucuronic acid to form pharmacologically active conjugates that accounted for approximately 20% of total dabigatran in plasma. Overall, variability in PK parameters was low to moderate, with an average interindividual coefficient of variation (CV) of approximately 30% and variability in PD parameters was low, with CV < 10%. Of the four assays, TT and ECT exhibited the greatest sensitivity and precision within the anticipated therapeutic dose range. Bleeding events were few and were mild-to-moderate in intensity, occurring only in the higher, multiple dose groups.CONCLUSIONS:These data suggest that dabigatran etexilate is a promising novel oral DTI with predictable PK and PD characteristics and good tolerability. Further investigation of dabigatran etexilate for the treatment and prophylaxis of patients with arterial and venous thromboembolic disorders, acute coronary syndromes and other medical conditions is warranted.