Recommendation of mavacamten posology by model-based analyses in adults with obstructive hypertrophic cardiomyopathy.

Mavacamten is the first cardiac myosin inhibitor approved by the US Food and Drug Administration for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (HCM). The phase III EXPLORER-HCM (NCT03470545) study used a dose-titration scheme based on mavacamten exposure and echocardiographic assessment of Valsalva left ventricular outflow tract gradient (VLVOTg) and left ventricular ejection fraction (LVEF). Using population pharmacokinetic/exposure-response modeling and simulations of virtual patients, this in silico study evaluated alternative dose-titration regimens for mavacamten, including regimens that were guided by echocardiographic measures only. Mavacamten exposure-response models for VLVOTg (efficacy) and LVEF (safety) were developed using patient data from five clinical studies and characterized using nonlinear mixed-effects models. Simulations of five echocardiography-guided regimens were performed in virtual cohorts constructed based on either expected or equal population distributions of cytochrome P450 2C19 (CYP2C19) metabolizer phenotypes. Each regimen aimed to maximize the proportions of patients who achieved a VLVOTg below 30 mm Hg while maintaining LVEF above 50% over 40 weeks and 104 weeks, respectively. The exposure-response models successfully characterized mavacamten efficacy and safety parameters. Overall, the simulated regimen with the optimal benefit-risk profile across CYP2C19 phenotypes had steps for down-titration at weeks 4 and 8 (for VLVOTg <20 mm Hg), and up-titration at week 12 (for VLVOTg ≥30 mm Hg and LVEF ≥55%), and every 12 weeks thereafter. This simulation-optimized regimen is recommended in the mavacamten US prescribing information.

Effects of Omeprazole and Verapamil on the Pharmacokinetics, Safety, and Tolerability of Mavacamten: Two Drug-Drug Interaction Studies in Healthy Participants.

Two open-label, Phase 1 studies assessed the effects of omeprazole (a weak to moderate cytochrome P450 [CYP] 2C19 inhibitor) and verapamil (a moderate CYP3A4 inhibitor) on the pharmacokinetics, safety, and tolerability of mavacamten. In the omeprazole study, healthy participants received mavacamten 15 mg alone or with a 31-day course of omeprazole 20 mg once daily. In the verapamil study, healthy participants received mavacamten 25 mg alone or with a 28-day course of verapamil 240 mg once daily. In the omeprazole study, 27 of 29 randomized participants completed the study. Nine participants receiving mavacamten alone were normal metabolizers (NMs) of CYP2C19 substrates, and 6 were rapid metabolizers; 8 NMs and 6 rapid metabolizers received mavacamten + omeprazole. In both studies, mavacamten showed no safety signals and was generally well tolerated. Overall mavacamten exposure (area under the plasma concentration-time curve) increased by approximately 50% with omeprazole coadministration; maximum observed concentration (Cmax ), time to Cmax , and elimination half-life were not affected appreciably. In the verapamil study, 25 of 26 randomized participants received the study drug(s) and were included in the pharmacokinetic analyses; 24 completed the study. In the pharmacokinetic population, 12 participants received mavacamten alone (11 NMs, 1 poor metabolizer) and 13 received mavacamten + verapamil (7 NMs, 4 intermediate metabolizers, 2 poor metabolizers). Following verapamil coadministration in NMs and intermediate metabolizers, mavacamten area under the plasma concentration-time curve was minimally increased (by less than 20%), and Cmax was modestly increased (by 52%). These results suggest that mavacamten can be coadministered with weak CYP2C19 and moderate CYP3A4 inhibitors.

Physiologically Based Pharmacokinetic Modeling and Simulation of Mavacamten Exposure with Drug-Drug Interactions from CYP Inducers and Inhibitors by CYP2C19 Phenotype.

Mavacamten is a first-in-class, oral, selective, allosteric, reversible cardiac myosin inhibitor approved by the US Food and Drug Administration for the treatment of adults with symptomatic New York Heart Association functional class II-III obstructive hypertrophic cardiomyopathy. Mavacamten is metabolized in the liver, predominantly via cytochrome P450 (CYP) enzymes CYP2C19 (74%), CYP3A4 (18%), and CYP2C9 (8%). A physiologically-based pharmacokinetic (PBPK) model was developed using Simcyp version 19 (Certara, Princeton, NJ). Following model verification, the PBPK model was used to explore the effects of strong CYP3A4 and CYP2C19 inducers, and strong, moderate, and weak CYP2C19 and CYP3A4 inhibitors on mavacamten pharmacokinetics (PK) in a healthy population, with the effect of CYP2C19 phenotype predicted for poor, intermediate, normal, and ultrarapid metabolizers. The PBPK model met the acceptance criteria for all verification simulations (> 80% of model-predicted PK parameters within 2-fold of those observed clinically). A weak induction effect was predicted when mavacamten was administered with a strong CYP3A4 inducer in poor metabolizers. Moderate reductions in mavacamten exposure were predicted with a strong CYP2C19/CYP3A4 inducer in all CYP2C19 phenotypes. Except for the effect of strong CYP2C19 inhibitors on ultrarapid metabolizers, steady-state area under plasma concentration-time curve and maximum plasma concentration values were weakly affected (< 2-fold) or not affected (< 1.25-fold), regardless of CYP2C19 phenotype. In conclusion, a fit-for-purpose PBPK model was developed and verified, which accurately predicted the available clinical data and was used to simulate the potential impact of CYP induction and inhibition on mavacamten PKs, stratified by CYP2C19 phenotype.

Drug-Drug Interaction Potential of Mavacamten with Oral Contraceptives: Results from a Clinical Pharmacokinetic Study and a Physiologically Based Pharmacokinetic Model.

Mavacamten is a potential inducer of cytochrome P450 (CYP) 3A4 and, as such, could reduce the exposure of the active components of oral contraceptives, ethinyl estradiol (EE) and norethindrone (NOR), where CYP3A4 is involved in metabolism. This study assessed if repeat doses of mavacamten led to a drug-drug interaction with EE and/or NOR. This was an open-label study in healthy women. In Period 1, participants received 35 mcg of EE and 1 mg of NOR. In Period 2, participants received oral loading doses of mavacamten 25 mg on Days 1-2, 15 mg/day on Days 3-17, and 35 mcg of EE and 1 mg of NOR on Day 15. Plasma concentrations of mavacamten, EE, and NOR were obtained before dosing and up to 72 hours after dosing. For EE only, a physiologically based pharmacokinetic model was used to simulate mavacamten-mediated CYP3A4 induction with EE for various CYP2C19 phenotypes. In total, 13 women were enrolled (mean age, 38.9 [standard deviation, 9.65] years). After mavacamten administration, modest increases in area under the concentration-time curves were observed for both EE and NOR. The maximum concentrations and half-lives for EE and NOR were not affected by coadministration with mavacamten. Criteria for bioequivalence were met or nearly met for EE and NOR exposure with geometric mean ratios between 0.8 and 1.25. All adverse events were mild. The physiologically based pharmacokinetic model predicted a less than 15% decrease in EE exposure across CYP2C19 phenotypes. Coadministration of mavacamten at a therapeutically relevant dose with EE and NOR did not decrease the exposure to either EE or NOR to a level that may lead to reduced effectiveness.

Evaluation of safety, pharmacokinetics, and pharmacodynamics of apixaban in pediatric subjects at risk of venous or arterial thrombotic disorder.

Apixaban is an oral small-molecule, direct factor Xa (FXa) inhibitor approved in adults for treatment of deep vein thrombosis and pulmonary embolism, and for reducing risk of venous thromboembolism recurrence after initial anticoagulant therapy. This phase I study (NCT01707394) evaluated the pharmacokinetics (PKs), pharmacodynamics (PDs), and safety of apixaban in pediatric subjects (<18 years), enrolled by age group, at risk of venous or arterial thrombotic disorder. A single apixaban dose, targeting adult steady-state exposure with apixaban 2.5 mg, was administered using two pediatric formulations: 0.1 mg sprinkle capsule (age <28 days); 0.4 mg/ml solution (age 28 days to <18 years; dose range, 1.08-2.19 mg/m2 ). End points included safety, PKs, and anti-FXa activity. For PKs/PDs, four to six blood samples were collected ≤26 h postdosing. A population PK model was developed with data from adults and pediatric subjects. Apparent oral clearance (CL/F) included fixed maturation function based on published data. From January 2013 to June 2019, 49 pediatric subjects received apixaban. Most adverse events were mild/moderate, and the most common was pyrexia (n = 4/15). Apixaban CL/F and apparent central volume of distribution increased less than proportionally with body weight. Apixaban CL/F increased with age, reaching adult values in subjects aged 12 to <18 years. Maturation affected CL/F most notably in subjects aged <9 months. Plasma anti-FXa activity values were linearly related to apixaban concentrations, with no apparent age-related differences. Pediatric subjects tolerated single apixaban doses well. Study data and population PK model supported phase II/III pediatric trial dose selection.

Effects of rifampin on the pharmacokinetics and pharmacodynamics of milvexian, a potent, selective, oral small molecule factor XIa inhibitor.

Milvexian (BMS-986177/JNJ-70033093) is a potent, oral small molecule that inhibits the active form of factor XI with high affinity and selectivity. This study assessed the single-dose pharmacokinetic and pharmacodynamic properties of milvexian co-administered with rifampin, an organic anion transport protein (OATP) inhibitor and potent cytochrome P450 (CYP) 3A and P-glycoprotein (P-gp) inducer. In this open-label, nonrandomized, single-sequence study, healthy participants (N = 16) received single doses of milvexian on Day 1 (100 mg), milvexian and rifampin (600 mg) on Day 4, rifampin on Days 5-11, milvexian and rifampin on Day 12, and rifampin on Days 13-14. Pharmacokinetic data were summarized using descriptive statistics. Administration of milvexian, alone or in combination with rifampin, was generally safe and well tolerated. Single-dose co-administration of rifampin and milvexian demonstrated no meaningful changes in milvexian exposure versus milvexian alone (Cmax, 110%; AUC[0-T], 102%; AUC[INF], 101%). After multiple doses of rifampin and milvexian, peak and total milvexian exposure substantially decreased versus milvexian alone (Cmax, 22%; AUC[0-T], 15%; AUC[INF], 15%). Results were consistent with preclinical data, indicating that milvexian is a substrate for CYP3A4/5 and P-gp but not OATP. The implications of these results on the need for dose adjustment of milvexian will be further elucidated following the completion of phase 2 and 3 trials.Trial registration The study was registered with ClinicalTrials.gov (NCT02959060; submitted 7/11/2016, first posted 8/11/2016).

Performance Verification of CYP2C19 Enzyme Abundance Polymorphism Settings within the Simcyp Simulator v21.

Physiologically based pharmacokinetic (PBPK) modeling has a number of applications, including assessing drug−drug interactions (DDIs) in polymorphic populations, and should be iteratively refined as science progresses. The Simcyp Simulator is annually updated and version 21 included updates to hepatic and intestinal CYP2C19 enzyme abundance, including addition of intermediate and rapid metabolizer phenotypes and changes to the ultra-rapid metabolizer enzyme abundance, with implications for population clearance and DDI predictions. This work details verification of the updates with sensitive CYP2C19 substrates, omeprazole and lansoprazole, using available clinical data from literature. Multiple assessments were performed, including recovery of areas under the concentration-time curve (AUC) and Cmax from compiled datasets for each drug, recovery of victim DDI ratios with CYP2C19 and/or CYP3A4 inhibition and recovery of relative exposure between phenotypes. Simulated data were within respective acceptance criteria for >80% of omeprazole AUC values, >70% of lansoprazole AUC and Cmax, >60% of AUC and Cmax DDI ratios and >80% of exposure ratios between different phenotypes. Recovery of omeprazole Cmax was lower (>50−70% within 2-fold) and possibly attributed to the variety of formulations used in the clinical dataset. Overall, the results demonstrated that the updated data used to parameterize CYP2C19 phenotypes reasonably described the pharmacokinetics of omeprazole and lansoprazole in genotyped or phenotyped individuals.

Rationale and design of the AXIOMATIC-SSP phase II trial: Antithrombotic treatment with factor XIa inhibition to Optimize Management of Acute Thromboembolic events for Secondary Stroke Prevention.

BACKGROUND: Individuals with ischemic stroke or transient ischemic attack (TIA) have a high early risk of ischemic stroke despite dual antiplatelet therapy. The risk of ischemic stroke, and associated disability, represents a significant unmet clinical need. Genetic variants resulting in reduced factor XI levels are associated with reduced risk for ischemic stroke but are not associated with increased intracranial bleeding. Milvexian is an oral small-molecule inhibitor of FXIa that binds activated factor XI with high affinity and selectivity and may reduce the risk of stroke when added to antiplatelet drugs without significant bleeding. We aimed to evaluate the dose-response relationship of milvexian in participants treated with dual antiplatelets. METHODS: We began a phase II, double-blinded, randomized, placebo-controlled trial at 367 sites in 2019. Participants (N = 2366) with ischemic stroke (National Institutes of Health Stroke Scale score ≤7) or high-risk TIA (ABCD2 score ≥6) were randomized to 1 of 5 doses of milvexian or placebo for 90 days. Participants also received clopidogrel 75 mg daily for the first 21 days and aspirin 100 mg for 90 days. The efficacy endpoint was the composite of ischemic stroke or incident infarct on magnetic resonance imaging. Major bleeding, defined as type 3 or 5 bleeding according to the Bleeding Academic Research Consortium, was the safety endpoint. Participant follow-up will end in 2022. CONCLUSION: The AXIOMATIC-SSP trial will evaluate the dose-response of milvexian for ischemic stroke occurrence in participants with ischemic stroke or TIA.

Single-Dose Pharmacokinetics of Milvexian in Participants with Normal Renal Function and Participants with Moderate or Severe Renal Impairment.

OBJECTIVE: The aim of this study was to assess the effect of moderate or severe renal impairment on the pharmacokinetic (PK) properties of milvexian. METHODS: This open-label, parallel-group study assessed the PK, safety, and tolerability of a single oral 60 mg dose of milvexian in participants with normal renal function (n = 8; estimated glomerular filtration rate [eGFR] ≥ 90 mL/min/1.73 m2) and participants with moderate (n = 8; eGFR ≥ 30 to ≤ 59 mL/min/1.73 m2) or severe (n = 8; eGFR < 30 mL/min/1.73 m2) renal impairment. Regression analysis was performed using linear regression of log-transformed PK parameters versus eGFR. RESULTS: Milvexian was well tolerated, with no deaths, serious adverse events, or serious bleeding reported. The maximum milvexian concentration (Cmax) was similar for all groups. Based on a regression analysis of milvexian concentration versus eGFR, participants with eGFR values of 30 and 15 mL/min/1.73 m2, respectively, had area under the curve (AUC) values that were 41% and 54% greater than in participants with normal renal function. Median time to maximum concentration (Tmax) was similar for the three groups (4.5-5.0 h). The half-life increased for participants with moderate (18.0 h) or severe (17.7 h) renal impairment compared with those with normal renal function (13.8 h). CONCLUSION: A single dose of milvexian 60 mg was safe and well tolerated in participants with normal renal function and moderate or severe renal impairment. There was a similar increase in milvexian exposure between the moderate and severe renal groups. CLINICAL TRIALS REGISTRATION: This study was registered with ClinicalTrials.gov (NCT03196206, first posted 22 June 2017).

Effects of Itraconazole and Diltiazem on the Pharmacokinetics and Pharmacodynamics of Milvexian, A Factor XIa Inhibitor.

INTRODUCTION: Modulation of Factor XIa (FXIa) may provide a novel mechanism for systemic anticoagulation with the potential to improve the risk-benefit profile observed with existing anticoagulants through greater efficacy or a safer bleeding profile. This study assessed the effects of co-administration with strong and moderate CYP3A inhibitors itraconazole and diltiazem, respectively, on the pharmacokinetic and pharmacodynamic properties of milvexian, a Factor XIa inhibitor. METHODS: This was an open-label, non-randomized, two-period crossover study in healthy participants. In period 1, participants received a single oral dose of milvexian (30 mg) on day 1, followed by a washout on days 2 and 3. In period 2, participants received multiple oral doses of itraconazole (200 mg) or diltiazem (240 mg) with a single dose of milvexian. RESULTS: A total of 28 participants entered the treatment period. Following itraconazole co-administration, milvexian exposure was increased; AUC(0-T), AUC(INF), and C24 were 2.5-, 2.5-, and 3.8-fold higher, while mean Cmax was 28% higher versus milvexian alone. Diltiazem co-administration also increased milvexian exposure; AUC(0-T), AUC(INF), and C24 were 38, 38, and 64% higher, and mean Cmax was 9.6% higher versus milvexian alone. Prolongation of activated partial thromboplastin time was observed with milvexian in a concentration-dependent fashion irrespective of co-administration with itraconazole or diltiazem. Administration of a single dose of milvexian, alone or in combination with itraconazole or diltiazem, was generally safe and well tolerated; there were no deaths or serious adverse events. CONCLUSIONS: A moderate increase in milvexian exposure was observed following co-administration of itraconazole while a minimal increase was seen with diltiazem, consistent with the involvement of CYP3A metabolism and P-glycoprotein in drug absorption/elimination. Milvexian was generally safe and well tolerated in healthy participants. TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov (NCT02807909; submitted June 17, 2016).

Safety, pharmacokinetics, and pharmacodynamics of milvexian in healthy Japanese participants.

This randomized, double-blind, placebo-controlled, multiple ascending-dose study evaluated safety, tolerability, pharmacokinetics, and pharmacodynamics of multiple doses of milvexian, an oral small-molecule FXIa inhibitor, in healthy Japanese participants. Participants received oral milvexian daily under fasted (50 mg and 200 mg) or fed conditions (500 mg) or placebo over 14 days; 24 participants (8/cohort: 6 milvexian; 2 placebo) were planned. Due to an unblinding event, participants in one cohort (200 mg daily) were discontinued, and a second cohort enrolled; 32 participants were included in safety and pharmacodynamic analyses, and 24/32 in pharmacokinetic analyses. Milvexian up to 500 mg daily for 14 days was generally well tolerated, with no deaths, serious adverse events, or discontinuations due to adverse events. Milvexian exposure increased between 50-mg and 200-mg doses. Median Tmax was similar with 50-mg and 200-mg doses (2.5-3.0 h) and delayed under fed conditions (500 mg, 7.0-8.0 h). Median T1/2 was similar across doses (8.9-11.9 h). Multiple oral milvexian administrations resulted in concentration-related prolongation of aPTT and decreased FXI clotting activity. Milvexian was generally safe and well tolerated. The pharmacokinetic and pharmacodynamic profile of milvexian demonstrates suitability for further clinical development in Japanese participants.

Single-Dose Pharmacokinetics of Milvexian in Participants with Mild or Moderate Hepatic Impairment Compared with Healthy Participants.

BACKGROUND: Patients with hepatic impairment receiving antithrombotic agents metabolized primarily through the liver can be at risk for bleeding. Milvexian (BMS-986177/JNJ-70033093) is a small-molecule, active-site inhibitor of activated Factor XI (FXIa). Modulation of FXI may provide systemic anticoagulation without increased risk of clinically significant bleeding. OBJECTIVE: This open-label study evaluated the effects of mild or moderate hepatic impairment on the pharmacokinetics of milvexian to assess their impact on safety and dosing. METHODS: Single doses of milvexian 60 mg were administered to participants with mild hepatic impairment (n = 9), moderate hepatic impairment (n = 8), and normal hepatic function (n = 9). Healthy participants were matched to participants with hepatic impairment by body weight, age, and sex. Analysis of variance was performed on natural log-transformed milvexian exposure parameters, with hepatic function group as a fixed effect. RESULTS: Single doses of milvexian 60 mg were generally well tolerated, with no serious adverse events (AEs), bleeding AEs, or discontinuations due to AEs. Geometric mean ratios (90% confidence interval) for total milvexian maximum observed plasma concentration and area under the plasma concentration-time curve from time zero extrapolated to infinite time were 1.180 (0.735-1.895) and 1.168 (0.725-1.882), respectively, for mild hepatic impairment versus normal hepatic function and 1.140 (0.699-1.857) and 0.996 (0.609-1.628), respectively, for moderate hepatic impairment versus normal hepatic function. Across groups, milvexian exposure-related increases were observed for activated partial thromboplastin time. CONCLUSION: Milvexian was well tolerated in participants with normal, mildly impaired, and moderately impaired hepatic function. Observed pharmacokinetic changes suggest it is unlikely that dose adjustments will be necessary in patients with mild or moderate hepatic impairment. Clinical Trial RegistrationClinicaltrials.gov identifier: NCT02982707.

First-in-human study of milvexian, an oral, direct, small molecule factor XIa inhibitor.

Milvexian (BMS-986177/JNJ-70033093) is a small molecule, active-site inhibitor of factor XIa (FXIa) being developed to prevent and treat thrombotic events. The safety, tolerability, pharmacokinetics (PKs), and pharmacodynamics (PDs) of milvexian were assessed in a two-part, double-blind, placebo-controlled, sequential single ascending dose (SAD) and multiple ascending dose (MAD) study in healthy adults. Participants in SAD panels (6 panels of 8 participants; n = 48) were randomized (3:1) to receive milvexian (4, 20, 60, 200, 300, or 500 mg) or placebo. The 200- and 500-mg panels investigated the pharmacokinetic impact of a high-fat meal. Participants in MAD panels (7 panels of 8 participants; n = 56) were randomized (3:1) to receive milvexian (once- or twice-daily) or placebo for 14 days. All milvexian dosing regimens were safe and well-tolerated, with only mild treatment-emergent adverse events and no clinically significant bleeding events. In SAD panels, maximum milvexian plasma concentration occurred 3 h postdose in all fasted panels. The terminal half-life (T1/2 ) ranged from 8.3 to 13.8 h. In fasted panels from 20 to 200 mg, absorption was dose-proportional; results at higher doses (300 and 500 mg) were consistent with saturable absorption. Food increased milvexian bioavailability in a dose-dependent fashion. In MAD panels, steady-state milvexian plasma concentration was reached within 3 and 6 dosing days with once- and twice-daily dosing, respectively. Renal excretion was less than 20% in all panels. Prolongation of activated partial thromboplastin time was observed and was directly related to drug exposure. These results suggest that the safety, tolerability, PK, and PD properties of milvexian are suitable for further clinical development.

Antithrombotic Effects of Combined PAR (Protease-Activated Receptor)-4 Antagonism and Factor Xa Inhibition.

OBJECTIVE: PAR (protease-activated receptor)-4 antagonism has antiplatelet effects under conditions of high shear stress. We aimed to establish whether PAR4 antagonism had additive antithrombotic activity in the presence of factor Xa inhibition in an ex vivo model of acute arterial injury. Approach and Results: Fifteen healthy volunteers (29±6 years, 7 women) completed a phase zero double-blind randomized controlled crossover trial. Ex vivo platelet activation, platelet aggregation, and thrombus formation were measured following blood perfusion of low shear and high shear stress chambers. Upstream of the chambers, extracorporeal blood was admixed with (1) vehicle, (2) low-dose apixaban (20 ng/mL), (3) high-dose apixaban (80 ng/mL), (4) BMS-986141 (400 ng/mL), (5) BMS-968141 and low-dose apixaban, or (6) BMS-968141 and high-dose apixaban in 6 sequential studies performed in random order. Compared with vehicle, BMS-986141 demonstrated selective inhibition of PAR4-AP (agonist peptide)-stimulated platelet aggregation, platelet-monocyte aggregates, and P-selectin expression (P≤0.01 for all). Total thrombus area was reduced under both low shear and high shear stress conditions for all drug infusions (P<0.0001 for all versus vehicle). BMS-968141 reduced total (≤44.4%) and platelet-rich (≤39.3%) thrombus area, whereas apixaban reduced total (≤42.9%) and fibrin-rich (≤31.6%) thrombus area. Combination of BMS-986141 with apixaban caused a further modest reduction in total thrombus area (9.6%-12.4%), especially under conditions of high shear stress (P≤0.027). CONCLUSIONS: In the presence of factor Xa inhibition, PAR4 antagonism with BMS-986141 further reduces thrombus formation, especially under conditions of high shear stress. This suggests the potential for additive efficacy of combination PAR4 antagonism and factor Xa inhibition in the prevention of atherothrombotic events.

Inability of Current Dosing to Achieve Carboplatin Therapeutic Targets in People with Advanced Non-Small Cell Lung Cancer: Impact of Systemic Inflammation on Carboplatin Exposure and Clinical Outcomes.

BACKGROUND: The presence of elevated systemic inflammation in people with advanced non-small cell lung cancer (NSCLC) is associated with significantly shorter survival following carboplatin-based chemotherapy. OBJECTIVE: This study investigated whether novel factors, such as systemic inflammation [platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR)], impact carboplatin pharmacokinetics and drug utilisation. The study also examined the ability of current and alternate dosing regimens to meet therapeutic targets. METHODS: Seventy-two people with advanced NSCLC treated with carboplatin-based (460-1050 mg) doublet chemotherapy were recruited and pharmacokinetic data (n = 61) were analysed using non-linear mixed modelling. Covariate analysis was performed to investigate the impact of standard and novel patient characteristics of carboplatin pharmacokinetics. A Monte Carlo simulation of 100,000 representative NSCLC patients evaluated the ability of the Calvert formula and novel dosing strategies to achieve the targeted therapeutic range. The associations between systemic inflammation and chemotherapy drug utilisation (cycles received, relative dose intensity (RDI) and second-line uptake) and clinical endpoints were also investigated in the pharmacokinetic cohort, and two independent cohorts of people with advanced NSCLC from the Chemotherapy Dosing in Cancer-Related Inflammation (CDCRI) database that were administered carboplatin-paclitaxel (n = 37) or carboplatin-gemcitabine (n = 358). RESULTS: In all cohorts, 25-53% of people had elevated systemic inflammation (NLR > 5 or PLR > 300). In the pharmacokinetic cohort, no patients achieved the desired therapeutic target of carboplatin. Carboplatin exposure was related to renal function, as estimated using the Cockcroft-Gault formula, albumin and inflammation (NLR). In the pharmacokinetic cohort, increasing carboplatin area under the curve (AUC) correlated with greater reductions in red blood cells and haemoglobin. In this cohort, the average measured AUC of partial responders was 2.4 mg·min/mL. Also in the pharmacokinetic cohort, only 12% of people with an NLR > 5 received four or more cycles of chemotherapy, compared with 62% of patients with an NLR ≤ 5 (p < 0.001). For people in the CDCRI cohort receiving carboplatin-gemcitabine, those with an NLR > 5 also received less cycles (four or more cycles, 41% vs. 60%; p < 0.01) as well as less second-line chemotherapy (46% vs. 60%; p = 0.02) compared with patients without inflammation. People in the pharmacokinetic cohort with an NLR > 5 had 12 months less median survival compared with people with an NLR ≤ 5 (6.5 vs. 18 months; p = 0.08). Similarly, overall survival was significantly shortened in people in the CDCRI cohort receiving carboplatin-gemcitabine with an NLR > 5 compared with those with an NLR ≤ 5 (7 vs. 12 months; p < 0.001), and Cox regression analysis showed a 1.5-fold (1.3-2.1; p < 0.001) increased hazard of death associated with the increased systemic inflammation. Simulations of the newly developed model-based and Calvert dosing assessed the ability to reach this study's proposed actual target AUC of 2.2-2.6 mg·min/mL. These showed current Calvert dosing was predicted to result in substantial overexposure in patients with high systemic inflammation. The newly developed model showed equivalent levels of carboplatin therapeutic target achievement across the spectrum of inflammation observed in the lung cancer population. CONCLUSION: An alternate model-based dosing strategy for carboplatin was developed and is predicted to result in consistent drug exposure across the population and improve attainment of therapeutic targets. Further studies of this new model are warranted in people with advanced NSCLC.

Phase I study of single-dose pharmacokinetics and pharmacodynamics of belatacept in adolescent kidney transplant recipients.

Belatacept is an intravenously infused selective T cell costimulation blocker approved for preventing organ rejection in renal transplant recipients aged ≥18 years. This phase I trial examined the pharmacokinetics and pharmacodynamics (percentage CD86 receptor occupancy [%CD86RO]) of a single dose of belatacept (7.5 mg/kg) administered to kidney transplant recipients aged 12-17 years receiving a stable calcineurin inhibitor-based immunosuppressive regimen. Nine adolescents (mean age 15.1 years) who were seropositive for Epstein-Barr virus were enrolled; all completed the 6-month study. Pharmacokinetics suggested relatively low variability of exposure (coefficients of variation for maximum observed serum concentration [Cmax ] and area under the serum concentration-time curve from time zero extrapolated to infinity [AUC0-INF ] were 20% and 25%, respectively). Mean half-life (T1/2 ) occurred 7.2 days postinfusion. Belatacept total body clearance was 0.48 mL/h/kg, and volume of distribution at steady-state (Vss ) was low at 0.09 L/kg. Compared with historical data from healthy adult volunteers administered a single dose of belatacept 10 mg/kg and adult kidney transplant recipients administered multiple doses of belatacept 5 mg/kg, pharmacokinetic values for adolescents were similar, indicating consistency across adolescent and adult populations. Mean %CD86RO increased with increasing belatacept concentration, indicating a direct relationship between pharmacokinetics and pharmacodynamics. Four patients reported 7 serious adverse events; none was considered related to belatacept. These data will inform belatacept dose selection in future studies of adolescent kidney transplant recipients.

Further Studies to Support the Use of Coproporphyrin I and III as Novel Clinical Biomarkers for Evaluating the Potential for Organic Anion Transporting Polypeptide 1B1 and OATP1B3 Inhibition.

In a recent study, limited to South Asian Indian subjects (n = 12), coproporphyrin (CP) I and CPIII demonstrated properties appropriate for an organic anion-transporting polypeptide (OATP) 1B endogenous probe. The current studies were conducted in healthy volunteers of mixed ethnicities, including black, white, and Hispanic subjects, to better understand the utility of these biomarkers in broader populations. After oral administration with 600 mg rifampin, AUC(0-24h) values were 2.8-, 3.7-, and 3.6-fold higher than predose levels for CPI and 2.6-, 3.1-, and 2.4-fold higher for CPIII, for the three populations, respectively. These changes in response to rifampin were consistent with previous results. The sensitivity toward OATP1B inhibition was also investigated by evaluating changes of plasma CP levels in the presence of diltiazem and itraconazole [administered as part of an unrelated drug-drug interaction (DDI) investigation], two compounds that were predicted to have minimal inhibitory effect on OATP1B. Administration of diltiazem and itraconazole did not increase plasma CPI and CPIII concentrations relative to prestudy levels, in agreement with predictions from in vitro parameters. Additionally, the basal CP concentrations in subjects with SLCO1B1 c.521TT genotype were comparable to those with SLCO1B1 c.521TC genotype, similar to studies with probe substrates. However, subjects with SLCO1B1 c.388AG and c.388GG genotypes (i.e., increased OATP1B1 transport activity for certain substrates) had lower concentrations of CPI than those with SLCO1B1 c.388AA. Collectively, these findings provide further evidence supporting the translational value of CPI and CPIII as suitable endogenous clinical probes to gauge OATP1B activity and potential for OATP1B-mediated DDIs.

First-in-human study to assess the safety, pharmacokinetics and pharmacodynamics of BMS-962212, a direct, reversible, small molecule factor XIa inhibitor in non-Japanese and Japanese healthy subjects.

AIMS: The aims of the present study were to assess the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of BMS-962212, a first-in-class factor XIa inhibitor, in Japanese and non-Japanese healthy subjects. METHODS: This was a randomized, placebo-controlled, double-blind, sequential, ascending-dose study of 2-h (part A) and 5-day (part B) intravenous (IV) infusions of BMS-962212. Part A used four doses (1.5, 4, 10 and 25 mg h-1 ) of BMS-962212 or placebo in a 6:2 ratio per dose. Part B used four doses (1, 3, 9 and 20 mg h-1 ) enrolling Japanese (n = 4 active, n = 1 placebo) and non-Japanese (n = 4 active, n = 1 placebo) subjects per dose. The PK, PD, safety and tolerability were assessed throughout the study. RESULTS: BMS-962212 was well tolerated; there were no signs of bleeding, and adverse events were mild. In parts A and B, BMS-962212 demonstrated dose proportionality. The mean half-life in parts A and B ranged from 2.04 to 4.94 h and 6.22 to 8.65 h, respectively. Exposure-dependent changes were observed in the PD parameters, activated partial thromboplastin time (aPTT) and factor XI clotting activity (FXI:C). The maximum mean aPTT and FXI:C change from baseline at 20 mg h-1 in part B was 92% and 90%, respectively. No difference was observed in weight-corrected steady-state concentrations, aPTT or FXI:C between Japanese and non-Japanese subjects (P > 0.05). CONCLUSION: BMS-962212 has tolerability, PK and PD properties suitable for investigational use as an acute antithrombotic agent in Japanese or non-Japanese subjects.

Prediction of olanzapine exposure in individual patients using physiologically based pharmacokinetic modelling and simulation.

AIM: The aim of the present study was to predict olanzapine (OLZ) exposure in individual patients using physiologically based pharmacokinetic modelling and simulation (PBPK M&S). METHODS: A 'bottom-up' PBPK model for OLZ was constructed in Simcyp® (V14.1) and validated against pharmacokinetic studies and data from therapeutic drug monitoring (TDM). The physiological, demographic and genetic attributes of the 'healthy volunteer population' file in Simcyp® were then individualized to create 'virtual twins' of 14 patients. The predicted systemic exposure of OLZ in virtual twins was compared with measured concentration in corresponding patients. Predicted exposures were used to calculate a hypothetical decrease in exposure variability after OLZ dose adjustment. RESULTS: The pharmacokinetic parameters of OLZ from single-dose studies were accurately predicted in healthy Caucasians [mean-fold errors (MFEs) ranged from 0.68 to 1.14], healthy Chinese (MFEs 0.82 to 1.18) and geriatric Caucasians (MFEs 0.55 to 1.30). Cumulative frequency plots of trough OLZ concentration were comparable between the virtual population and patients in a TDM database. After creating virtual twins in Simcyp®, the R2 values for predicted vs. observed trough OLZ concentrations were 0.833 for the full cohort of 14 patients and 0.884 for the 7 patients who had additional cytochrome P450 2C8 genotyping. The variability in OLZ exposure following hypothetical dose adjustment guided by PBPK M&S was twofold lower compared with a fixed-dose regimen - coefficient of variation values were 0.18 and 0.37, respectively. CONCLUSIONS: Olanzapine exposure in individual patients was predicted using PBPK M&S. Repurposing of available PBPK M&S platforms is an option for model-informed precision dosing and requires further study to examine clinical potential.

Prediction of plasma caffeine concentrations in young adolescents following ingestion of caffeinated energy drinks: a Monte Carlo simulation.

The fast-growing consumption of caffeinated energy drinks (CEDs) is linked to increasing reports of caffeine intoxication in adolescents. There is limited data available regarding plasma caffeine concentrations in this population after CED intake and the potential implications for caffeine-related toxicity. This study was an in silico population pharmacokinetic analysis of caffeine. Population pharmacokinetic model of oral caffeine was derived from a previous study of healthy male volunteers. Maximal plasma caffeine concentration (C max) profiles following ingestion of one or two servings of popular CEDs were predicted using Monte Carlo simulation and available population body weight data of 10-15-year-old Korean adolescents. Caffeine C max values were positively correlated with the amount of caffeine ingested in CEDs and negatively correlated with body weight. The median (range) C max profiles varied from a low of 1.2 (0.5-2.6) mg/L to a concentration that is potentially associated with harmful caffeine-related effects of 25.4 (8.1-55.6) mg/L. A subgroup of female 10-11-year-old subjects exhibited the highest caffeine exposure profiles. CONCLUSION: These data indicate that CED ingestion can increase the risk of serious caffeine intoxication in young adolescents, particularly those with low body mass. WHAT IS KNOWN: • Excessive consumption of caffeine can lead to serious caffeine intoxication. • The risk of potential harmful caffeine intoxication after ingestion of caffeinated energy drinks (CED) has not been adequately evaluated in adolescents. WHAT IS NEW: • Predicted maximal plasma caffeine concentration profiles of adolescents with lower body weights showed an overlap with the ingested caffeine concentrations obtained from documented fatalities. • The present simulation-based pharmacokinetic analysis demonstrates that CED ingestion could lead to potentially serious caffeine intoxication in this cohort.