Population pharmacokinetics of naloxegol in a population of 1247 healthy subjects and patients

Population Pharmacokinetics of Naloxegol in Pediatric Subjects Receiving Opioids

The pharmacokinetics (PK) of naloxegol were characterized in pediatric subjects, aged 6 months or older to less than 18 years who either have or are at risk of developing opioid-induced constipation following single dose administration. Subjects grouped as aged 12 years or older to less than 18 years, 6 months or older to less than 12 years, and 6 months or older to less than 6 years, received a single oral dose of naloxegol at doses that were estimated to achieve plasma exposures comparable to adult 12.5- or 25-mg doses. Intensive and sparse plasma naloxegol samples were collected to assess naloxegol concentrations. Data were combined with previously collected adult PK data and used to estimate PK parameters using population PK analyses. Naloxegol PK was described using a 2-compartment model with Weibull-type absorption. Neither age nor body weight was identified as a significant covariate indicating similar PK properties in adult and pediatric subjects. PK estimates in the youngest age group were approximately 80% less than those in adults (12.5-mg equivalent dose). Exposures in the other pediatric groups were similar to those in adult equivalent doses. The PK of naloxegol were characterized as linear over the dose range, with no clinically significant covariates and comparable PK characteristics in adults and pediatric subjects aged 6 months or older.

Insights into the Use of Peripherally Acting μ-Opioid Receptor Antagonists (PAMORAs) in Oncologic Patients: from Scientific Evidence to Real Clinical Practice

OPINION STATEMENT

Management of chronic pain is crucial to improve the quality of life of cancer and palliative care patients. Opioid-based treatments used to control pain can be prolonged over time. Unfortunately, constipation is one of the most disturbing adverse effects of long-term use of opioids. Opioid-induced constipation (OIC) occurs when opioids bind to the specific receptors present in the gastrointestinal (GI) tract, and can affect any patients receiving chronic opioid therapy, including cancer patients. The limited efficacy of laxatives to treat OIC symptoms prompted the search for new therapeutic strategies. Peripherally acting μ-opioid receptor antagonists (PAMORAs) have recently emerged as new effective drugs for OIC management due to their specific binding to enteric μ-receptors. Little information is available on the use of PAMORAs in real-life practice for OIC treatment in cancer patients. In this paper, a panel of experts specializing in cancer and palliative care pools their clinical experience with PAMORAs in cancer patients presenting OIC and highlights the importance of timing and choice of therapy in achieving prompt OIC management and benefitting patients.

Naloxegol rescue with methylnaltrexone highly effective

Opioid-induced constipation (OIC) is common and can significantly affect quality of life. Naloxegol and methylnaltrexone are peripherally acting µ-opioid receptor antagonists (PAMORAs) which are effective for the management of OIC. We report on a case in the palliative care setting where a patient with established OIC had an inadequate response to naloxegol but an effective and immediate response to methylnaltrexone at the dose recommended for her weight. This is the first reported case of two PAMORAs used concomitantly.

Population Pharmacokinetics and Dosage Optimization of Linezolid in Patients with Liver Dysfunction

Linezolid is the first synthetic oxazolidone agent to treat infections caused by Gram-positive pathogens. Infected patients with liver dysfunction (LD) are more likely to suffer from adverse reactions, such as thrombocytopenia, when standard-dose linezolid is used than patients with LD who did not use linezolid. Currently, pharmacokinetics data of linezolid in patients with LD are limited. This study aimed to characterize pharmacokinetics parameters of linezolid in patients with LD, identify the factors influencing the pharmacokinetics, and propose an optimal dosage regimen. We conducted a prospective study and established a population pharmacokinetics model with the Phoenix NLME software. The final model was evaluated by goodness-of-fit plots, bootstrap analysis, and prediction corrected-visual predictive check. A total of 163 concentration samples from 45 patients with LD were adequately described by a one-compartment model with first-order elimination along with prothrombin activity (PTA) and creatinine clearance as significant covariates. Linezolid clearance (CL) was 2.68 liters/h (95% confidence interval [CI], 2.34 to 3.03 liters/h); the volume of distribution (V) was 58.34 liters (95% CI, 48.00 to 68.68 liters). Model-based simulation indicated that the conventional dose was at risk for overexposure in patients with LD or severe renal dysfunction; reduced dosage (300 mg/12 h) would be appropriate to achieve safe (minimum steady-state concentration [C _min,ss] at 2 to 8 μg/ml) and effective targets (the ratio of area under the concentration-time curve from 0 to 24 h [AUC_0-24] at steady state to MIC, 80 to 100). In addition, for patients with severe LD (PTA, ≤20%), the dosage (400 mg/24 h) was sufficient at an MIC of ≤2 μg/ml. This study recommended therapeutic drug monitoring for patients with LD. (This study has been registered in the Chinese Clinical Trial Registry under no. ChiCTR1900022118.).

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Optimal designs for regional bridging studies using the Bayesian power prior method

As described in the ICH E5 guidelines, a bridging study is an additional study executed in a new geographical region or subpopulation to link or "build a bridge" from global clinical trial outcomes to the new region. The regulatory and scientific goals of a bridging study is to evaluate potential subpopulation differences while minimizing duplication of studies and meeting unmet medical needs expeditiously. Use of historical data (borrowing) from global studies is an attractive approach to meet these conflicting goals. Here, we propose a practical and relevant approach to guide the optimal borrowing rate (percent of subjects in earlier studies) and the number of subjects in the new regional bridging study. We address the limitations in global/regional exchangeability through use of a Bayesian power prior method and then optimize bridging study design with a return on investment viewpoint. The method is demonstrated using clinical data from global and Japanese trials in dapagliflozin for type 2 diabetes.

Clinical Overview and Considerations for the Management of Opioid-induced Constipation in Patients With Chronic Noncancer Pain

OBJECTIVES

Opioid analgesics may be associated with chronic adverse effects, such as opioid-induced constipation (OIC). Available and emerging prescription medications for OIC in patients with chronic noncancer pain are described, including concerns and challenges associated with OIC management.

METHODS

Narrative review.

RESULTS

OIC is characterized by a change in bowel habits and defecation patterns that occurs when initiating opioid therapy and is associated with reduced bowel frequency, straining, sensation of incomplete evacuation, and/or patient distress related to bowel habits. Prescription medications are indicated when OIC persists despite conservative approaches (eg, increased fiber and fluid intake, exercise, over-the-counter laxatives and stool softeners). Phase 3 studies have demonstrated the efficacy of peripherally acting µ-opioid receptor antagonists (PAMORA; methylnaltrexone, naloxegol, naldemedine), and a chloride channel activator (lubiprostone) for improving OIC in patients with chronic noncancer pain. Although head-to-head studies are lacking, a meta-analysis demonstrated that μ-opioid receptor antagonists were more effective than placebo for the treatment of OIC. The most common adverse effects associated with prescription medications for OIC are gastrointestinal related (eg, nausea, diarrhea, abdominal pain, or distention), with most being mild or moderate in severity. Therapy currently in development for OIC includes the PAMORA axelopran.

DISCUSSION

Health care providers should be aware of this complication in patients receiving opioids and should monitor and address constipation-related symptoms to optimize pain management and improve patient quality of life.

Population Pharmacokinetic Modeling With Enterohepatic Circulation for AZD3241 in Healthy Subjects and Patients With Multiple System Atrophy

AZD3241 is a potent and selective myeloperoxidase inhibitor potentially for the treatment of a number of neurodegenerative disorders, including multiple system atrophy (MSA). The objectives of this work were to develop a population pharmacokinetic (PopPK) model for AZD3241 and to investigate the correlation between AZD3241 exposure and myeloperoxidase inhibition. The PopPK model was developed using AZD3241 data from one phase 1 study in healthy subjects and one phase 2 study in patients with MSA. A one-compartment model incorporating a gallbladder compartment for enterohepatic circulation, sequential zero-first order absorption, and first-order elimination adequately described the AZD3241 concentration profiles. The apparent clearance and central volume of distribution were 63.1 L/h (interindividual variability: 34.8%) and 121.9 L (interindividual variability: 44.0%), respectively. The enterohepatic circulation model reasonably captured the second peak of AZD3241, and high-fat food increased the absorption rate by 69%. A linear regression model was applied to describe the relationship between AZD3241 exposure and percentage change from baseline in myeloperoxidase-specific activity. The developed PopPK model was consistent with known pharmacokinetic characteristics of AZD3241. This model can be used to estimate AZD3241 exposure in patients with MSA and could be applied to future pharmacokinetic-pharmacodynamic analyses of AZD3241 in clinical development.

Clinical Pharmacokinetics and Pharmacodynamics of Naloxegol, a Peripherally Acting µ-Opioid Receptor Antagonist

Naloxegol is a peripherally acting µ-opioid receptor antagonist approved for use as an orally administered tablet (therapeutic doses of 12.5 and 25 mg) for the treatment of opioid-induced constipation. Over a wide dose range (i.e. single supratherapeutic doses up to 1000 mg in healthy volunteers), the pharmacokinetic properties of naloxegol appear to be time- and dose-independent. Naloxegol is rapidly absorbed, with mean time to maximum plasma concentration of <2 h. Following once-daily administration, steady state is achieved within 2-3 days and minimal accumulation is observed. The primary route of naloxegol elimination is via hepatic metabolism, with renal excretion playing a minimal role. In clinical studies, six metabolites were found in feces, urine or plasma, none of which have been identified as unique or disproportionate human metabolites. The major plasma circulating species is naloxegol. There are small effects of mild and moderate renal impairment, age, race, and body mass index on the systemic exposure of naloxegol; however, gender has no effect on the pharmacokinetics of this agent. Naloxegol is a sensitive substrate of cytochrome P450 (CYP) 3A4 and its exposure can be significantly altered by strong or moderate CYP3A modulators. Food increases the bioavailability of naloxegol, and the relative bioavailability of the tablet formulation was not limited by dissolution. Naloxegol in the dose range of 8-125 mg can antagonize morphine-induced peripheral effects without impacting the effect of morphine on the central nervous system, consistent with a peripheral mode of action.

Population Exposure-Response Modeling Supported Selection of Naloxegol Doses in Phase III Studies in Patients With Opioid-Induced Constipation

Naloxegol is approved for the treatment of opioid‐induced constipation (OIC) in adults with chronic noncancer pain. Population exposure‐response models were developed using data from a phase II study comprising 185 adults with OIC. The weekly probability of response defined as having ≥3/week spontaneous bowel movements (SBMs) and ≥1 SBM/week increase over baseline was characterized by a longitudinal mixed‐effects logistic regression dose‐response model, and the probability of time to discontinuation was modeled with a Weibull distribution function. The predicted probability of SBM in a given week increased with increasing naloxegol dose. The model predicted that 12.5, 25, and 37.5 mg doses would produce median response rates of 40%, 50%, and 60%, and dropout rates of 13.3%, 16.7%, and 23.3%, respectively. The large overlap of predicted difference of the response rate between placebo and the 25 or 37.5 mg doses suggested little utility of using a 37.5 mg dose in phase III studies.

Integrin-targeted nano-sized polymeric systems for paclitaxel conjugation: a comparative study

The generation of rationally designed polymer therapeutics via the conjugation of low molecular weight anti-cancer drugs to water-soluble polymeric nanocarriers aims to improve the therapeutic index. Here, we focus on applying polymer therapeutics to target two cell compartments simultaneously - tumour cells and angiogenic endothelial cells. Comparing different polymeric backbones carrying the same therapeutic agent and targeting moiety may shed light on any correlation between the choice of polymer and the anti-cancer activity of the conjugate. Here, we compared three paclitaxel (PTX)-bound conjugates with poly-l-glutamic acid (PGA, 4.9 mol%), 2-hydroxypropylmethacrylamide (HPMA, 1.2 mol%) copolymer, or polyethyleneglycol (PEG, 1:1 conjugate). PGA and HPMA copolymers are multivalent polymers that allow the conjugation of multiple compounds within the same polymer backbone, while PEG is a bivalent commercially available Food and Drug Administration (FDA)-approved polymer. We further conjugated PGA-PTX and PEG-PTX with the integrin α_vβ₃-targeting moiety RGD (5.5 mol% and 1:1 conjugate, respectively). We based our selection on the overexpression of integrin α_vβ₃ on angiogenic endothelial cells and several types of cancer cells. Our findings suggest that the polymer structure has major effect on the conjugate's activity on different tumour compartments. A multivalent PGA-PTX-E-[c(RGDfK)₂] conjugate displayed a stronger inhibitory effect on the endothelial compartment, showing a 50% inhibition of the migration of human umbilical vein endothelial cell cells, while a PTX-PEG-E-[c(RGDfK)₂] conjugate possessed enhanced anti-cancer activity on MDA-MB-231 tumour cells (IC₅₀ = 20 nM versus IC₅₀ 300 nM for the PGA conjugate).

Population Pharmacokinetics of Tobramycin Inhalation Solution in Pediatric Patients With Cystic Fibrosis

Tobramycin inhalation solution given as a twice daily inhalation of nebulized aerosols of 300 mg is approved for the treatment of Pseudomonas aeruginosa infection in cystic fibrosis patients over 6 years of age. To investigate tobramycin pharmacokinetics (PK) after inhalation of tobramycin in pediatric cystic fibrosis patients below 7 years, a population PK approach was used to evaluate tobramycin PK data in patients 6 months to 44 years of age from 4 clinical studies. The final model used a 2-compartmental, first-order absorption model with effect of body mass index on the apparent central volume of distribution. Relative bioavailability in patients between 6 months and 7 years increased with age by a linear relationship, and was modeled as a ratio to that of patients over 7 years. Simulation showed that steady-state concentrations of tobramycin are lower in pediatric patients 6 months to 6 years than those in patients over 6 years. However, systemic exposure is not predictive of clinical efficacy due to direct dosing at the infection site. P aeruginosa eradication rate and safety profile in patients less than 7 years of age were similar to patients older than 6 years; therefore, no dose adjustment is warranted in the younger pediatric patients.

Pharmacometric Modeling of Naloxegol Efficacy and Safety: Impact on Dose and Label

Naloxegol is a peripherally acting μ-opioid receptor antagonist that was developed for the treatment of opioid-induced constipation. Modeling and simulation of naloxegol efficacy and tolerability informed selection of doses for phase III studies and provided comprehensive dosage recommendations for the naloxegol US package insert.

Drug-disease modeling in the pharmaceutical industry - where mechanistic systems pharmacology and statistical pharmacometrics meet

Modeling & simulation (M&S) methodologies are established quantitative tools, which have proven to be useful in supporting the research, development (R&D), regulatory approval, and marketing of novel therapeutics. Applications of M&S help design efficient studies and interpret their results in context of all available data and knowledge to enable effective decision-making during the R&D process. In this mini-review, we focus on two sets of modeling approaches: population-based models, which are well-established within the pharmaceutical industry today, and fall under the discipline of clinical pharmacometrics (PMX); and systems dynamics models, which encompass a range of models of (patho-)physiology amenable to pharmacological intervention, of signaling pathways in biology, and of substance distribution in the body (today known as physiologically-based pharmacokinetic models) - which today may be collectively referred to as quantitative systems pharmacology models (QSP). We next describe the convergence - or rather selected integration - of PMX and QSP approaches into 'middle-out' drug-disease models, which retain selected mechanistic aspects, while remaining parsimonious, fit-for-purpose, and able to address variability and the testing of covariates. We further propose development opportunities for drug-disease systems models, to increase their utility and applicability throughout the preclinical and clinical spectrum of pharmaceutical R&D.

Pharmacologic Profile of Naloxegol, a Peripherally Acting µ-Opioid Receptor Antagonist, for the Treatment of Opioid-Induced Constipation

Opioid-induced constipation (OIC) is a common side effect of opioid pharmacotherapy for the management of pain because opioid agonists bind to µ-opioid receptors in the enteric nervous system (ENS). Naloxegol, a polyethylene glycol derivative of naloxol, which is a derivative of naloxone and a peripherally acting µ-opioid receptor antagonist, targets the physiologic mechanisms that cause OIC. Pharmacologic measures of opioid activity and pharmacokinetic measures of central nervous system (CNS) penetration were employed to characterize the mechanism of action of naloxegol. At the human µ-opioid receptor in vitro, naloxegol was a potent inhibitor of binding (Ki = 7.42 nM) and a neutral competitive antagonist (pA2 - 7.95); agonist effects were <10% up to 30 μM and identical to those of naloxone. The oral doses achieving 50% of the maximal effect in the rat for antagonism of morphine-induced inhibition of gastrointestinal transit and morphine-induced antinociception in the hot plate assay were 23.1 and 55.4 mg/kg for naloxegol and 0.69 and 1.14 mg/kg by for naloxone, respectively. In the human colon adenocarcinoma cell transport assay, naloxegol was a substrate for the P-glycoprotein transporter, with low apparent permeability in the apical to basolateral direction, and penetrated the CNS 15-fold slower than naloxone in a rat brain perfusion model. Naloxegol-derived radioactivity was poorly distributed throughout the rat CNS and was eliminated from most tissues within 24 hours. These findings corroborate phase 3 clinical studies demonstrating that naloxegol relieves OIC-associated symptoms in patients with chronic noncancer pain by antagonizing the µ-opioid receptor in the ENS while preserving CNS-mediated analgesia.

Determination of naloxegol in human biological matrices

Aim: Naloxegol is an oral peripherally acting μ-opioid receptor antagonist approved for the treatment of opioid-induced constipation. Sensitive, robust, bioanalytical methods were required to quantitate naloxegol in human biological matrices as part of the clinical development program. Methodology/results: Analytical plasma samples were prepared using Solid Phase Extraction (SPE) coupled with concentration. The method’s linearity was established at 0.1–50 ng/ml with up to 100-fold dilution. Urine samples were analyzed directly postdilution; dialysate samples were extracted by supported liquid extraction. Sensitive liquid chromatography/mass spectrometry (LC–MS/MS) assays were developed and validated, and demonstrated acceptable precision, accuracy and selectivity for naloxegol in the appropriate matrices. Conclusion: Methods for quantifying naloxegol in human biological matrices have been successfully validated.

An Open-Label, Randomized Bioavailability Study of Alternative Methods of Oral Administration of Naloxegol in Healthy Subjects

Naloxegol is a peripherally acting μ-opioid receptor antagonist approved as an orally administered tablet for the treatment of opioid-induced constipation. Patients with swallowing difficulties may benefit from alternative approaches to the oral administration of the whole-tablet formulation of naloxegol. This open-label, randomized, 4-period, 4-treatment, crossover, single-dose study (NCT02446171) evaluated the pharmacokinetic (PK) characteristics of crushed naloxegol 25-mg tablets (suspended in water) administered orally or by nasogastric tube and a naloxegol solution compared with the commercially available 25-mg tablet formulation in healthy volunteers. The PK profiles for the crushed tablet, whether administered orally or by nasogastric tube, and the 25-mg oral solution were similar to that of the 25-mg tablet administered orally. Compared with naloxegol commercial tablets, the relative bioavailability of naloxegol using 3 alternative methods of administration was approximately 100%. For each pairwise treatment comparison of the 3 alternative methods with the approved whole tablet, the geometric least-squares mean ratio ranges were 94.37%-100.04%, 94.83%-100.44%, and 97.05%-102.05% for area under the curve (AUC), AUC_0-t , and maximum plasma concentration, respectively, and their 90% confidence intervals were entirely within the predefined 80% to 125% bioequivalence limits. Naloxegol was well tolerated when administered in both liquid and solid form.

The role of naloxegol in the management of opioid-induced bowel dysfunction

Opioid-induced constipation (OIC) and other gastrointestinal (GI) symptoms of opioid-induced bowel dysfunction (OIBD) significantly deteriorate patients' quality of life and may lead to noncompliance with opioid schedule and undertreatment of pain. Although traditional oral laxatives are the first-line treatment of OIC, they do not address OIBD pathophysiology, and display numerous adverse effects. OIC treatment includes prokinetics (lubiprostone), opioid switch, and changing route of opioid administration. Targeted management of OIBD comprises the use of purely peripherally acting μ-opioid receptor antagonists (PAMORA): naloxegol and methylnaltrexone. Naloxegol (NKTR-118) is a polymer conjugate of the opioid antagonist naloxone. The polyethylene glycol limits naloxegol capacity to cross the blood-brain barrier (BBB). Naloxegol is substrate for the P-glycoprotein (P-gp) transporter. The central nervous system penetration of naloxegol is negligible due to reduced permeability and its increased efflux across the BBB, related to P-gp transporter. Naloxegol antagonizes μ- and κ-opioid receptors and displays low affinity to δ-opioid receptors in the GI tract, thereby decreasing OIBD symptoms without reversing central analgesic effects. Naloxegol is metabolised through CYP3A4 to six metabolites, with the majority of the dose (68%) excreted with faeces and less (16%) with urine. The dose of naloxegol equals 25 mg administered orally once daily on a fasting condition. Mild or moderate hepatic impairment has no impact on naloxegol dosing; naloxegol was not studied and is not recommended in patients with hepatic failure. Dose reduction (12.5 mg once daily) and caution is recommended in patients with moderate-to-severe renal impairment. Efficacy (bowel movement in 42-49% of patients not responsive to laxatives) and safety of naloxegol were confirmed in studies conducted in patients with OIC and nonmalignant pain. Naloxegol may be useful for cancer patients with OIC, although studies in this population are lacking.

Population Exposure-Response Modeling of Naloxegol in Patients With Noncancer-Related Pain and Opioid-Induced Constipation

Naloxegol is a polyethylene glycol derivative of naloxone approved in the US as a once-daily oral treatment for opioid-induced constipation (OIC) in adults with chronic noncancer pain. Population exposure-response models were constructed based on data from two phase III studies comprising 1,331 adults with noncancer pain and OIC. In order to characterize the protocol-defined naloxegol responder rate, the number of daily spontaneous bowel movements (SBMs) was characterized by a longitudinal ordinal nonlinear mixed-effects logistic regression dose-response model, and the incidence of diary entry discontinuation was described by a time-to-event model. The mean number of SBMs per week increased with increasing naloxegol dose. The predicted placebo-adjusted responder rates (90% confidence interval) were 10.4% (4.6-13.4%) and 11.1% (4.8-14.4%) for naloxegol 12.5 and 25 mg/day, respectively. Model-predicted response to naloxegol was influenced by the baseline SBM frequency and characteristics of the opioid treatment.

Population pharmacokinetics of naloxegol in a population of 1247 healthy subjects and patients

AIMS

Naloxegol, a polyethylene glycol conjugated derivative of the opioid antagonist naloxone, is in clinical development for treatment of opioid-induced constipation (OIC). The aim of the study was to develop a population pharmacokinetic model describing the concentration vs. time profile of orally administered naloxegol, and determine the impact of pre-specified demographic and clinical factors and concomitant medication on population estimates of apparent clearance (CL/F) and apparent central compartment volume of distribution (Vc /F).

METHODS

Analysis included 12,844 naloxegol plasma concentrations obtained from 1247 healthy subjects, patients with non-OIC and patients with OIC in 14 phase 1, 2b and 3 clinical studies. Pharmacokinetic analysis used the non-linear mixed effects modelling program. Goodness of fit plots and posterior predictive checks were conducted to confirm concordance with observed data.

RESULTS

The final model was a two compartment disposition model with dual absorptions, comprising one first order absorption (ka1 4.56 h(-1) ) and one more complex absorption with a transit compartment (ktr 2.78 h(-1) ). Mean (SE) parameter estimates for CL/F and Vc /F, the parameters assessed for covariate effects, were 115 (3.41) l h(-1) and 160 (27.4) l, respectively. Inter-individual variability was 48% and 51%, respectively. Phase of study, gender, race, concomitant strong or moderate CYP3A4 inhibitors, strong CYP3A4 inducers, P-glycoprotein inhibitors or inducers, naloxegol formulation, baseline creatinine clearance and baseline opioid dose had a significant effect on at least one pharmacokinetic parameter. Simulations indicated concomitant strong CYP3A4 inhibitors or inducers had relevant effects on naloxegol exposure.

CONCLUSIONS

Administration of strong CYP3A4 inhibitors or inducers had a clinically relevant influence on naloxegol pharmacokinetics.