Population modeling analyses of crizotinib in pediatric patients with ALK-positive advanced cancers.

BACKGROUND: Alterations in the ALK (anaplastic lymphoma kinase) gene play a critical role in pathogenesis of anaplastic large cell lymphoma (ALCL). Crizotinib is a small molecule competitive inhibitor of ALK, ROS1, and MET kinases and was approved for pediatric patients with ALK-positive relapsed or refractory, systemic ALCL, and ALK-positive unresectable, recurrent, or refractory inflammatory myofibroblastic tumors (IMT). PROCEDURE: Crizotinib data from pediatric patients with relapsed or refractory solid tumors, IMT, or ALCL were included in the analyses. All patients received crizotinib orally at doses ranging from 100 to 365 mg/m2 twice daily (BID). PopPK analyses were conducted to characterize crizotinib disposition in pediatric patients. Exposure-response (ER) safety and antitumor analyses were conducted to characterize relationships between crizotinib dose or exposure with safety and antitumor activity endpoints of interest. RESULTS: The population pharmacokinetic (popPK), ER safety, and ER antitumor analysis included 98, 110, and 36 pediatric patients, respectively. A one-compartment pharmacokinetic model with allometric scaling, first-order elimination, and first-order absorption with lag time adequately described the data. Natural log-transformed model-predicted crizotinib AUCss (steady-state area under the concentration-time curve) demonstrated a significant, positive relationship with Grade ≥3 NEUTROPENIA and Any Grade VISION DISORDER. Crizotinib dose demonstrated a positive relationship with objective response rate. CONCLUSIONS: No significant differences in PK were identified across a wide range of ages or across tumor types, suggesting body surface area (BSA)-based dosing adequately adjusted for differences in patient size to achieve similar systemic crizotinib exposures across young children and adolescent pediatric patients. None of the myelosuppressive events except Grade ≥3 NEUTROPENIA had significant relationships identified with crizotinib dose or exposure, suggesting crizotinib is a tolerable treatment with less hematological toxicity than traditional chemotherapy regimens for pediatric patients with ALK-mutated cancers. Results from the presented analyses support the pediatric dosing recommendations in the product label.

The impact of CYP3A4 genetic polymorphism on crizotinib metabolism and drug-drug interactions.

To elucidate the impact of CYP3A4 activity inhibition and genetic polymorphism on the metabolism of crizotinib. Enzymatic incubation systems for crizotinib were established, and Sprague-Dawley rats were utilized for in vivo experiments. Analytes were quantified using LC-MS/MS. Upon screening 122 drugs and natural compounds, proanthocyanidins emerged as inhibitor of crizotinib metabolism, exhibiting a relative inhibition rate of 93.7%. The IC50 values were 24.53 ± 0.32 µM in rat liver microsomes and 18.24 ± 0.12 µM in human liver microsomes. In vivo studies revealed that proanthocyanidins markedly affected the pharmacokinetic parameters of crizotinib. Co-administration led to a significant reduction in the AUC(0-t), Cmax of PF-06260182 (the primary metabolite of crizotinib), and the urinary metabolic ratio. This interaction is attributed to the mixed-type inhibition of liver microsome activity by proanthocyanidins. CYP3A4, being the principal metabolic enzyme for crizotinib, has its genetic polymorphisms significantly influencing crizotinib's pharmacokinetics. Kinetic data showed that the relative metabolic rates of crizotinib across 26 CYP3A4 variants ranged from 13.14% (CYP3A4.12, 13) to 188.57% (CYP3A4.33) when compared to the wild-type CYP3A4.1. Additionally, the inhibitory effects of proanthocyanidins varied between CYP3A4.12 and CYP3A4.33, when compared to the wild type. Our findings indicate that proanthocyanidins coadministration and CYP3A4 genetic polymorphism can significantly influence crizotinib metabolism.

Simultaneous determination of unecritinib (TQ-B3101) and its active metabolite crizotinib in rat plasma by LC-MS/MS：An application to pharmacokinetic studies.

Unecritinib (TQ-B3101) is a selective tyrosine kinase receptor inhibitor. In the study, in vitro metabolic experiments revealed that the hydrolysis of TQ-B3101 was mainly catalyzed by carboxylesterase 2 (CES2), followed by CES1. Next, a sensitive and reliable LC-MS/MS method was established for the simultaneous determination of TQ-B3101 and its metabolite crizotinib in rat plasma. To prevent in vitro hydrolysis of TQ-B3101, sodium fluoride, the CESs inhibitor at a concentration of 2 M, was immediately added after whole blood collection. Plasma samples were extracted by acetonitrile-induced protein precipitation method, and chromatographically separated on a Gemini C18 column (50 mm × 2.0 mm i.d., 5 µm) using gradient elution with a mobile phase of 0.1% formic acid and 5 mmol/L ammonium acetate with 0.1% formic acid. The retention times for TQ-B3101 and crizotinib were 2.61 and 2.38 min, respectively. The analytes were detected with tandem mass spectrometer by positive electrospray ionization, using the ion transitions at m/z 492.3 → 302.3 for TQ-B3101, m/z 450.3 → 260.3 for crizotinib, and m/z 494.0 → 394.3 for imatinib (internal standard). Method validation was conducted in the linear range of 1.00-800 ng/mL for the two analytes. The precision, accuracy and stabilities all met the acceptance criteria. The pharmacokinetic study indicated that TQ-B3101 was rapidly hydrolyzed to crizotinib with the elimination half-life of 1.11 h after a single gavage administration of 27 mg/kg to Sprague-Dawley rats, and the plasma exposure of TQ-B3101 was only 2.98% of that of crizotinib.

Population pharmacokinetic analysis of crizotinib in children with progressive/recurrent high-grade and diffuse intrinsic pontine gliomas.

PURPOSE: Crizotinib, a potent oral tyrosine kinase inhibitor, was evaluated in combination with dasatinib in a phase 1 trial (NCT01644773) in children with progressive or recurrent high-grade and diffuse intrinsic pontine gliomas (HGG and DIPG). This study aimed to characterize the pharmacokinetics of crizotinib in this population and identify significant covariates. METHODS: Patients (N = 36, age range 2.9-21.3 years) were treated orally once or twice-daily with 100-215 mg/m2 crizotinib and 50-65 mg/m2 dasatinib. Pharmacokinetic studies were performed for crizotinib alone after the first dose and at steady state, and for the drug combination at steady state. Crizotinib plasma concentrations were measured using a validated LC-MS/MS method. Population modeling was performed (Monolix) and the impact of factors including patient demographics and co-medications were investigated on crizotinib pharmacokinetics. RESULTS: Crizotinib concentrations were described with a linear two-compartment model and absorption lag time. Concomitant dasatinib and overweight/obese status significantly influenced crizotinib pharmacokinetics, resulting in clinically relevant impact (> 20%) on drug exposure. Crizotinib mean apparent clearance (CL/F) was 66.7 L/h/m2 after single-dose and decreased to 26.5 L/h/m2 at steady state when given alone, but not when combined with dasatinib (mean 60.8 L/h/m2). Overweight/obese patients exhibited lower crizotinib CL/F and apparent volume V1/F (mean 46.2 L/h/m2 and 73.3 L/m2) compared to other patients (mean 75.5 L/h/m2 and 119.3 L/m2, p < 0.001). CONCLUSION: A potential pharmacokinetic interaction was observed between crizotinib and dasatinib in children with HGG and DIPG. Further, crizotinib exposure was significantly higher in overweight/obese patients, who may require a dosing adjustment.

Pharmacoenhancement of Low Crizotinib Plasma Concentrations in Patients with Anaplastic Lymphoma Kinase-Positive Non-Small Cell Lung Cancer using the CYP3A Inhibitor Cobicistat.

The inhibitor of anaplastic lymphoma kinase (ALK) crizotinib significantly increases survival in patients with ALK-positive non-small cell lung cancer (NSCLC). When evaluating crizotinib pharmacokinetics (PKs) in patients taking the standard flat oral dose of 250 mg b.i.d., interindividual PK variability is substantial and patient survival is lower in the quartile with the lowest steady-state trough plasma concentrations (Cmin,ss ), suggesting that concentrations should be monitored and doses individualized. We investigated whether the CYP3A inhibitor cobicistat increases Cmin,ss of the CYP3A substrate crizotinib in patients with low exposure. Patients with ALK-positive NSCLC of our outpatient clinic treated with crizotinib were enrolled in a phase I trial (EudraCT 2016-002187-14, DRKS00012360) if crizotinib Cmin,ss was below 310 ng/mL and treated with cobicistat for 14 days. Crizotinib plasma concentration profiles were established before and after a 14-day co-administration of cobicistat to construct the area under the plasma concentration-time curve in the dosing interval from zero to 12 hours (AUC0-12 ). Patients were also monitored for adverse events by physical examination, laboratory tests, and 12-lead echocardiogram. Enrolment was prematurely stopped because of the approval of alectinib, a next-generation ALK-inhibitor with superior efficacy. In the only patient enrolled, cobicistat increased Cmin,ss from 158 ng/mL (before cobicistat) to 308 ng/mL (day 8) and 417 ng/mL (day 14 on cobicistat), concurrently the AUC0-12 increased by 78% from 2,210 ng/mL*h to 3,925 ng/mL*h. Neither safety signals nor serious adverse events occurred. Pharmacoenhancement with cobicistat as an alternative for dose individualisation for patients with NSCLC with low crizotinib exposure appears to be safe and is cost-effective and feasible.

Safety, tolerability and pharmacokinetics of crizotinib in combination with cytotoxic chemotherapy for pediatric patients with refractory solid tumors or anaplastic large cell lymphoma (ALCL): a Children's Oncology Group phase 1 consortium study (ADVL1212).

PURPOSE: This phase 1 study aimed to determine the safety, tolerability and recommended phase 2 dose (RP2D) of crizotinib in combination with cytotoxic chemotherapy for children with refractory solid tumors and ALCL. METHODS: Pediatric patients with treatment refractory solid tumors or ALCL were eligible. Using a 3 + 3 design, crizotinib was escalated in three dose levels: 165, 215, or 280 mg/m2/dose BID. In Part A, patients received crizotinib oral solution (OS) in combination with topotecan and cyclophosphamide (topo/cyclo); in Part B, crizotinib OS was administered with vincristine and doxorubicin (vcr/dox). In Parts C and D, patients received topo/cyclo in combination with either crizotinib-formulated capsules (FC) or microspheres (cMS), respectively. Crizotinib pharmacokinetic evaluation was required. RESULTS: Forty-four eligible patients were enrolled, 39 were evaluable for toxicity. Parts A and B were terminated due to concerns regarding palatability and tolerability of the OS. In Part C, crizotinib, FC 215 mg/m2/dose BID, in combination with topo/cyclo was tolerated. In Part D, the maximum tolerated dose (MTD) was exceeded at 165 mg/m2/dose of crizotinib cMS. Pharmacokinetics of crizotinib in combination with chemotherapy was similar to single-agent crizotinib and exposures were not formulation dependent. CONCLUSIONS: The RP2D of crizotinib FCs in combination with cyclophosphamide and topotecan was 215 mg/m2/dose BID. The oral solution of crizotinib was not palatable in this patient population. Crizotinib cMS was palatable; however, patients experienced increased toxicity that was not explained by the relative bioavailability or exposure and warrants further investigation. CLINICAL TRIAL REGISTRY: The trial is registered as NCT01606878 at Clinicaltrials.gov.

Combination treatments with hydroxychloroquine and azithromycin are compatible with the therapeutic induction of anticancer immune responses.

Amid controversial reports that COVID-19 can be treated with a combination of the antimalarial drug hydroxychloroquine (HCQ) and the antibiotic azithromycin (AZI), a clinical trial (ONCOCOVID, NCT04341207) was launched at Gustave Roussy Cancer Campus to investigate the utility of this combination therapy in cancer patients. In this preclinical study, we investigated whether the combination of HCQ+AZI would be compatible with the therapeutic induction of anticancer immune responses. For this, we used doses of HCQ and AZI that affect whole-body physiology (as indicated by a partial blockade in cardiac and hepatic autophagic flux for HCQ and a reduction in body weight for AZI), showing that their combined administration did not interfere with tumor growth control induced by the immunogenic cell death inducer oxaliplatin. Moreover, the HCQ+AZI combination did not affect the capacity of a curative regimen (cisplatin + crizotinib + PD-1 blockade) to eradicate established orthotopic lung cancers in mice. In conclusion, it appears that HCQ+AZI does not interfere with the therapeutic induction of therapeutic anticancer immune responses.

Brigatinib Versus Crizotinib in Advanced ALK Inhibitor-Naive ALK-Positive Non-Small Cell Lung Cancer: Second Interim Analysis of the Phase III ALTA-1L Trial.

PURPOSE: Brigatinib, a next-generation anaplastic lymphoma kinase (ALK) inhibitor, demonstrated superior progression-free survival (PFS) and improved health-related quality of life (QoL) versus crizotinib in advanced ALK inhibitor-naive ALK-positive non-small cell lung cancer (NSCLC) at first interim analysis (99 events; median brigatinib follow-up, 11.0 months) in the open-label, phase III ALTA-1L trial (ClinicalTrials.gov identifier: NCT02737501). We report results of the second prespecified interim analysis (150 events). METHODS: Patients with ALK inhibitor-naive advanced ALK-positive NSCLC were randomly assigned 1:1 to brigatinib 180 mg once daily (7-day lead-in at 90 mg once daily) or crizotinib 250 mg twice daily. The primary end point was PFS as assessed by blinded independent review committee (BIRC). Investigator-assessed efficacy, blood samples for pharmacokinetic assessments, and patient-reported outcomes were also collected. RESULTS: Two hundred seventy-five patients were randomly assigned (brigatinib, n = 137; crizotinib, n = 138). With median follow-up of 24.9 months for brigatinib (150 PFS events), brigatinib showed consistent superiority in BIRC-assessed PFS versus crizotinib (hazard ratio [HR], 0.49 [95% CI, 0.35 to 0.68]; log-rank P < .0001; median, 24.0 v 11.0 months). Investigator-assessed PFS HR was 0.43 (95% CI, 0.31 to 0.61; median, 29.4 v 9.2 months). No new safety concerns emerged. Brigatinib delayed median time to worsening of global health status/QoL scores compared with crizotinib (HR, 0.70 [95% CI, 0.49 to 1.00]; log-rank P = .049). Brigatinib daily area under the plasma concentration-time curve was not a predictor of PFS (HR, 1.005 [95% CI, 0.98 to 1.031]; P = .69). CONCLUSION: Brigatinib represents a once-daily ALK inhibitor with superior efficacy, tolerability, and QoL over crizotinib, making it a promising first-line treatment of ALK-positive NSCLC.

Synthesis and evaluation of 18F labeled crizotinib derivative [18F]FPC as a novel PET probe for imaging c-MET-positive NSCLC tumor.

c-MET-positive NSCLC is an important subtype accounting for about 5%~22% of lung cancer. NSCLC patients with activating c-MET are intensively sensitive to c-MET selective receptor tyrosine kinase (RTK) inhibitors, so we aimed to develop a specific PET probe targeting to c-MET-positive NSCLC for potential patients screened by PET/CT. Herein, PET tracer 18F-radiolabeled crizotinib derivative ([18F]FPC) was successfully achieved through a simple one-step 18F-labeling method. [18F]FPC PET imaging on c-MET-positive (as well as blocking group) and negative NSCLC models were further evaluated, and results showed that [18F]FPC was effective as a PET imaging probe that targeted c-MET-positive tumor. Therefore, [18F]FPC could be a potential PET imaging probe for NSCLC tumor which was sensitive to c-MET-TKIs. By virtue of this property, it will benefit NSCLC patients for c-MET-TKI treatment.

Dose-escalation trial of the ALK, MET & ROS1 inhibitor, crizotinib, in patients with advanced cancer.

Aim: This first-in-human, dose-finding study evaluated safety, pharmacokinetics and pharmacodynamics of crizotinib and established a recommended Phase II dose (RP2D) among patients with advanced solid malignancies. Patients & methods: Patients received oral crizotinib in a 3 + 3 dose escalation design. Results: Thirty-six patients received crizotinib (50 mg once daily-300 mg twice daily); maximum tolerated dose (and RP2D) was 250 mg twice daily. Most patients (89%) experienced ≥1 treatment-related adverse event. Three patients had grade 3 dose-limiting toxicities: alanine aminotransferase increased (n = 1) and fatigue (n = 2). Generally, an increase in soluble MET was found with increasing crizotinib concentrations. Conclusion: Crizotinib demonstrated a favorable safety profile. The observed pharmacodynamic effect on soluble MET provide evidence for targeted MET inhibition by crizotinib. Clinicaltrials. gov identifier: NCT00585195.

Pharmacokinetic herb-drug interaction between ginger and crizotinib.

The use of complementary and alternative medicine at least once during or after cancer treatment has increased over the past years from an estimated 25% in the 1970s and 1980s to more than 32% in the 1990s and to 49% after 2000. The risk of herb-drug interaction is therefore increasingly recognized as a public health problem. To the best of our knowledge, we report here the first case of interaction between ginger and anticancer drug, with serious consequences for the patient. There is an urgent need regarding complementary and alternative medicine: Both clinicians and patients should be aware of the potential interactions between herbs and prescribed drugs.

Management of CNS disease in ALK-positive non-small cell lung cancer: Is whole brain radiotherapy still needed?

Anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (3 to 5% of all non-small cell lung cancers) carries a particularly high risk of central nervous system dissemination (60% to 90%). As the use of ALK inhibitors improves treatment outcomes over chemotherapy, the determent of central nervous system metastases has become an increasingly relevant therapeutic dilemma considering young age and possible extended overall survival. The goal of brain metastases management is to optimize both overall survival and quality of life, with the high priority of neurocognitive function preservation. Unfortunately in the first year on crizotinib, the pioneering ALK inhibitors, approximately one third of these patients fail in the central nervous system, which is explained by an inadequate central nervous system drug penetration through the blood-brain barrier. Central nervous system-directed radiotherapy represents the most important strategy to control intracranial disease burden and extend the survival benefit with crizotinib. The role of whole brain irradiation in the treatment of brain metastases diminishes, as this technique is associated with the risk of neurocognitive decline. Stereotactic radiotherapy represents an alternative technique that delivers ablative doses of ionizing radiation to the limited volume of oligometastatic brain disease, offering sparing of the adjacent brain parenchyma and reduced neurotoxicity. The next generation ALK inhibitors were designed to cross the blood-brain barrier more efficiently than crizotinib and achieve higher concentration in the cerebrospinal fluid, offering prominent ability to control central nervous system spread. In the phase III ALEX trial the intracranial control was significantly better with alectinib as compared to crizotinib and it translated into survival benefit. Other next generation ALK inhibitors (i.e. ceritinib, brigatinib, lorlatinib) also demonstrated promising activity in the central nervous system.

Clinical implications of an analysis of pharmacokinetics of crizotinib coadministered with dexamethasone in patients with non-small cell lung cancer.

PURPOSE: Dexamethasone is a systemic corticosteroid and a known cytochrome P450 (CYP)3A inducer. Crizotinib is a selective tyrosine kinase inhibitor of ALK, ROS1, and MET and a substrate of CYP3A. This post hoc analysis characterized the use of concomitant CYP3A inducers with crizotinib and estimated the effect of dexamethasone use on crizotinib pharmacokinetics at steady state. METHODS: This analysis used data from four clinical studies (PROFILE 1001, 1005, 1007, and 1014) including 1690 patients with non-small cell lung cancer with ALK or ROS1 rearrangements treated with crizotinib at 250 mg twice daily. Frequency and reasons for use of concomitant CYP3A inducers, including dexamethasone, with crizotinib were characterized. Multiple steady-state trough concentrations (Ctrough,ss) of crizotinib were measured for each patient. A linear mixed-effects model was used for within-patient comparison of crizotinib Ctrough,ss between dosing of crizotinib alone and crizotinib coadministered with dexamethasone consecutively for ≥ 21 days. RESULTS: Dexamethasone was the most commonly used CYP3A inducer (30.4%). A total of 15 patients had crizotinib Ctrough,ss for both crizotinib dosing with and without dexamethasone. The adjusted geometric mean ratio of crizotinib Ctrough,ss following coadministration with dexamethasone relative to crizotinib without dexamethasone, as a percentage, was 98.2% (90% confidence interval, 79.1-122.0%). CONCLUSIONS: Crizotinib plasma exposure following coadministration with dexamethasone was similar to that when crizotinib was administered without dexamethasone, indicating dexamethasone has no effect on crizotinib exposure or efficacy. Other CYP3A inducers with similar potency would likewise have no clinically relevant effect on crizotinib exposure.

Synthesis of hapten, generation of specific polyclonal antibody and development of ELISA with high sensitivity for therapeutic monitoring of crizotinib.

Crizotinib (CZT) is a potent drug used for treatment of non-small cell lung cancer (NSCLC); however, its circulating concentration variability has been associated with acquired resistance and toxicity, restricting the success of cancer treatment. As such, the development of an assay that monitors CZT plasma concentrations in patients is a valuable tool in cancer treatment. In this study, a hapten of CZT was synthesized by introducing the acetohydrazide moiety as a spacer into the chemical structure of CZT. The chemical structure of the CZT acetohydrazide (hapten) was confirmed by mass, 1H-, and 13C-NMR spectrometric techniques. The hapten was coupled to each of bovine serum albumin (BSA) and keyhole limpet hemocyanin (KLH) proteins by ethyl-3-(3-dimethylaminopropyl) carbodiimide as a coupling reagent. CZT-KLH conjugate was used for immunization and generation of a polyclonal antibody recognizing CZT with high affinity (IC50 = 0.5 ng/mL). The polyclonal antibody was used in the development of an ELISA for determination of CZT. The ELISA involved a competitive binding reaction between CZT, in its samples, and immobilized CZT-BSA conjugate for the binding sites on a limited amount of the anti-CZT antibody. The assay limit of detection was 0.03 ng/mL and the working range was 0.05 - 24 ng/mL. Analytical recovery of CZT from spiked plasma was 101.98 ± 2.99%. The precisions of the assay were satisfactory; RSD was 3.2 - 6.5% and 4.8 - 8.2%, for the intra- and inter-assay precision, respectively. The assay is superior to all the existing chromatographic methods for CZT in terms of its procedure simplicity, convenience, and does not require treatment of plasma samples prior to the analysis. The proposed ELISA is anticipated to effectively contribute to the therapeutic monitoring of CZT in clinical settings.

Clinical Pharmacokinetics of Anaplastic Lymphoma Kinase Inhibitors in Non-Small-Cell Lung Cancer.

The identification of anaplastic lymphoma kinase rearrangements in 2-5% of patients with non-small-cell lung cancer led to rapid advances in the clinical development of oral tyrosine kinase inhibitors. Anaplastic lymphoma kinase inhibitors are an effective treatment in preclinical models and patients with anaplastic lymphoma kinase-translocated cancers. Four anaplastic lymphoma kinase inhibitors (crizotinib, ceritinib, alectinib, and brigatinib) have recently been approved. Post-marketing studies provided additional pharmacokinetic information on their pharmacokinetic parameters. The pharmacokinetic properties of approved anaplastic lymphoma kinase inhibitors have been reviewed herein. Findings from additional studies on the effects of drug-metabolizing enzymes, drug transporters, and drug-drug interactions have been incorporated. Crizotinib, ceritinib, and alectinib reach their maximum plasma concentrations after approximately 6 h and brigatinib after 1-4 h. These drugs are primarily metabolized by cytochrome P450 3A with other cytochrome P450 enzymes. They are mainly excreted in the feces, with only a minor fraction being eliminated in urine. Crizotinib, ceritinib, and brigatinib are substrates for the adenosine triphosphate binding-cassette transporter B1, whereas alectinib is not. The different substrate specificities of the transporters play a key role in superior blood-brain barrier penetration by alectinib than by crizotinib and ceritinib. Although the absorption, distribution, and excretion of anaplastic lymphoma kinase inhibitors are regulated by drug transporters, their transporter-mediated pharmacokinetics have not yet been elucidated in detail in patients with non-small-cell lung cancer. Further research to analyze the contribution of drug transporters to the pharmacokinetics of anaplastic lymphoma kinase inhibitors in patients with non-small-cell lung cancer will be helpful for understanding the mechanisms of the inter-individual differences in the pharmacokinetics of anaplastic lymphoma kinase inhibitors.

Evaluation of hepatic impairment on pharmacokinetics and safety of crizotinib in patients with advanced cancer.

PURPOSE: This phase 1 study evaluated the effect of hepatic impairment on pharmacokinetics and safety of crizotinib in patients with advanced cancer. METHODS: Patients were dosed according to hepatic function classified by modified National Cancer Institute Organ Dysfunction Working Group criteria and group assignment [normal (A1 and A2), mild (B), moderate (C1 and C2), or severe (D)]. Primary pharmacokinetic endpoints included area under the concentration-time curve as daily exposure (AUCdaily) and maximum plasma concentration (Cmax) at steady state. Safety endpoints included types, incidence, seriousness, and relationship to crizotinib of adverse events. RESULTS: The AUCdaily and Cmax in patients with normal liver function were 7107 ng h/mL and 375.1 ng/mL (A1) and 5422 ng h/mL and 283.9 ng/mL (A2), respectively. The AUCdaily and Cmax ratios of adjusted geometric means for Groups B, C2, and D versus Group A1 were 91.12 and 91.20, 114.08 and 108.87, and 64.47 and 72.63, respectively. Any grade treatment-related adverse events (TRAEs) occurred in 75% of patients; grade 3/4 TRAEs occurred in 25%, including fatigue (6%), hyponatremia (5%), and hyperbilirubinemia (3%). CONCLUSIONS: No adjustment to the approved 250 mg twice daily (BID) dose of crizotinib is recommended for patients with mild hepatic impairment. The recommended dose is 200 mg BID for patients with moderate hepatic impairment, and the dose should not exceed 250 mg daily for patients with severe hepatic impairment. Adverse events appeared consistent among the hepatic impairment groups. CLINICAL TRIAL REGISTRATION NO: NCT01576406.