Safety and Pharmacokinetics of Quizartinib Combination Therapy With Standard Induction and Consolidation Chemotherapy in Patients With Newly Diagnosed Acute Myeloid Leukemia: Results from Two Phase 1 Trials in Japan and China.

Quizartinib is a potent, oral, second-generation, selective type II FMS-like receptor tyrosine kinase 3 (FLT3) inhibitor. It has shown improved overall survival in a randomized, multinational, Phase 3 (QuANTUM-First) study in patients with FLT3-internal tandem duplication (ITD)-positive newly diagnosed acute myeloid leukemia. We conducted 2 Phase 1b studies in Japan and China to evaluate the safety, pharmacokinetics, and efficacy of quizartinib in combination with standard induction and consolidation chemotherapy in patients with newly diagnosed acute myeloid leukemia. Quizartinib was started at a dose level of 20 mg/day and then escalated to 40 mg/day, the dose used in the Phase 3 study. Seven patients were enrolled according to the 3 + 3 dose-escalation method in each study, including 3 patients who were FLT3-ITD positive. No dose-limiting toxicities were observed at dose levels up to 40 mg/day in both studies. Grade 3 or higher, quizartinib-related, treatment-emergent adverse events included febrile neutropenia, hematologic toxicities, and infections. QT prolongation on electrocardiogram was observed in 5 patients. The pharmacokinetics of quizartinib and its metabolite AC886 were similar between the studies and consistent with previous findings in the United States. We confirmed the tolerability of Japanese and Chinese patients to the dose of quizartinib and chemotherapy regimens used in the QuANTUM-First study.

Pharmacokinetic Interactions between Canagliflozin and Sorafenib or Lenvatinib in Rats.

Hepatocellular carcinoma (HCC) and type 2 diabetes mellitus (T2DM) are common clinical conditions, and T2DM is an independent risk factor for HCC. Sorafenib and lenvatinib, two multi-targeted tyrosine kinase inhibitors, are first-line therapies for advanced HCC, while canagliflozin, a sodium-glucose co-transporter 2 inhibitor, is widely used in the treatment of T2DM. Here, we developed an ultra-performance liquid chromatography-tandem mass spectrometry method for the simultaneous determination of canagliflozin, sorafenib, and lenvatinib, and investigated the pharmacokinetic drug interactions between canagliflozin and sorafenib or lenvatinib in rats. The animals were randomly divided into five groups. Groups I-III were gavage administrated with sorafenib, lenvatinib, and canagliflozin, respectively. Group IV received sorafenib and canagliflozin; while Group V received lenvatinib and canagliflozin. The area under the plasma concentration-time curves (AUC) and maximum plasma concentrations (Cmax) of canagliflozin increased by 37.6% and 32.8%, respectively, while the apparent volume of distribution (Vz/F) and apparent clearance (CLz/F) of canagliflozin significantly decreased (30.6% and 28.6%, respectively) in the presence of sorafenib. Canagliflozin caused a significant increase in AUC and Cmax of lenvatinib by 28.9% and 36.2%, respectively, and a significant decrease in Vz/F and CLz/F of lenvatinib by 52.9% and 22.7%, respectively. In conclusion, drug interactions exist between canagliflozin and sorafenib or lenvatinib, and these findings provide a reference for the use of these drugs in patients with HCC and T2DM.

A Simple UPLC/MS-MS Method for Simultaneous Determination of Lenvatinib and Telmisartan in Rat Plasma, and Its Application to Pharmacokinetic Drug-Drug Interaction Study.

Lenvatinib is a multi-targeted tyrosine kinase inhibitor that inhibits tumor angiogenesis, but hypertension is the most common adverse reaction. Telmisartan is an angiotensin receptor blocker used to treat hypertension. In this study, a simple ultra-performance liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of lenvatinib and telmisartan, and it was applied to the pharmacokinetic drug interaction study. Plasma samples were treated with acetonitrile to precipitate protein. Water (containing 5 mM of ammonium acetate and 0.1% formic acid) and acetonitrile (0.1% formic acid) were used as the mobile phases to separate the analytes with gradient elution using a column XSelect HSS T3 (2.1 mm × 100 mm, 2.5 µm). Multiple reaction monitoring in the positive ion mode was used for quantification. The method was validated and the precision, accuracy, matrix effect, recovery, and stability of this method were reasonable. The determination of analytes was not interfered with by other substances in the blank plasma, and the calibration curves of lenvatinib and telmisartan were linear within the range of 0.2-1000 ng/mL and 0.1-500 ng/mL, respectively. The results indicate that lenvatinib decreased the systemic exposure of telmisartan. Potential drug interactions were observed between lenvatinib and telmisartan.

Discovery, X-ray Crystallography, and Anti-inflammatory Activity of Bromodomain-containing Protein 4 (BRD4) BD1 Inhibitors Targeting a Distinct New Binding Site.

Bromodomain-containing protein 4 (BRD4) is an emerging epigenetic drug target for intractable inflammatory disorders. The lack of highly selective inhibitors among BRD4 family members has stalled the collective understanding of this critical system and the progress toward clinical development of effective therapeutics. Here we report the discovery of a potent BRD4 bromodomain 1 (BD1)-selective inhibitor ZL0590 (52) targeting a unique, previously unreported binding site, while exhibiting significant anti-inflammatory activities in vitro and in vivo. The X-ray crystal structural analysis of ZL0590 in complex with human BRD4 BD1 and the associated mutagenesis study illustrate a first-in-class nonacetylated lysine (KAc) binding site located at the helix αB and αC interface that contains important BRD4 residues (e.g., Glu151) not commonly shared among other family members and is spatially distinct from the classic KAc recognition pocket. This new finding facilitates further elucidation of the complex biology underpinning bromodomain specificity among BRD4 and its protein-protein interaction partners.

Impact of genetic polymorphisms on the pharmacokinetics and pharmacodynamics of lenvatinib in patients with hepatocellular carcinoma.

This prospective study examined the impact of genetic polymorphisms on the pharmacokinetics and clinical efficacy and safety of lenvatinib, a substrate of ATP-binding transporters, in a cohort of 48 Japanese patients with hepatocellular carcinoma (HCC). Pharmacokinetic studies were performed at the start of lenvatinib therapy (day 1) and on day 15. The coefficients of variation in AUC0-24h of lenvatinib on days 1 and 15 were 44.0% and 52.4%, respectively. Although the ABCB1 3435C > A, 1236C > T, and 2677G>T/A polymorphisms did not influence pharmacokinetic parameters, the AUC0-24h values on days 1 and 15 of the ABCG2 C/A or A/A group were approximately 1.1-fold and 1.4-fold that in the ABCG2 C/C group (P = 0.164 and 0.024). There were no significant differences in AUC0-24h on days 1 and 15 between the responders (complete or partial response) and non-responders (stable or progressive disease). The AUC0-24h on day 15 in those developing anorexia of any grade was significantly higher than that without such development (P = 0.017). In multivariate analysis, ABCG2 421C > A C/A or A/A was significantly associated with the development of anorexia (odds ratio 9.009, P = 0.009). ABCG2 421C > A polymorphism could affect exposure to lenvatinib and the development of anorexia.

Impact of co-administered stabilizers on the biopharmaceutical performance of regorafenib amorphous solid dispersions.

Poor solubility of drug candidates is a well-known and thoroughly studied challenge in the development of oral dosage forms. One important approach to tackle this challenge is the formulation as an amorphous solid dispersion (ASD). To reach the desired biopharmaceutical improvement a high supersaturation has to be reached quickly and then be conserved long enough for absorption to take place. In the presented study, various formulations of regorafenib have been produced and characterized in biorelevant in-vitro experiments. Povidone-based formulations, which are equivalent to the marketed product Stivarga®, showed a fast drug release but limited stability and robustness after that. In contrast, HPMCAS-based formulations exhibited excellent stability of the supersaturated solution, but unacceptably slow drug release. The attempt to combine the desired attributes of both formulations by producing a ternary ASD failed. Only co-administration of HPMCAS as an external stabilizer to the rapidly releasing Povidone-based ASDs led to the desired dissolution profile and high robustness. This optimized formulation was tested in a pharmacokinetic animal model using Wistar rats. Despite the promising in-vitro results, the new formulation did not perform better in the animal model. No differences in AUC could be detected when compared to the conventional (marketed) formulation. These data represent to first in-vivo study of the new concept of external stabilization of ASDs. Subsequent in-vitro studies revealed that temporary exposure of the ASD to gastric medium had a significant and long-lasting effect on the dissolution performance and externally administered stabilizer could not prevent this sufficiently. By applying the co-administered HPMCAS as an enteric coating onto Stivarga tablets, a new bi-functional approach was realized. This approach achieved the desired tailoring of the dissolution profile and high robustness against gastric medium as well as against seeding.

A Broad Range High-Throughput Assay for Lenvatinib Using Ultra-High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry With Clinical Application in Patients With Hepatocellular Carcinoma.

BACKGROUND: Lenvatinib is increasingly being selected as the first-line treatment for unresectable hepatocellular carcinoma (HCC) based on the results of the REFLECT trial. However, early discontinuation of lenvatinib because of adverse effects is a frequent occurrence. Hence, lenvatinib is a difficult drug for use in the clinical setting. One of the causes is that the dose of lenvatinib is mainly determined by body weight alone, despite high interindividual variability. To overcome this problem, a dosing regimen of lenvatinib based on a population pharmacokinetic (PPK) model for HCC patients is proposed. The aim of this study was to develop a high-throughput quantification method for lenvatinib using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) that can be applied to a PPK analysis of HCC patients in the future. METHODS: After a simple solid-phase extraction step using a 96-well plate, lenvatinib was analyzed by UHPLC-MS/MS in a positive electrospray ionization mode. RESULTS: The novel method fulfilled the requirements of the US Food and Drug Administration guidance on bioanalytical method validation. The calibration curve was linear over the 0.2-1000 ng/mL concentration range. The average recovery rate was 98.63 ± 4.55% (mean ± SD). The precision was below 6.05%, and the accuracy was within 12.96% for all quality control levels. The matrix effect varied between 103.33% and 134.61%. This assay was successfully applied to the measurement of plasma concentrations in 6 HCC patients receiving lenvatinib. CONCLUSIONS: A novel high-throughput UHPLC-MS/MS assay for quantification of lenvatinib in human plasma was successfully developed. This method can be applied to PPK analysis for patients receiving lenvatinib in the clinical setting.

Bioequivalence and Pharmacokinetic Evaluation of Two Oral Formulations of Regorafenib: An Open-Label, Randomised, Single-Dose, Two-Period, Two-Way Crossover Clinical Trial in Healthy Chinese Volunteers Under Fasting and Fed Conditions.

BACKGROUND: Regorafenib is an oral multi-kinase inhibitor approved for the treatment of solid tumours, but the pharmacokinetic profile of regorafenib in the Chinese population is unclear. OBJECTIVE: The aim of this study was to examine the pharmacokinetics, bioequivalence, and safety of two formulations of regorafenib 40 mg in healthy Chinese volunteers under fed and fasting conditions. METHODS: A single-centre, randomised, open-label, two-period, two-way crossover phase 1 trial was conducted by randomising a single oral dose of test (T) or reference (R, Stivarga®) regorafenib (40 mg) to healthy Chinese volunteers under both fasting and fed conditions (high-fat and high-calorie diet). Pharmacokinetic parameters were calculated using non-compartmental methods. Adverse events were recorded to assess drug safety. RESULTS: Sixty-six participants were enrolled for both fasting and fed treatments. The 90% CIs geometric least-square means of ratioT/R for regorafenib were completely contained within the equivalence margin of 80-125% under both fasting and fed conditions. Both formulations displayed similar and generally good safety profiles. CONCLUSION: Single oral dose of the T (40 mg) and R (40 mg) regorafenib was bioequivalent under fasting and fed conditions and had similar favourable safety profiles among healthy Chinese volunteers.

Phase I evaluation of lenvatinib and weekly paclitaxel in patients with recurrent endometrial, ovarian, fallopian tube, or primary peritoneal Cancer.

OBJECTIVES: To estimate the maximally tolerated dose (MTD) and describe toxicities associated with lenvatinib and weekly paclitaxel in patients with recurrent endometrial and platinum resistant epithelial ovarian cancer. METHODS: Using a 3 + 3 design patients were given weekly paclitaxel 80 mg/m2 IV day 1, 8, 15 and oral levantinib daily on a 28-day cycle. Lenvatinib dose levels were 8 mg, 12 mg, 16 mg, 20 mg. Toxicities were recorded using CTCAE v4.03 and response was determined with imaging after cycle 2, then every 3rd cycle, using RECIST 1.1 criteria. RESULTS: 26 patients were enrolled; 19 with ovarian cancer (14 high grade serous, 1 low grade serous, 2 clear cell, 1 endometrioid, and 1 carcinosarcoma), and 7 with endometrial cancer (3 serous, and 4 endometrioid). The MTD was established at lenvatinib 16 mg and weekly paclitaxel 80 mg/m2. Toxicities (all grades) occurring in ≥25% of patients included anemia, neutropenia, lymphopenia, mucositis, nausea, diarrhea, anorexia, hypertension, fatigue, proteinuria, epistaxis, hoarseness. Twenty-three patients were evaluable for response and PFS; 15 (65%) had a partial response, 7 (30%) stable, 1 (4%) progressive disease with an objective response rate of 65%; 71% in ovarian and 50% in endometrial cancer. Median progression free survival (PFS) is 12.4 months; 14.0 months in endometrial cancer, 7.2 months in ovarian cancer; 54% had a PFS > 6 months. The median duration of response for PR patients (n = 15) was 10.9 months. CONCLUSIONS: The regimen was tolerable with manageable side effects. Encouraging activity was observed in endometrial and ovarian cancer, and warrants further development.

Infigratinib Is a Reversible Inhibitor and Mechanism-Based Inactivator of Cytochrome P450 3A4.

Infigratinib (INF) is a promising selective inhibitor of fibroblast growth factor receptors 1-3 that has recently been accorded both orphan drug designation and priority review status by the US Food and Drug Administration for the treatment of advanced cholangiocarcinoma. Its propensity to undergo bioactivation to electrophilic species was recently expounded upon. However, other than causing aberrant idiosyncratic toxicities, these reactive intermediates may elicit mechanism-based inactivation of cytochrome P450 enzymes. In this study, we investigated the interactions between INF and the most abundant hepatic CYP3A. Our findings revealed that, apart from being a potent noncompetitive reversible inhibitor of CYP3A4, INF inactivated CYP3A4 in a time-, concentration- and NADPH-dependent manner with inactivator concentration at half-maximum inactivation rate constant, maximum inactivation rate constant, and partition ratio of 4.17 µM, 0.068 minute-1, and 41, respectively, when rivaroxaban was employed as the probe substrate. Coincubation with testosterone (alternative CYP3A substrate) or ketoconazole (direct CYP3A inhibitor) attenuated the rate of inactivation, whereas the inclusion of glutathione and catalase did not confer such protection. The lack of enzyme activity recovery after dialysis for 4 hours and oxidation with potassium ferricyanide, coupled with the absence of the characteristic Soret peak signature collectively substantiated that inactivation of CYP3A4 by INF was not mediated by the formation of quasi-irreversible metabolite-intermediate complexes but rather through irreversible covalent adduction to the prosthetic heme and/or apoprotein. Finally, glutathione trapping and high-resolution mass spectrometry experimental results unraveled two plausible bioactivation mechanisms of INF arising from the generation of a p-benzoquinonediimine and epoxide reactive intermediate. SIGNIFICANCE STATEMENT: The potential of INF to cause MBI of CYP3A4 was unknown. This study reports the reversible noncompetitive inhibition and irreversible covalent MBI of CYP3A4 by INF and proposes two potential bioactivation pathways implicating p-benzoquinonediimine and epoxide reactive intermediates, following which a unique covalent docking methodology was harnessed to elucidate the structural and molecular determinants underscoring its inactivation. Findings from this study lay the groundwork for future investigation of clinically relevant drug-drug interactions between INF and concomitant substrates of CYP3A4.

Infigratinib: First Approval.

Infigratinib (TRUSELTIQTM), a fibroblast growth factor receptor (FGFR)-specific tyrosine kinase inhibitor, is being co-developed by QED Therapeutics and Helsinn for the treatment of cholangiocarcinoma, urothelial carcinoma and other FGFR-driven conditions. Infigratinib was recently approved in the USA for the treatment of previously treated, unresectable locally advanced or metastatic cholangiocarcinoma with a FGFR2 fusion or other rearrangement as detected by a test approved by the US Food and Drug Administration. This article summarizes the milestones in the development of infigratinib leading to this first approval for advanced cholangiocarcinoma.

Comparative Pharmacokinetic Study of Forchlorfenuron in Adult and Juvenile Rats.

Forchlorfenuron (CPPU) is a plant growth regulator extensively used in agriculture. However, studies on CPPU pharmacokinetics are lacking. We established and validated a rapid, sensitive, and accurate liquid chromatography-mass spectrometry method for CPPU detection in rat plasma. CPPU pharmacokinetics was evaluated in adult and juvenile rats orally treated with 10, 30, and 90 mg/kg of the compound. The area under the plasma drug concentration-time curve from 0 to 24 h (AUC), at the final time point sampled (AUC0-t), and the maximum drug concentration of CPPU increased in a dose-dependent manner. The pharmacokinetic parameters AUC0-t and absolute bioavailability were higher in the juvenile rats than in adult rats. The mean residence time and AUC0-t of juvenile rats in the gavage groups, except for the 10 mg/kg dose, were significantly higher in comparison to those observed for adult rats (p < 0.001). The plasma clearance of CPPU in juvenile rats was slightly lower than that in the adult rats. Taken together, juvenile rats were more sensitive to CPPU than adult rats, which indicates potential safety risks of CPPU in minors.

Lentinan as a natural stabilizer with bioactivities for preparation of drug-drug nanosuspensions.

Lentinan is a natural ß-glucan with various bioactivities and is combined with chemotherapy drugs for cancer treatment. Regorafenib is an oral multi-kinase inhibitor approved by FDA for treatment of metastatic colorectal cancer, advanced hepatocellular carcinoma, and metastatic gastrointestinal stromal tumors. Regorafenib has poor water solubility and multiple toxicities. We report drug-drug nanosuspensions of regorafenib and lentinan. Results of dynamic light scattering and scanning electron microscopy showed that the mean particle size of the regorafenib-lentinan nanosuspensions was approximately 200 nm and was uniformly distributed. Transmission electron microscopy findings indicated that lentinan stabilized the nanosuspensions by steric manner. Hydrogen bonds and hydrophobic interactions were found between regorafenib and lentinan by molecular dynamics simulation. The results of cytotoxicity assay and pharmacokinetics study in rats showed that the regorafenib-lentinan nanosuspensions reduced the toxicity and enhanced the in vitro anticancer activity and oral bioavailability of regorafenib. Lentinan as a natural stabilizer has the potential using for drug nanosuspensions. Drug-drug nanosuspensions are a new form of combination therapies that can reduce the number of drugs taken by patients and improve their compliance.

Phase 1 dose-escalation and pharmacokinetic study of regorafenib in paediatric patients with recurrent or refractory solid malignancies.

BACKGROUND: This phase 1 study evaluated safety, pharmacokinetics (PK), maximum tolerated dose (MTD), and antitumour activity of regorafenib in paediatric patients with solid tumours. PATIENTS AND METHODS: Patients (aged 6 months to <18 years) with recurrent/refractory solid tumours received oral regorafenib once daily for 3 weeks on/1 week off. The starting dose (60 mg/m2) was derived from an adult physiology-based PK model and scaled to children; dose escalation was followed by safety expansion of the MTD cohort. Treatment-emergent adverse events (TEAEs) were evaluated using National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Regorafenib PK was evaluated using a population PK model. RESULTS: Forty-one patients (median age 13 years) received regorafenib (four cohorts: 60-93 mg/m2). Five of 23 evaluable patients experienced dose-limiting toxicities (Grade 4 thrombocytopenia, Grade 3 maculopapular rash, pyrexia, hypertension, and exfoliative dermatitis [each n = 1]). The MTD was defined as 82 mg/m2. The most common Grade ≥3 drug-related TEAE was thrombocytopenia (10%). The incidence and severity of hypertension, diarrhoea, fatigue, hypothyroidism, and hand-foot skin reaction were lower than reported in adults. Regorafenib exposure increased with dose, with substantial overlap because of moderate-to-high interpatient variability. One patient with rhabdomyosarcoma experienced an unconfirmed partial response; 15 patients had stable disease, five for >16 weeks. CONCLUSIONS: The recommended phase 2 dose of single-agent regorafenib in paediatric patients with solid malignancies is 82 mg/m2. Regorafenib demonstrated acceptable tolerability and preliminary antitumour activity, supporting further investigation in paediatric patients. CLINICAL TRIAL NUMBER: NCT02085148.

Pharmacokinetics of the oral multikinase inhibitor regorafenib and its association with real-world treatment outcomes.

Purpose Despite the established activity of regorafenib in metastatic colorectal cancer (CRC), gastrointestinal stromal tumor (GIST), and hepatocellular carcinoma (HCC), its toxicity profile has limited clinical use. We aimed to evaluate the pharmacokinetics of regorafenib and its active metabolites M-2/M-5, and to clarify the relationships between total drug-related exposure and clinical outcomes in real-world practice. Methods Blood samples at steady state were obtained during Cycle 1 from patients treated with regorafenib. Plasma concentrations of regorafenib and its metabolites were measured by liquid chromatography-tandem mass spectrometry. The efficacy and safety endpoints were progression-free survival (PFS) and dose-limiting toxicities (DLTs), respectively. The exposure-response relationships were assessed. Results Thirty-four Japanese patients with advanced cancers were enrolled (CRC, n = 26; GIST and HCC, each n = 4). Nine patients started regorafenib treatment at the recommended dose of 160 mg once daily (3 weeks on / 1 week off), while the other patients received a reduced starting dose to minimize toxicities. The median PFS was significantly longer in patients achieving total trough concentrations (Ctrough) of regorafenib and M-2/M-5 ≥2.9 µg/mL than those who did not (112 vs. 57 days; p = 0.044). Furthermore, the cumulative incidence of DLTs during the first 2 cycles was significantly higher in patients with summed Ctrough levels ≥4.3 µg/mL than in others (p = 0.0003). Conclusions Dose titration of regorafenib to achieve drug-related Ctrough levels between 2.9 and 4.3 µg/mL in Cycle 1 may improve efficacy and safety, warranting further investigation in a larger patient population.Clinical trial registry: Not applicable.

Associations among plasma concentrations of regorafenib and its metabolites, adverse events, and ABCG2 polymorphisms in patients with metastatic colorectal cancers.

PURPOSE: The association between the pharmacokinetics and pharmacodynamics of regorafenib, a multiple tyrosine kinase inhibitor, remains unclear. This study assessed the trough plasma concentrations (Ctrough) of regorafenib and its N-oxide (M2) and N-oxide/desmethyl (M5) metabolites, and evaluated the associations among these levels, adverse events, and pharmacokinetic-related genetic polymorphisms in patients with metastatic colorectal cancer. METHODS: The Ctrough levels of regorafenib and its metabolites were assessed in a single-center, prospective, observational study, 7 days after the initial treatment. The correlation between those values and adverse events was then examined. In addition, the genetic polymorphisms of ABCG2, SLCO1B1, and UGT1A9 were determined and evaluated for associations with the levels of regorafenib, M2, and M5. RESULTS: We analyzed 43 patients who received regorafenib 40-120 mg/day; among them, 35 patients started at 120 mg/day. With regard to bilirubin increase, the Ctrough values of regorafenib were significantly higher in the group with grade ≥ 2 than in groups with grades 0 and 1 (p = 0.010). The M5 Ctrough levels were significantly associated with the severity of hypertension or rash (p < 0.05). In a multivariate analysis, the M5 Ctrough values and age were significant predictors of severe rash. Lastly, significant differences were noted in the M5 concentration-to-dose ratio values between the patients with ABCG2 421A/A and ABCG2 421C/A or C/C polymorphisms (p = 0.035). CONCLUSION: This study showed that the Ctrough of regorafenib was associated with bilirubin increase, and also clarified for the first time that the Ctrough of M5 was significantly correlated with hypertension and severe rash.

Evaluation of the impact of renal impairment on the pharmacokinetics of glasdegib in otherwise healthy volunteers.

PURPOSE: Glasdegib is being developed for indications in myeloid malignancies. The effect of renal impairment on the pharmacokinetics (PK) of a single, oral, 100-mg glasdegib dose under fasted conditions was assessed. METHODS: Open-label, parallel-group study (NCT03596567). Participants of good general health were selected and categorized, based on their estimated glomerular filtration rate, into normal (≥ 90 mL/min), moderate (≥ 30 to < 60 mL/min), or severe (< 30 mL/min) renal impairment groups. Blood samples were collected up to 120 h post-dose. PK exposure parameters were calculated using non-compartmental analysis. RESULTS: All 18 participants completed the study. Respectively, ratios of adjusted geometric means (90% confidence interval) for glasdegib area under the curve from time 0 to infinity and peak plasma concentration versus normal participants were 205% (142-295%) and 137% (97-193%) in the moderate group, and 202% (146-281%) and 120% (77-188%) in the severe group. Glasdegib median time to peak plasma concentration was 2.0 h in both impairment groups and 1.5 h in the normal group. Mean oral clearance was decreased by approximately 50% in both renal impairment groups compared with the normal group. The plasma-free fraction of glasdegib was not altered by renal impairment. Five all-causality adverse events were reported in three participants; two were considered treatment-related. CONCLUSION: The similar changes in exposure observed for participants with renal impairment, coupled with the known safety data from clinical experience, suggest that a lower starting dose of glasdegib may not be required for moderate or severe renal impairment. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03596567 (started May 17, 2018).

Pharmacokinetic study of lenvatinib in Chinese patients with solid tumors.

Aim: To assess the pharmacokinetics of once-daily oral lenvatinib 24 mg in Chinese patients. Material & methods: Patients had any solid tumor (except hepatocellular carcinoma) that was resistant to standard antitumor therapies or for which no appropriate treatment was available. Results: Twelve patients were enrolled. Maximum plasma concentrations of lenvatinib were observed at 2 and 4 h (median) after single and multiple doses (day 15), respectively. Steady state was achieved within 8 days. The geometric mean maximum observed concentration at steady state was 258 ng/ml (coefficient of variance: 49.2%); and the geometric mean area under the concentration-time curve from zero to 24 h at steady state was 3090 ng•h/ml (coefficient of variance: 44.7%). No accumulation was seen after 15 days. Conclusion: Lenvatinib pharmacokinetic data in Chinese patients are consistent with data in multinational trials, supporting usage of the 24-mg dose. Clinical trial registration: NCT03009292 (ClinicalTrials.gov).

Pharmacodynamic analysis of hypertension caused by lenvatinib using real-world postmarketing surveillance data.

Lenvatinib is a tyrosine kinase inhibitor of the vascular endothelial growth factor receptor used against nonoperative thyroid cancer; however, hypertension is a major dose-limiting side effect. In this study, hypertension caused by lenvatinib was described through a novel population pharmacodynamic model using postmarketing surveillance data obtained in Japan. The model consists of two maximum effect model components based on the (1) concentration of lenvatinib in plasma and (2) cumulative area under the curve of lenvatinib. In addition, antihypertensive drug of either an angiotensin-converting enzyme inhibitor/angiotensin receptor blocker or calcium channel blocker accounted for by lowering effect on diastolic blood pressure. Based on virtual simulations, the combination of antihypertensive drug and dose adjustment of lenvatinib showed a reduction in the probability of grade greater than or equal to 3 hypertension. The present model provides useful guidance in managing hypertension during treatment with lenvatinib in the real-world setting.

Clinical and Model-Based Evaluation of the Effect of Glasdegib on Cardiac Repolarization From a Randomized Thorough QT Study.

Glasdegib is a potent, selective oral inhibitor of the Hedgehog signaling pathway. This phase 1 double-blind thorough QT study (NCT03162900) evaluated the effects of glasdegib on QTc interval. The study enrolled 36 healthy volunteers to receive a single dose of 150 mg glasdegib (representing a therapeutic dose), 300 mg glasdegib (representing a supratherapeutic dose), 400 mg moxifloxacin (positive control), or placebo under fasted conditions. The study demonstrated that therapeutic and supratherapeutic doses of glasdegib had no significant effect on QTc interval; the upper bound of the 2-sided 90% confidence intervals (CIs) for all time-matched least-squares mean differences in QT interval corrected using Fridericia's formula (QTcF) between glasdegib and placebo was below the prespecified criterion of 20 milliseconds (Food and Drug Administration correspondence reviewed and accepted). Based on an exposure-response analysis, glasdegib was determined not to have a meaningful effect on heart rate (change in RR interval). The mean (90%CI) model-derived baseline and placebo-adjusted QTcF at the average maximum observed concentration values corresponding to therapeutic and supratherapeutic glasdegib doses was 7.3 milliseconds (6.5-8.2 milliseconds) and 13.7 milliseconds (12.0-15.5 milliseconds), respectively. Together these results demonstrated that following therapeutic and supratherapeutic glasdegib dosing, the change in QTc from baseline was well below the 20-millisecond threshold of clinical concern in oncology.