Model-Informed Selection of the Recommended Phase III Dose of the Inhibitor of Apoptosis Protein Inhibitor, Xevinapant, in Combination with Cisplatin and Concurrent Radiotherapy in Patients with Locally Advanced Squamous Cell Carcinoma of the Head and Neck.

Xevinapant, an oral inhibitor of apoptosis protein (IAP) inhibitor, demonstrated efficacy in combination with chemoradiotherapy in a randomized phase II study (NCT02022098) in patients with locally advanced squamous cell carcinoma of the head and neck at 200 mg/day on days 1-14 of a 3-week cycle. To confirm 200 mg/day as the recommended phase III dose (RP3D), we integrated preclinical, clinical, pharmacokinetic/pharmacodynamic (PK/PD), and exposure-response modeling results. Population PK/PD modeling of IAP inhibition in peripheral blood mononuclear cells in 21 patients suggested the pharmacologically active dose range was 100-200 mg/day, with a trend for more robust inhibition at the end of the dosing interval at 200 mg/day based on an indirect response model. Additionally, the unbound average plasma concentration at 200 mg/day was similar to that associated with efficacy in preclinical xenograft models. Logistic regression exposure-response analyses of data from 62 patients in the phase II study showed exposure-related increases in probabilities of locoregional control at 18 months (primary end point), overall response, complete response, and the radiosensitization mechanism-related composite safety end point "mucositis and/or dysphagia" (P < 0.05). Exposure-response relationships were not discernible for 12 of 13 evaluated safety end points, incidence of dose reductions, and time to first dose reduction. Quantitative integration of all available data, including model-derived target inhibition profiles, positive exposure-efficacy relationships, and lack of discernible exposure-safety relationships for most safety end points, supports selection of xevinapant 200 mg/day on days 1-14 of a 3-week cycle as the RP3D, allowing for successive dose reductions to 150 and 100 mg/day to manage adverse events.

Population Pharmacokinetics of Mivavotinib (TAK-659), a Dual Spleen Tyrosine Kinase and FMS-Like Tyrosine Kinase 3 Inhibitor, in Patients With Advanced Solid Tumors or Hematologic Malignancies.

Mivavotinib (TAK-659), an orally administered, small-molecule, dual inhibitor of spleen tyrosine kinase and FMS-like tyrosine kinase 3 (SYK/FLT3), is under development for the treatment of patients with advanced malignancies. In this analysis, we evaluated the population pharmacokinetics (PK) of mivavotinib and its sources of variability (covariates) in adult patients with advanced solid tumors, or relapsed/refractory B-cell lymphomas or acute myeloid leukemia, using pooled data from 159 patients enrolled in 2 phase 1/2 clinical studies. A 2-compartment model with first-order linear elimination and a first-order absorption rate (and associated lag time) adequately described the PK of mivavotinib in this patient population. The population estimates of apparent clearance (CL/F) and apparent central compartment volume (Vc /F) were 31.6 L/h and 893 L, respectively, resulting in a half-life of ≈20 hours. In the final model, creatinine clearance was included as a covariate of CL/F, and sex as a covariate of Vc /F. Simulations showed that steady-state exposure to mivavotinib increased with decreasing renal function. Expanding eligibility by enrolling patients with moderate renal impairment in phase 1 increased the diversity of patients in early trials and allowed the model to inform dose adjustment in patients with moderate renal impairment in future trials. In addition, simulations showed median steady-state trough concentration of mivavotinib following 70 mg twice daily and 160 mg daily dosing to be commensurate with 100 ng/mL, the level leading to >90% FLT3 inhibition per ex vivo plasma immune assays and considered a potential exposure threshold required for FLT3-driven efficacy.

Assessment of Effects of Investigational TAK-931, an Oral Cell Division Cycle 7 Kinase Inhibitor on the QTc Intervals in Patients With Advanced Solid Tumors.

TAK-931, a novel, selective, small-molecule inhibitor of cell division cycle 7 has been investigated in multiple clinical trials in patients with advanced solid tumors. An integrated analysis using data from 2 clinical studies assessed effects of TAK-931 on electrocardiogram QT intervals and heart rate (HR). Pharmacokinetic samples and matched triplicate electrocardiogram data were collected in 48 patients with cancer receiving oral administration of TAK-931 50 or 80 mg once daily. The relationships between TAK-931 plasma concentrations and the HR-corrected QT interval via Fridericia (QTcF) or population (QTcP) and HR were analyzed using linear mixed-effects models with fixed effects for day and time. At the geometric mean maximum TAK-931 plasma concentrations after administration of 50 mg, an HR change of 3.40 beats per minute (90%CI, 1.86-4.80) was predicted. Change in QTcF of -3.41 milliseconds (90%CI, -5.77 to -1.17) and QTcP of -2.02 milliseconds (90%CI, -4.15 to 0.0679) were estimated, indicating there was no effect of TAK-931 on the QT intervals at a recommended phase 2 dose of 50 mg once daily for 14 days in a 21-day cycle.

Population Pharmacokinetics of TAK-931, a Cell Division Cycle 7 Kinase Inhibitor, in Patients With Advanced Solid Tumors.

A population pharmacokinetic (PK) analysis was conducted to characterize sources of interpatient variability on the PK of TAK-931, a cell division cycle 7 kinase inhibitor, in adult patients with advanced solid tumors using data from 198 patients who received oral TAK-931 over the range of 30 to 150 mg once daily in multiple dosing schedules in 2 phase 1 and 1 phase 2 clinical studies. A 2-compartment model with 2 transit compartments describing the absorption and first-order linear elimination adequately described the PK of TAK-931. The apparent oral clearance (CL/F) of TAK-931 was estimated to be 38 L/h, and the terminal half-life was estimated to be approximately 6 hours. Creatinine clearance (CrCL) was identified as a covariate on CL/F, and body weight as a covariate on CL/F, apparent central volume of distribution, and apparent intercompartmental clearance. Simulations using the final model indicated that the effect of CrCL (≥35 mL/min) or body weight (29.8-127 kg) on TAK-931 systemic exposures was not considered clinically meaningful, suggesting that no dose adjustments were necessary to account for body weight or renal function (CrCL ≥35 mL/min). Sex, age (36-88 years), race, and mild hepatic impairment had no impact on the CL/F of TAK-931. Taken together, the population PK analysis supports the same starting dose of TAK-931 in Asian and Western cancer patients in a global setting.

Population Pharmacokinetic and Pharmacodynamic Analysis of GLPG1690, an Autotaxin Inhibitor, in Healthy Volunteers and Patients with Idiopathic Pulmonary Fibrosis.

BACKGROUND AND OBJECTIVES: GLPG1690 is an autotaxin inhibitor in development for the treatment of idiopathic pulmonary fibrosis. Several publications suggested a role of autotaxin in the control of disease-affected lung function and of lysophosphatidic acid in lung remodeling processes. The aim of the current article was to describe the exposure-response relationship of GLPG1690 and further develop a rational basis to support dose selection for clinical trials in patients with idiopathic pulmonary fibrosis. METHODS: Two trials were conducted in healthy volunteers: in the first trial, GLPG1690 was administered as single doses from 20 mg up to 1500 mg, and subsequently in multiple daily doses of 300-1000 mg. In a second trial, the interaction of rifampin with 600 mg of GLPG1690 was evaluated. A third trial was conducted in patients with idiopathic pulmonary fibrosis administered 600 mg of GLPG1690 once daily for 12 weeks. The exposure-response (lysophosphatidic acid C18:2 reduction) relationship of GLPG1690 was first described using non-linear mixed-effects modeling and the model was subsequently deployed to simulate a lysophosphatidic acid C18:2 reduction as a biomarker of autotaxin inhibition in the dose range from 50 to 1000 mg once or twice daily. RESULTS: The population pharmacokinetics and lysophosphatidic acid C18:2 response of GLPG1690 were adequately described by a combined population pharmacokinetic and pharmacokinetic/pharmacodynamic model. Dose, formulation, rifampin co-administration, health status (healthy volunteer vs. patient with idiopathic pulmonary fibrosis), and baseline lysophosphatidic acid C18:2 were identified as covariates in the model. The effect of dose on systemic clearance indicated that GLPG1690 followed a more than dose-proportional increase in exposure over the simulated dose range of 50-1000 mg once daily. Model-based simulations showed reductions in lysophosphatidic acid C18:2 of at least 80% with doses greater or equal to 200 mg once daily. CONCLUSION: Based on these results, 200 and 600 mg once-daily doses were selected for future clinical trials in patients with idiopathic pulmonary fibrosis.

Pharmacokinetics and Pharmacokinetic/Pharmacodynamic Modeling of Filgotinib (GLPG0634), a Selective JAK1 Inhibitor, in Support of Phase IIB Dose Selection.

BACKGROUND AND OBJECTIVES: Filgotinib (GLPG0634) is a selective inhibitor of Janus kinase 1 (JAK1) currently in development for the treatment of rheumatoid arthritis and Crohn's disease. While less selective JAK inhibitors have shown long-term efficacy in treating inflammatory conditions, this was accompanied by dose-limiting side effects. Here, we describe the pharmacokinetics of filgotinib and its active metabolite in healthy volunteers and the use of pharmacokinetic-pharmacodynamic modeling and simulation to support dose selection for phase IIB in patients with rheumatoid arthritis. METHODS: Two trials were conducted in healthy male volunteers. In the first trial, filgotinib was administered as single doses from 10 mg up to multiple daily doses of 200 mg. In the second trial, daily doses of 300 and 450 mg for 10 days were evaluated. Non-compartmental analysis was used to determine individual pharmacokinetic parameters for filgotinib and its metabolite. The overall pharmacodynamic activity for the two moieties was assessed in whole blood using interleukin-6-induced phosphorylation of signal-transducer and activator of transcription 1 as a biomarker for JAK1 activity. These data were used to conduct non-linear mixed-effects modeling to investigate a pharmacokinetic/pharmacodynamic relationship. RESULTS: Modeling and simulation on the basis of early clinical data suggest that the pharmacokinetics of filgotinib are dose proportional up to 200 mg, in agreement with observed data, and support that both filgotinib and its metabolite contribute to its pharmacodynamic effects. Simulation of biomarker response supports that the maximum pharmacodynamic effect is reached at a daily dose of 200 mg filgotinib. CONCLUSION: Based on these results, a daily dose range up to 200 mg has been selected for phase IIB dose-finding studies in patients with rheumatoid arthritis.

Characterizing systemic exposure of inhaled drugs: application to the long-acting ß2-agonist PF-00610355.

BACKGROUND AND OBJECTIVES: PF-00610355 is an orally inhaled long-acting ß2-adrenoreceptor agonist that is being developed for the once-daily treatment of chronic obstructive pulmonary disease (COPD). The pharmacological effect is exerted in the lungs. However, systemic exposure of PF-00610355 is expected to be responsible for certain drug-related adverse effects. This analysis characterizes PF-00610355 using an integrated analysis of systemic exposure, across trials and patient populations. METHODS: A total of 6,107 samples of PF-00610355 plasma concentration, collected in 264 subjects from eight studies in healthy volunteers, asthma, and COPD patients, were analyzed using non-linear mixed-effects models. Model-based mean (95 % CI) exposure profiles for a range of PF-00610355 doses in COPD patients were simulated. RESULTS: PF-00610355 exposure profiles were described by a three-compartment disposition model with first-order absorption through a transit compartment. Patient status, inhalation device, and demographic factors were found to influence systemic drug exposure. Relative fine particle dose had a minor effect, whereas no effect of baseline lung function on the systemic exposure was found. An implicit method to address pharmacokinetic variability between occasions of drug intake yielded similar results as the established explicit method, yet in a much more efficient way. CONCLUSION: The estimated systemic pre-dose and maximum PF-00610355 plasma concentration was 23 and 38 % in COPD patients compared to healthy volunteers, respectively. The analysis illustrated the value of an integrated pharmacokinetic analysis to address specific challenges in the clinical development of long-/ultra-long-acting ß2-agonists and inhaled compounds in general, both in relation to selecting a safe starting dose in patients, but also in understanding exposure and systemic safety information across different patient populations and different inhalation devices/formulations.

Predicted heart rate effect of inhaled PF-00610355, a long acting ß-adrenoceptor agonist, in volunteers and patients with chronic obstructive pulmonary disease.

AIM: To assess the cardiovascular effects of a new inhaled long-acting ß-adrenoceptor agonist PF-00610355 in COPD patients. METHODS: Thirteen thousand and sixty-two heart rate measurements collected in 10 clinical studies from 579 healthy volunteers, asthma and COPD patients were analyzed. The relationship between heart rate profiles and predicted plasma concentration profiles, patient status, demographics and concomitant medication was evaluated using non-linear mixed-effects models. The median heart rate increase in COPD patients for doses of PF-00610355 up to 280 µg once daily was simulated with the final pharmacokinetic/pharmacodynamic (PKPD) model. RESULTS: An Emax model accounting for delayed on-and off-set of the PF-00610355-induced change in heart rate was developed. The predicted potency in COPD patients was three-fold lower compared with healthy volunteers, while no difference in maximum drug effect was identified. Simulations suggested a maximum placebo-corrected increase of 2.7 (0.90-4.82) beats min(-1) in COPD patients for a PF-00610355 dose of 280 µg once daily, with 19% subjects experiencing a heart rate increase of more than 20 beats min(-1) compared with 8% in the placebo group. CONCLUSIONS: This PKPD analysis supports the clinical observation that no relevant effects of PF-00610355 on heart rate in COPD patients should be expected for doses up to 280 µg once daily.