Background and Objectives Lorlatinib is approved (100 mg once daily [QD]) for the treatment of patients with anaplastic lymphoma kinase- (ALK) positive metastatic non-small cell lung cancer. This study evaluated the impact of varying degrees of renal impairment on the safety and pharmacokinetics of lorlatinib. Methods Participants were assigned to mild, moderate, and severe renal impairment groups and to a matching normal renal function group based on absolute estimated glomerular filtration rate (eGFR, based on the Modification of Diet in Renal Disease equation and adjusted for body surface area [BSA]) and were evaluated for pharmacokinetics and safety. Results A total of 29 participants (5 with severe renal impairment; 8 each with moderate and mild impairment and normal renal function) were enrolled and received a single dose of lorlatinib 100 mg. One of the participants with severe renal impairment had end-stage renal disease with a baseline absolute eGFR of 10.3 mL/min. No serious adverse events (AEs) were reported. Eighteen AEs, all mild or moderate in severity, were reported by 12 participants (5, 2, 4, and 1 in the normal, mild, moderate, and severe groups, respectively). Area under the plasma concentration–time profile from time zero extrapolated to infinity (AUCinf) for lorlatinib was increased by 4%, 19%, and 41% in the mild, moderate, and severe renal impairment groups, respectively, compared with the normal renal function cohort. Conclusion Lorlatinib 100 mg was well tolerated. As participants with mild and moderate renal impairment did not experience clinically meaningful increases in lorlatinib exposure, no lorlatinib dose adjustment is recommended in these populations. Patients with severe renal impairment are recommended to reduce the starting dose of lorlatinib from 100 mg QD to 75 mg QD. Clinicaltrials.gov identifier NCT03542305 (available May 31, 2018 on clinicaltrials.gov)
Introduction: Dacomitinib is an epidermal growth factor receptor (EGFR) inhibitor approved for the treatment of metastatic non-small cell lung cancer (NSCLC) in the first line in patients with EGFR activating mutations. Dacomitinib is taken orally once daily at 45 mg with or without food, until disease progression or unacceptable toxicity occurs. Oncology patients often can develop gastroesophageal reflux disease (GERD), which may require management with an acid-reducing agent. Proton pump inhibitors (PPIs), such as rabeprazole, inhibit sodium-potassium adenosine triphosphatase (H+/K+-ATPase) pumps that stimulate acid secretion in the stomach and have a prolonged pharmacodynamic effect that extends beyond 24 h post-administration. The aim of this work was to characterize the absorption of dacomitinib via modeling with a particular interest in quantifying the impact of rabeprazole on the pharmacokinetics (PK) of dacomitinib. Materials and Methods: The pooled dataset consisted of five clinical pharmacology healthy volunteer studies, which collected serial pharmacokinetic concentration-time profiles of dacomitinib. Non-linear mixed effects modeling was carried out to characterize dacomitinib pharmacokinetics in the presence and absence of the concomitant use of a PPI, rabeprazole. Several absorption models, some more empirical, and some more physiologically based, were tested: transit compartment, first-order absorption with and without lag time, and variations of combined zero- and first-order absorption kinetics models. Results: The presence of a PPI was a significant covariate affecting the extent (F) and rate (ka) of dacomitinib absorption, as previously reported in the dedicated clinical study. A transit compartment model was able to best describe the absorption phase of dacomitinib.
1 May 2020 in The Journal of Clinical Pharmacology
Glasdegib is an inhibitor of the Hedgehog pathway recently approved in the United States for the treatment of acute myeloid leukemia. A population pharmacokinetic analysis was conducted to characterize the kinetic behavior of glasdegib and its sources of variability (covariates) by utilizing data from 269 patients with cancer treated with oral glasdegib doses ranging from 5 to 640 mg/d. Nonlinear mixed-effects modeling was conducted using NONMEM (v.7.3) and Perl-speaks NONMEM (v.4.2.0). The estimated apparent total clearance, apparent central volume of distribution, and apparent peripheral volume of distribution were 6.27 L/h, 3.32 L, and 279.2 L, respectively. Age, sex, race, and hepatic function were not significant covariates on glasdegib pharmacokinetic parameters. Baseline body weight, percentage bone marrow blasts, creatinine clearance, and use of moderate or strong cytochrome P450 3A inhibitors were statistically significant covariates on apparent total clearance; however, the magnitude of the effects was not considered clinically meaningful.
29 June 2018 in Journal of Oncology and Cancer Research
Purpose: Glasdegib, an oral inhibitor of the Hedgehog signaling pathway, is approved in the United States in combination with low-dose cytarabine (LDAC) to treat patients with newly diagnosed acute myeloid leukemia (AML) ineligible to receive intensive chemotherapy. This population pharmacokinetic/pharmacodynamic analysis characterized the time course of survival with glasdegib + LDAC relative to LDAC alone, and explored whether the differences in glasdegib exposure at the clinical dose of 100 mg once daily (QD) significantly affected overall survival (OS). Methods: Data from the BRIGHT AML 1003 trial in patients with AML were included in treatment–response (glasdegib + LDAC, n = 78; LDAC alone, n = 38) and exposure–response (glasdegib + LDAC, n = 75) analyses. Results: The analyses demonstrate that patients treated with glasdegib + LDAC (vs LDAC alone) at any time point during the study period were 58% less likely to die, translating to prolonging of median OS by ~ 5 months (hazard ratio 0.42 [95% confidence interval 0.28–0.66]). Variability in glasdegib exposures did not impact the risk of death. Additionally, potential covariates such as patient demographics, prior treatment with a hypomethylating agent, baseline safety laboratory values, and disease characteristics, did not impact the probability of OS. Conclusion: Together these results confirm that glasdegib + LDAC treatment (vs. LDAC alone) is associated with a significant survival benefit in patients with newly diagnosed AML, and that variability in glasdegib doses (e.g., for dose reductions) and exposures do not compromise the survival benefit of glasdegib 100 mg QD. Clinical Trial number: NCT01546038.