Evaluation of the Relationship of Glasdegib Exposure and Safety End Points in Patients With Refractory Solid Tumors and Hematologic Malignancies
JOURNAL OF CLINICAL PHARMACOLOGY
Authors: Ruiz-Garcia, Ana; Shaik, Naveed; Lin, Swan; Jamieson, Catriona; Heuser, Michael; Chan, Geoffrey
Abstract
Glasdegib is approved for treating acute myeloid leukemia in elderly patients at 100 mg once daily in combination with low-dose cytarabine. Exposure-efficacy analysis showed that the survival benefit of glasdegib was not glasdegib exposure-dependent. The relationship between glasdegib exposure and adverse event (AE) cluster terms of clinical concern was explored in this analysis. The incidence and severity ofdysgeusia,muscle spasms,renal toxicity, andQT interval prolongedwas modeled using ordinal logistic regression. AEs were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03). Estimated pharmacokinetic parameters were used to derive glasdegib exposure metrics. Demographic characteristics, disease factors, and other variables of interest as potential moderators of safety signals were evaluated. Clinical trial data from patients who received single-agent glasdegib (N = 70; 5-640 mg once daily); or glasdegib (N = 202, 100-200 mg once daily) with low-dose cytarabine, decitabine, or daunorubicin and cytarabine were analyzed. Glasdegib exposure was statistically significantly associated with the cluster term safety end pointsdysgeusia,muscle spasms,renal toxicity, andQT interval prolonged. The impact of age onmuscle spasmsand baseline body weight and creatinine clearance onrenal toxicityhelped explain the AE grade distribution. At the 100 mg once daily clinical dose, the predicted probabilities of the highest AE grade were 11.3%, 6.7%, 7.7%, and 2.5% fordysgeusia,muscle spasms,renal toxicity, andQT interval prolonged, respectively. Overall, the predicted probability of developing an AE of any severity for these safety end points was low. Therefore, no starting dose adjustments are recommended for glasdegib based on the observed safety profile.
Novel Programming Features Help Alleviate Subthalamic Nucleus Stimulation-Induced Side Effects
MOVEMENT DISORDERS
Authors: Dayal, Viswas; De Roquemaurel, Alexis; Grover, Timothy; Ferreira, Francisca; Salazar, Maricel; Milabo, Catherine; Candelario-McKeown, Joseph; Zrinzo, Ludvic; Akram, Harith; Limousin, Patricia; Foltynie, Thomas
Abstract
Background: Subthalamic nucleus deep brain stimulation (STN-DBS) is a widely used treatment for Parkinson's disease (PD) patients with motor complications, but can result in adverse effects (AEs) in a significant proportion of treated patients. The use of novel programming features including short pulse width (PW) and directional steering in alleviating stimulation-induced AEs has not been explored. Objective: To determine if programming with short PW, directional steering, or the combination of these novel techniques can improve stimulation-induced dysarthria, dyskinesia, and pyramidal AEs. Methods: Thirty-two consecutive PD patients who experienced reversible AEs of STN-DBS had optimization of their settings using either short PW, directional steering, or the combination, while ensuring equivalent control of motor symptoms. Pairwise comparisons of pre- and post-optimization adverse effect ratings were made. Patients were left on the alternative setting with the greatest benefit and followed up at 6 months. Modeling of volume of tissue activated (VTA) and charge per pulse (Qp) calculations were used to explore potential underlying mechanisms of any differences found. Results: There were significant improvements in stimulation-induced dysarthria, dyskinesia, and pyramidal side effects after optimization. At 6 months, mean AE ratings remained significantly improved compared to pre-optimization ratings. Different patterns of shift in VTA for each AE, and Qp could be used to explain improvements using novel techniques. Conclusions: Stimulation-induced dysarthria, dyskinesia, and pyramidal AEs induced by STN-DBS can be improved by using novel programming techniques. These represent additional tools to conventional methods that can be used to address these AEs. (c) 2020 The Authors.Movement Disorderspublished by Wiley Periodicals LLC. on behalf of International Parkinson and Movement Disorder Society.