Search

Aim: Chemotherapy‐induced peripheral neuropathy (CIPN) is a major toxicity limiting the use of nab‐paclitaxel (Nab‐P) in treating patients with pancreatic cancer. The aim of this study was to identify the factors affecting CIPN using patient‐reported outcome measures and the minimally invasive volumetric absorptive microsampling (VAMS) technique. Methods: The maximum concentrations of paclitaxel (Cmax) were measured from 81 VAMS samples collected from 44 participants with pancreatic cancer. The association between CIPN development and demographic, clinical and pharmacokinetic factors was determined using univariable and multivariable logistic regression. The association between CIPN severity and the factors was evaluated using Spearman's rank correlation. The impact of Cmax and the number of treatment cycles on the severity was assessed using multivariable linear regression. Results: The development of CIPN was significantly associated with cumulative dose (odds ratio 1.005, 95% confidence interval [CI] 1.003‐1.007), treatment cycles (3.47, 2.25‐5.85), alkaline phosphate (0.992, 0.985‐0.998) and age (1.092, 1.020‐1.179), with an area under the receiver operating characteristic curve of 0.89 (95% CI 0.83‐0.95). The severity of CIPN significantly worsened with increasing cumulative dose (coefficient 0.58, 95% CI 0.44‐0.69), treatment cycles (0.57, 0.44‐0.68) and age (0.18, 0.00‐0.35). The severity of CIPN was predictable from treatment cycles (P =.0002) and Cmax (P =.01). Conclusion: The higher the cumulative dose of Nab‐P, treatment cycles and age, the more frequently and severely do the patients experience CIPN. In predicting the severity of CIPN using Cmax, minimally invasive VAMS is a feasible alternative to venous blood sampling. [ABSTRACT FROM AUTHOR]

Background: To assess the cardiovascular (CV) risk associated with the use of incretin-based therapy in adult patients with type 2 diabetes mellitus (T2DM) primary prevention group with low CV risks. Methods: The clinical studies on incretin-based therapy published in medical journals until August 2014 were comprehensively searched using MEDLINE, EMBASE and CENTRAL with no language restriction. The studies were systemically reviewed and evaluated for CV risks using a meta-analysis approach and where they meet the following criteria: clinical trial, incidence of predefined CV disease, T2DM with no comorbidities, age > 18 years old, duration of at least 12 weeks, incretin-based therapy compared with other antihyperglycaemic agents or placebo. Statistical analyses were performed using a Mantel-Haenszel (M-H) test. The odds ratios (OR) and their 95% confidence interval (CI) were estimated and displayed for comparison. Results: A total of 75 studies comprising 45,648 patients with T2DM were selected. The pooled estimate demonstrated no significance in decreased CV risk with incretin-based therapy versus control (M-H OR, 0.90; 95% CI, 0.81–1.00). Conclusions: This meta-analysis suggests that incretin-based therapy show no significant protective effect on CV events in T2DM primary prevention group with low CV risks. Prospective randomized controlled trials are required to confirm the results of this analysis. [ABSTRACT FROM AUTHOR]

Purpose: Vactosertib, a novel inhibitor of transforming growth factor-β type Ι receptor, is under development for the treatment of various cancers. The objective of this study was to characterize the population pharmacokinetics of vactosertib in patients with solid tumors.Methods: Vactosertib population pharmacokinetics was assessed by nonlinear mixed-effects modelling of plasma concentration-time data obtained from a first-in-human phase 1 trial conducted in patients with advanced solid tumors. The final population pharmacokinetic model was constructed by assessing the effect of covariates on pharmacokinetic parameters including demographic characteristics, laboratory values, hepatic and renal function, and concomitant medications. The robustness of the final model was evaluated using a bootstrap method as well as visual predictive check based on Monte Carlo simulations and goodness-of-fit plots.Results: A total of 559 concentrations from 29 patients were available for pharmacokinetic analysis. A two-compartment linear model with first-order absorption and absorption lag time adequately described the population pharmacokinetics of vactosertib. The estimates of apparent clearance (CL/F) and volume of central compartment (Vc/F) were 31.9 L/h (inter-individual variability, 0.481) and 82.9 L (inter-individual variability, 0.534), respectively. The mixture model accounts for both typical absorption profile in the majority of patients and distinct profile in some patients with uncommon gastrointestinal conditions. Body mass index was significantly associated with Vc/F.Conclusions: The model developed in this study adequately describes the population pharmacokinetics of vactosertib in patients with advanced solid tumors. The pharmacokinetic characteristics assessed using the model would provide useful quantitative information to assist the future clinical development of vactosertib. [ABSTRACT FROM AUTHOR]

The present study aimed to assess the clinical impact of BCR‐ABL1 transcript levels determined at an earlier time point than the 3‐month early molecular response (EMR) in chronic‐phase chronic myeloid leukemia (CML‐CP) patients. BCR‐ABL1 transcript levels of CML‐CP patients (n = 258; median age, 43 [range, 18‐81] years) treated with various tyrosine kinase inhibitors (TKIs) were determined at 4 weeks (28 ± 3 days) and at every 3 months of treatment initiation. At 4 weeks, receiver operating characteristic curves revealed that cutoff values of BCR‐ABL1 transcripts for achieving major molecular responses (MMRs) by 12 and 60 months were 40.89% and 39.16%, respectively (95% CI, 0.658‐0.772 and 95% CI, 0.643‐0.758; P < 0.0001). With 40% of BCR‐ABL1 transcripts at 4 weeks (very early MR; VEMR), patients with VEMR achieved higher 3‐month EMR and 4‐week VEMR significantly associated with higher cumulative incidences of 5‐year MMR (89.1% vs 72.3%; P < 0.001) and 5‐year deep molecular response (DMR) (56.5% vs 29.4%; P = 0.001). Furthermore, event‐free survival (EFS)‐a (93.0% vs 84.8%; P = 0.068) and EFS‐b (71.1% vs 57.9%; P = 0.061) by 5 years were also marginally significant. VEMR and 3‐month EMR were achieved in 89 patients, with significantly superior outcomes. In multivariate analyses, lower leukocyte count (P = 0.008) and frontline second‐generation TKI therapy size (P < 0.001) were significantly associated with VEMR achievement, but not baseline BCR‐ABL1 level and CML duration. In conclusion, the 4‐week BCR‐ABL1 transcript levels including VEMR could be important to predict long‐term outcomes and may provide additional information about innate intrinsic sensitivity to CML among individuals. The very early molecular response assessment could be important to predict long‐term outcomes and may provide additional information about innate intrinsic sensitivity to individual CML clone. As it also allows for the prediction of DMR, VEMR can be used as one of the important tools to select candidates for treatment‐free remission. [ABSTRACT FROM AUTHOR]

Abstract: Radotinib is a second‐generation BCR‐ABL1 tyrosine kinase inhibitor approved for the treatment of chronic myeloid leukemia in chronic phase (CP‐CML). Here, using the data from a Phase 3 study conducted in patients with newly diagnosed CP‐CML, the dose–efficacy as well as dose–safety relationship analyses were performed to determine a safe and effective initial dosage regimen of radotinib. A significant positive association was detected between the starting dose of radotinib adjusted for body weight (Dose/BW) and the probability of dose‐limiting toxicity (≥grade 3 hematologic and nonhematologic toxicity) (P = 0.003). In contrast, a significant inverse association was discovered between Dose/BW and the probability of major molecular response (BCR‐ABL1/ABL1 ≤ 0.1%) when controlled for sex (P = 0.033). Moreover, frequent dose interruptions and reductions secondary to radotinib toxicities occurred in the Phase 3 study, resulting in nearly half (44%) of patients receiving a reduced dose at a 12‐month follow‐up. In conclusion, the results of this study demonstrate the need for initial radotinib dose attenuation to improve the long‐term efficacy and safety of radotinib. Hence, the authors suggest a new upfront radotinib dose of 400 mg once daily be tested in patients with newly diagnosed CP‐CML. [ABSTRACT FROM AUTHOR]

A fixed dose regimen for tyrosine kinase inhibitors (TKIs) is postulated to be responsible for variable safety outcomes in the treatment of chronic myelogenous leukemia (CML). The objective of this study was to explore an optimal dosing regimen for a TKI, radotinib, to improve its safety profile. Clinical data were obtained from a Phase 2 study of fixed-dose radotinib in 77 Asian patients with CML. The magnitude of radotinib dose adjusted for patient’s body weight (Dose/BW) and the probability of dose-limiting toxicity (DLT) demonstrated a positive association (Logit[P] = 0.86*[Dose/BW]-4.45,p = 0.001). There was a significant difference in the Kaplan-Meier curves for time to first DLT between the patient subgroups of Dose/BW <6 and ≥6 mg/kg (259versus83 days). Consequently, a two-tier weight-based dosing regimen may improve the safety of radotinib: 300 mg or 400 mg twice daily for patients weighing ≤65 or >65 kg, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of phosphatidylcholine (PC) on improving the incomplete release of drugs from the bentonite (BT)-drug complex was investigated. • PC and quetiapine (QTP), a model drug were successfully intercalated into BT interlayer space in an amorphous state. • PC improved the release of QTP from the BT complex without disrupting the pH-dependent release property of BT. • The optimum amount of PC significantly enhanced oral bioavailability of poorly water-soluble QTP by facilitating the dissolution. Bentonite (BT) is a biocompatible clay mineral that has advantageous properties as a pharmaceutical excipient. However, the application of BT in controlled-release oral formulations has been challenging due to incomplete drug release from BT-drug complexes. The objective of this study was to investigate the effect of modifying BT with zwitterionic phosphatidylcholine (PC) to enhance the dissolution of drugs, thereby increasing their oral bioavailability. Quetiapine (QTP) was chosen as a model drug, and the composition of the complex (BT-PC-QTP) was optimized to have the maximum QTP content and increase the total amount of QTP released. The in vitro release study showed that the incorporation of an appropriate amount of PC into BT improved the low release rate of the BT-QTP complex at pH 7.4, while the pH-dependent release property of BT was maintained. In an in vivo pharmacokinetic study in rats, the oral administration of the BT-PC-QTP complex showed significantly higher C max and AUC values than the BT-QTP complex. Moreover, BT-PC-QTP showed a 2.4-fold enhancement of oral bioavailability compared to the QTP powder group. The scanning electron microscopy (SEM), powder X-ray diffraction (pXRD), and differential scanning calorimetry (DSC) studies confirmed that the intercalation of PC and QTP into BT resulted in the adsorption of QTP in an amorphous state. The characterization of the nanoparticles generated from the BT-PC-QTP complex supported that PC enhanced the dissolution of QTP by forming nanosized PC particles. Taken together, the modification of BT with PC can be applied in pharmaceutical industry as a platform strategy to control the release of the BT-drug complex and enhance the oral bioavailability of poorly water-soluble drugs. [ABSTRACT FROM AUTHOR]

Bentonite (BT) is a natural clay mainly composed of montmorillonite which has exchangeable cations in the interlayer space. BT has various advantages as a pharmaceutical excipient for the formulation of drug delivery systems (DDSs), including biocompatibility and unique physicochemical properties (i.e. , adsorption and pH-dependent cation exchange). However, previous studies on the application of BT for DDSs were usually limited to the characterization of the in vitro adsorption and release properties. Herein, we prepared and characterized a doxazosin-bentonite (DXBT) composite formulation for controlled oral delivery and then evaluated the pharmacokinetics of doxazosin (DX) in rats. The composition of the DXBT composite was optimized based on the adsorption efficiency and the content of DX in the DXBT composite. The change in morphology was observed by scanning electron microscopy (SEM). Intercalation of amorphous DX between the BT interlayer space was confirmed by powder X-ray diffraction (pXRD). The zeta potential of DXBT composite was higher than BT over the pH range between 1 and 8, and was positive in acidic condition and was changed to negative at pH above 4. The DXBT composite showed pH-dependent in vitro release profiles of DX, and the cumulative release amount at 24 h was higher at pH 7.8 than at pH 1.2 and 7.4 (63.9, 29.3 and 47.8%, respectively). In an in vivo pharmacokinetic study after oral administration in rats, the DXBT composite resulted in a significantly lower peak plasma concentration (C max) and longer terminal half-life (t 1/2) and mean residence time (MRT) of DX compared to DX solution. Thus, the DXBT composite could be an oral drug delivery platform with pH-dependent controlled-release profiles based on the unique ion-exchange property of BT. [Display omitted] • Doxazosin-bentonite composite was investigated for controlled-release oral drug delivery platform. • Doxazosin was intercalated into bentonite by using pH-dependent cationic exchange property. • Surface properties and crystallinity of the doxazosin-bentonite composite were characterized. • Doxazosin-bentonite composite reduced burst release of doxazocin in stomach pH and sustained the release in intestinal pH. • In pharmacokinetic study, doxazosin-bentonite significantly reduced C max and extended half-life. [ABSTRACT FROM AUTHOR]

Purpose: Lobeglitazone, a peroxisome proliferatoractivated receptor-γ agonist, is metabolized primarily by the cytochrome P450 (CYP) 3A4 isoenzyme. Individuals concomitantly taking lobeglitazone and a CYP3A4 inhibitor may experience some adverse effects secondary to increased systemic exposure to lobeglitazone. To address such potential concern, we evaluated the effects of ketoconazole, a prototypic CYP3A4 inhibitor, on the pharmacokinetic (PK) properties and associated adverse effects of lobeglitazone. Methods: A PK drug-drug interaction study was conducted in healthy individuals between 20 and 45 years old in a randomized, open-label, 2-way crossover design. Even though the PK study was performed on a single dose of lobeglitazone, multiple ketoconazole doses were given to ensure that the full extent of inhibition of CYP3A4 was maintained during the PK sampling. All study participants received a single oral dose of lobeglitazone 0.5 mg with or without 9 oral 200-mg doses of ketoconazole pretreatment twice daily. The primary PK parameter end points (AUC and Cmax) were estimated using noncompartmental analysis, and the 90% CIs for the geometric mean ratios (ratio of lobeglitazone and ketoconazole to lobeglitazone alone) were investigated. Tolerability (adverse events, vital signs, ECG, and laboratory tests) was also assessed. Findings: A total of 24 Korean men (mean age, 26 years; age range, 20-32 years; mean weight, 68 kg; weight range, 59-81 kg) completed the study and were evaluable for lobeglitazone PK properties and tolerability. The mean (SD) Cmax values of lobeglitazone with and without ketoconazole were 49 (7) ng/mL and 48 (6) ng/mL at 1.5 and 1.0 hours after dosing, respectively. The mean (SD) AUC∞ values were 532 (117) ng · h/mL and 405 (110) ng · h/mL, respectively. Although the Cmax was not significantly affected, the geometric mean ratio for AUAUC∞ was increased by a point estimate of 1.33 (90% CI, 1.23-1.44). A single oral administration of lobeglitazone 0.5 mg with or without ketoconazole pretreatment did not produce any clinically significant adverse effects on vital signs, 12-lead ECG profiles, or laboratory tests. Implications: The administration of lobeglitazone, 0.5 mg alone or in combination with multiple doses of ketoconazole, was generally well tolerated. The systemic exposure of lobeglitazone was increased to a modest extent by pretreatment with 9 twicedaily doses of ketoconazole. [ABSTRACT FROM AUTHOR]

Abstract: Inactivation of the NF-κB signaling pathway by inhibition of IKKβ is a well-known approach to treat inflammatory diseases such as rheumatoid arthritis and cancer. Thienopyrimidine-based analogues were designed through modification of the known IKKβ inhibitor, SPC-839, and then biologically evaluated. The resulting analogues had good inhibitory activity against both nitric oxide and TNF-α, which are well-known inflammatory responses generated by activated NF-κB. However, no inhibitory activity against IKKβ was observed with these compounds. The thienopyrimidine-based analogues were subsequently screened for a target kinase, and FLT3, which is a potential target for acute myeloid leukemia (AML), was identified. Thienopyrimidine-based FLT3 inhibitors showed good inhibition profiles against FLT3 under 1μM. Overall, these compounds represent a promising family of inhibitors for future development of a treatment for AML. [Copyright &y& Elsevier]

Vactosertib is a novel inhibitor of transforming growth factor-β signaling. Clinical applications of vactosertib have been challenging since conventional oral formulations such as immediate-release tablets demonstrate a rapid rise and fast decline in plasma concentrations. In this study, a novel bentonite-based, modified-release, freeze-dried powder of vactosertib was developed and evaluated to determine its potential in the treatment of ulcerative colitis. The formulation released vactosertib slowly and steadily in an in vitro drug release test. The extent of vactosertib released from the formulation was markedly low (18.0%) at pH 1.2 but considerably high (95.6%) at pH 7.4. Compared with vactosertib oral solution, the formulation demonstrated a 52.5% lower mean maximum concentration of vactosertib and three times longer median time to maximum concentration without a significant change in the extent of vactosertib absorption in a rodent colitis model. Furthermore, colitis mice administered with this formulation showed a significant reduction in the total histopathological score by 30% compared with those administered with the positive control, whereas the administration of vactosertib oral solution resulted in only a 10% reduction. Collectively, this novel formulation resolved the pharmacokinetic drawbacks of vactosertib and is expected to enhance its therapeutic effect by delivering vactosertib to the colitis lesions in the lower gastrointestinal tract. [ABSTRACT FROM AUTHOR]