Exploring the contribution of genetic variants to high sunitinib exposure in patients with cancer.

Aims: Sunitinib exhibits considerable interindividual variability in exposure. While the target total plasma concentration of sunitinib and its active metabolite is 50-87.5 ng/mL for the intermittent dosing schedule, ~10-21% of patients experience higher exposures (>87.

Exposure-response analyses of cabozantinib in patients with metastatic renal cell cancer.

Aim: In the registration trial, cabozantinib exposure ≥ 750 ng/mL correlated to improved tumor size reduction, response rate and progression free survival (PFS) in patients with metastatic renal cell cancer (mRCC). Because patients in routine care often differ from patients in clinical trials, we explored the cabozantinib exposure-response relationship in patients with mRCC treated in routine care.

Methods: Cabozantinib trough concentrations (C) were collected and average exposure was calculated per individual.

Excessive toxicity of cabozantinib in a phase II study in patients with recurrent and/or metastatic salivary gland cancer.

Aim: Because the tyrosine kinases c-MET and vascular endothelial growth factor receptors (VEGFR) are often overexpressed in salivary gland cancer (SGC), this study evaluated the efficacy and safety of cabozantinib in patients with recurrent/metastatic (R/M) SGC.

Patients And Methods: A single-centre phase II study was conducted. Patients with immunohistochemical c-MET-positive R/M SGC were included in three cohorts: adenoid cystic carcinoma (ACC); salivary duct carcinoma (SDC) and other miscellaneous SGCs.

Lost in third space: altered tyrosine-kinase inhibitor pharmacokinetics in a patient with malignant ascites.

Background: Pazopanib and sunitinib are oral tyrosine kinase inhibitors (TKI) approved for the treatment of renal cell carcinoma. For both oncolytics, a clear target trough concentration level in plasma has been defined above which improved clinical efficacy can be expected. However, many factors can alter TKI exposure, including disease characteristics.

Exposure-toxicity relationship of cabozantinib in patients with renal cell cancer and salivary gland cancer.

Cabozantinib is registered in fixed 60 mg dose. However, 46% to 62% of patients in the registration studies needed a dose reduction due to toxicity. Improved clinical efficacy has been observed in renal cell carcinoma patients (RCC) with a cabozantinib exposure greater than 750 μg/L.

The impact of a 1-hour time interval between pazopanib and subsequent intake of gastric acid suppressants on pazopanib exposure.

Co-treatment with gastric acid suppressants (GAS) in patients taking anticancer drugs that exhibit pH-dependant absorption may lead to decreased drug exposure and may hamper drug efficacy. In our study, we investigated whether a 1-hour time interval between subsequent intake of pazopanib and GAS could mitigate this negative effect on drug exposure. We performed an observational study in which we collected the first steady-state pazopanib trough concentration (C ) levels from patients treated with pazopanib 800 mg once daily (OD) taken fasted or pazopanib 600 mg OD taken with food.

The relationship between sunitinib exposure and both efficacy and toxicity in real-world patients with renal cell carcinoma and gastrointestinal stromal tumour.

Aim: Sunitinib is an oral tyrosine kinase inhibitor approved for the treatment of renal cell carcinoma (RCC) and gastrointestinal stromal tumor (GIST). Because of the large interpatient pharmacokinetic variability and established exposure-response and exposure-toxicity relationships in clinical trial patients, therapeutic drug monitoring (TDM) seems promising for optimizing sunitinib exposure. We aimed to investigate the relationship between sunitinib exposure and treatment outcome in a real-world patient cohort.

Quantification of cobimetinib, cabozantinib, dabrafenib, niraparib, olaparib, vemurafenib, regorafenib and its metabolite regorafenib M2 in human plasma by UPLC-MS/MS.

A sensitive and selective ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous determination of seven oral oncolytics (two PARP inhibitors, i.e. olaparib and niraparib, and five tyrosine kinase inhibitors, i.

Unexpected Serotonin Syndrome, Epileptic Seizures, and Cerebral Edema Following 2,5-dimethoxy-4-bromophenethylamine Ingestion.

4-bromo-2,5-dimethoxyphenethylamine (2C-B) is a designer drug. In Europe, 2C-B is easily obtained and used for recreational purposes. It is known for its stimulating effects similar to those of 3,4-methylenedioxymethamphetamine, although in higher doses it has more hallucinogenic effects.

Population Pharmacokinetics of Ganciclovir in Critically Ill Patients.

Background: The pharmacokinetic (PK) data of ganciclovir (GCV), a first-line antiviral treatment for cytomegalovirus infections, in critically ill patients are limited. This study aimed at characterizing GCV population PK and interindividual variability (IIV) in intensive care unit (ICU) patients. Secondary objectives were to identify patient characteristics responsible for IIV and simulate GCV exposure for different dosing regimens.

Dose recommendations for anticancer drugs in patients with renal or hepatic impairment.

Renal or hepatic impairment is a common comorbidity for patients with cancer either because of the disease itself, toxicity of previous anticancer treatments, or because of other factors affecting organ function, such as increased age. Because renal and hepatic function are among the main determinants of drug exposure, the pharmacokinetic profile might be altered for patients with cancer who have renal or hepatic impairment, necessitating dose adjustments. Most anticancer drugs are dosed near their maximum tolerated dose and are characterised by a narrow therapeutic index.

Pharmacogenetic Discovery in CALGB (Alliance) 90401 and Mechanistic Validation of a VAC14 Polymorphism that Increases Risk of Docetaxel-Induced Neuropathy.

Purpose: Discovery of SNPs that predict a patient's risk of docetaxel-induced neuropathy would enable treatment individualization to maximize efficacy and avoid unnecessary toxicity. The objectives of this analysis were to discover SNPs associated with docetaxel-induced neuropathy and mechanistically validate these associations in preclinical models of drug-induced neuropathy.

Experimental Design: A genome-wide association study was conducted in metastatic castrate-resistant prostate cancer patients treated with docetaxel, prednisone and randomized to bevacizumab or placebo on CALGB 90401.

Poor performance of laboratories assaying newly developed antiretroviral agents: results for darunavir, etravirine, and raltegravir from the international quality control program for therapeutic drug monitoring of antiretroviral drugs in human plasma/serum.

Background: The International Interlaboratory Quality Control PROGRAM for Therapeutic Drug Monitoring of Antiretroviral Drugs in Human Plasma/Serum was initiated in 1999. We have previously published our experience during the first 10 years of the PROGRAM. Since 2010, 3 newly developed antiretroviral agents have been added to the

Program: darunavir, etravirine, and raltegravir.

Pharmacogenetics, enzyme probes and therapeutic drug monitoring as potential tools for individualizing taxane therapy.

The taxanes are a class of chemotherapeutic agents that are widely used in the treatment of various solid tumors. Although taxanes are highly effective in cancer treatment, their use is associated with serious complications attributable to large interindividual variability in pharmacokinetics and a narrow therapeutic window. Unpredictable toxicity occurrence necessitates close patient monitoring while on therapy and adverse effects frequently require decreasing, delaying or even discontinuing taxane treatment.