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Tamoxifen and its metabolite 4-hydroxy-tamoxifen (4OHTam) are two potent molecules that have anticancer properties on breast cancers. Their medical use is expected to increase with the increasing global cancer rate. After consumption, patients excrete tamoxifen and the 4OHTam metabolite into wastewaters, and tamoxifen has been already detected in wastewaters and natural waters. The concentrations of 4OHTam in waters have never been reported. A single study reported 4OHTam effects on the microcrustacean Daphnia pulex. The effects of tamoxifen and 4OHTam over more than two generations are unknown in aquatic invertebrates. The main goal of this study was to assess the long-term sensitivity of the microcrustacean D. pulex over four generations, based on size, reproduction, viability and the intrinsic rate of natural increase (r). Additional experiments were carried out to observe whether the effects of tamoxifen and 4OHTam were reversible in the next generation after descendants were withdrawn from chemical stress (i.e., recovery experiment), and whether the lowest test concentration of each chemical induced toxic effects when both concentrations were combined (i.e., mixture experiments). Our results showed that tamoxifen and 4OHTam induced the adverse effects at environmentally relevant concentrations. Tamoxifen and 4OHTam impaired size, viability, reproduction and the r in four generations of treated D. pulex, but these effects were not clearly magnified over generations. Tamoxifen was more potent than 4OHTam on D. pulex. When used in a mixture, the combination of tamoxifen and 4OHTam induced effects in offspring, whereas no effects were observed when these chemicals were tested individually. In the recovery experiment, the reproduction and size were reduced in offspring withdrawn from chemical exposures. Our results suggested that tamoxifen and its metabolite may be a relevant pharmaceutical to consider in risk assessment., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Low-dose, Visudyne®-mediated photodynamic therapy (photo-induction) was shown to selectively enhance tumor vessel transport causing increased uptake of systemically administered chemotherapy in various tumor types grown on rodent lungs. The present experiments explore the efficacy of photo-induced vessel modulation combined to intravenous (IV) liposomal cisplatin (Lipoplatin®) on rodent lung tumors and the feasibility/toxicity of this approach in porcine chest cavities., Material and Methods: Three groups of Fischer rats underwent orthotopic sarcoma (n = 14), mesothelioma (n = 14), or adenocarcinoma (n = 12) implantation on the left lung. Half of the animals of each group had photo-induction (0.0625 mg/kg Visudyne®, 10 J/cm(2) ) followed by IV administration of Lipoplatin® (5 mg/kg) and the other half received Lipoplatin® without photo-induction. Then, two groups of minipigs underwent intrapleural thoracoscopic (VATS) photo-induction (0.0625 mg/kg Visudyne®; 30 J/cm(2) hilum; 10 J/cm(2) apex/diaphragm) with in situ light dosimetry in combination with IV Lipoplatin® administration (5 mg/kg). Protocol I (n = 6) received Lipoplatin® immediately after light delivery and Protocol II (n = 9) 90 minutes before light delivery. Three additional animals received Lipoplatin® and VATS pleural biopsies but no photo-induction (controls). Lipoplatin® concentrations were analyzed in blood and tissues before and at regular intervals after photo-induction using inductively coupled plasma mass spectrometry., Results: Photo-induction selectively increased Lipoplatin® uptake in all orthotopic tumors. It significantly increased the ratio of tumor to lung Lipoplatin® concentration in sarcoma (P = 0.0008) and adenocarcinoma (P = 0.01) but not in mesothelioma, compared to IV drug application alone. In minipigs, intrapleural photo-induction combined to systemic Lipoplatin® was well tolerated with no toxicity at 7 days for both treatment protocols. The pleural Lipoplatin® concentrations were not significantly different at 10 and 30 J/cm(2) locations but they were significantly higher in protocol I compared to II (2.37 ± 0.7 vs. 1.37 ± 0.7 ng/mg, P  < 0.001)., Conclusion: Visudyne®-mediated photo-induction selectively enhances the uptake of IV administered Lipoplatin® in rodent lung tumors. Intrapleural VATS photo-induction with identical treatment conditions combined to IV Lipoplatin chemotherapy is feasible and well tolerated in a porcine model. Lasers Surg. Med. 47:807-816, 2015. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

Although pharmaceutical metabolites are found in the aquatic environment, their toxicity on living organisms is poorly studied in general. Endoxifen and 4-hydroxy-tamoxifen (4OHTam) are two metabolites of the widely used anticancer drug tamoxifen for the prevention and treatment of breast cancers. Both metabolites have a high pharmacological potency in vertebrates, attributing prodrug characteristics to tamoxifen. Tamoxifen and its metabolites are body-excreted by patients, and the parent compound is found in sewage treatment plan effluents and natural waters. The toxicity of these potent metabolites on non-target aquatic species is unknown, which forces environmental risk assessors to predict their toxicity on aquatic species using knowledge on the parent compounds. Therefore, the aim of this study was to assess the sensitivity of two generations of the freshwater microcrustacean Daphnia pulex towards 4OHTam and endoxifen. Two chronic tests of 4OHTam and endoxifen were run in parallel and several endpoints were assessed. The results show that the metabolites 4OHTam and endoxifen induced reproductive and survival effects. For both metabolites, the sensitivity of D. pulex increased in the second generation. The intrinsic rate of natural increase (r) decreased with increasing 4OHTam and endoxifen concentrations. The No-Observed Effect Concentrations (NOECs) calculated for the reproduction of the second generation exposed to 4OHTam and endoxifen were <1.8 and 4.3 μg/L, respectively, whereas the NOECs that were calculated for the intrinsic rate of natural increase were <1.8 and 0.4 μg/L, respectively. Our study raises questions about prodrug and active metabolites in environmental toxicology assessments of pharmaceuticals. Our findings also emphasize the importance of performing long-term experiments and considering multi-endpoints instead of the standard reproduction outcome., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Satraplatin (JM216; bis-acetatoammine-dichlorocyclohexylamine platinum (IV)) is a platinum (Pt) complex developed in an attempt to circumvent tumour resistance and which can be administered by the oral route. The fate of platinum delivered by this oral formulation administered at various doses under the 5 or 14 days schedule, has been studied to a limited extent., Patients and Methods: Total (Ptot) and ultrafilterable (PtUF) platinum were determined in 19 patients enrolled in phase I (PI) and II (PII) studies (PI, n = 14, advanced cancer; PII, n = 5, untreated small cell lung carcinoma). JM216 doses were 10 to 50 mg m-2 day-1 x 14 d (days) (dose escalation in PI) and 120 mg m-2 day-1 x 5d (fixed dose in PII), administered to fasted patients in a standardized way. Ptot and PtUF levels were determined by atomic absorption spectrometry on d1 and d14, followed over 28 days in PI; and on d1, followed over 5 days in PII. Pharmacokinetic parameters were derived by a noncompartmental approach., Results: JM216 is rapidly absorbed with a Tmax obtained within 2.5-3 hours and 1-2 hours for Ptot and PtUF, respectively. The pharmacokinetics of JM216 was linear across the tested doses in PI, with the exposure of Ptot on d14 being better correlated with dose per BSA (Body surface area) (r = 0.91) than that of PtUF (r = 0.61). In PI, Cmax on d1 increased proportionally to the dose (r = 0.82 and r = 0.72 for Ptot and PtUF, respectively). Apparent clearances in PI were 1.1 +/- 0.5 L h-1 and 37.0 +/- 33 L h-1 for Ptot and PtUF, respectively. Prolonged terminal half-lives were observed after the last JM216 administration with mean values of 216 +/- 37 hours and 107 +/- 89 hours, for Ptot and PtUF respectively. The accumulation ratio (Cmaxd14/Cmaxd1) indicated a higher accumulation of Ptot (3.5 +/- 1.6) than of PtUF (1.8 +/- 1) under multiple dose regimen. The apparent volumes of distribution (terminal phase) were similar in the PI and PII studies: 326 +/- 112 L and 3094 +/- 1493 L, and 557 +/- 267 L and 4154 +/- 2147 L, for Ptot and PtUF, respectively. In PI, the nadir of thrombocytopenia was related both to the cumulated dose of JM216 (r = 0.81) and to the AUC of Ptot on d14 (r = 0.77), whereas the AUC of PtUF was not predictive (r = 0.48). The Cmax of Ptot and PtUF on d1 was related to neutropenia (r = 0.61 and r = 0.65, respectively) and to thrombocytopenia (r = 0.77 and r = 0.74, respectively). No relationships were found between leukocytes or neutrophils percent decrease and the AUCs or total, dose of JM216., Conclusion: JM216 is an orally bioavailable platinum-containing chemotherapeutic agent yielding predictable total levels of platinum which appears to accumulate in plasma after multiple administration over 14 days. These results should be set in relation to clinical efficacy and tolerance, to optimise the dose regimen of JM216 in further studies.

Simple Summary: Poor adherence to trametinib, an oral anticancer drug, may be the consequence of side effects that severely impact the patient's quality of life. The significant interindividual variability associated with poor adherence results in suboptimal drug exposure and consequently in unfavourable patient outcomes. By characterizing the pharmacokinetics of trametinib, this study aims to assess (i) the adequacy of recommended doses to achieve efficacy thresholds and (ii) the impact of non-adherence on drug exposure. The latter was assessed by simulating different scenarios of missing one or more doses per week to highlight the risk of treatment failure associated with poor adherence. These results promote interprofessional collaboration and patient partnership to address patients' needs in order to ensure adherence to trametinib and in fine therapeutic success. Trametinib is a targeted therapy used for the treatment of solid tumours, with significant variability reported in real-life studies. This variability increases the risk of suboptimal exposure, which can lead to treatment failure or increased toxicity. Using model-based simulation, this study aims to characterize and investigate the pharmacokinetics and the adequacy of the currently recommended doses of trametinib. Additionally, the simulation of various suboptimal adherence scenarios allowed for an assessment of the impact of patients' drug adherence on the treatment outcome. The population data collected in 33 adult patients, providing 113 plasmatic trametinib concentrations, were best described by a two-compartment model with linear absorption and elimination. The study also identified a significant positive effect of fat-free mass and a negative effect of age on clearance, explaining 66% and 21% of the initial associated variability, respectively. Simulations showed that a maximum dose of 2 mg daily achieved the therapeutic target in 36% of male patients compared to 72% of female patients. A dose of 1.5 mg per day in patients over 65 years of age achieved similar rates, with 44% and 79% for male and female patients, respectively, reaching the therapeutic target. Poor adherence leads to a significant drop in concentrations and a high risk of subtherapeutic drug levels. These results underline the importance of interprofessional collaboration and patient partnership along the patient's journey to address patients' needs regarding trametinib and support medication adherence. [ABSTRACT FROM AUTHOR]