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Everolimus is a mammalian target of rapamycin inhibitor approved for the treatment of various tumor types. Less invasive measurement of everolimus concentrations could facilitate pharmacokinetic studies and personalized dosing based on whole blood concentrations, known as therapeutic drug monitoring. Volumetric Absorptive Microsampling (VAMS) has been introduced as a patient friendly, less invasive sampling technique to obtain an accurate volume of whole blood regardless of hematocrit value. We describe the bioanalytical validation and clinical application of a liquid chromatography tandem mass spectrometry (LC-MS/MS) method to quantify everolimus using VAMS. For the quantification, 13C2D4-Everolimus was used as internal standard (IS). Everolimus and the IS were extracted with methanol from the VAMS device, which was evaporated after ultrasonification and shaking. The residue was reconstituted in 20 mM ammonium formate buffer and methanol (50%, v/v) of which 5 μL was injected into the LC-MS/MS system. Quantification was performed for the ammonium adduct of everolimus in positive electrospray ion mode. The VAMS method met all pre-defined validation criteria. Accuracy and precision were within 11.1% and ≤14.6%, respectively. Samples were shown to be stable on the VAMS device for at least 362 days at ambient temperatures. Considerable biases from −20 to 31% were observed over a 30–50% hematocrit range. Although the method fulfilled all validation criteria, the perceived advantage of VAMS over dried blood spot sampling could not be demonstrated. Despite the effect of hematocrit, using an empirically derived formula the whole blood everolimus concentration could be back calculated with reasonable accuracy in the clinical application study.

Pazopanib is an angiogenesis inhibitor approved for the treatment of renal cell carcinoma and soft tissue sarcoma. Post hoc analysis of a clinical trial demonstrated a relationship between pazopanib trough concentrations (CRenal cell cancer and soft tissue sarcoma patients who had at least one pazopanib plasma concentration available were included. Using calculated CSixty-one patients were included, of which 16.4% were underexposed (mean CThis study confirms that pazopanib C

BACKGROUND: Abiraterone acetate and enzalutamide are 2 novel drugs for the treatment of metastatic castration-resistant prostate cancer. The metabolism of these drugs is extensive. Major metabolites are N-desmethyl enzalutamide, enzalutamide carboxylic acid, abiraterone N-oxide sulfate, and abiraterone sulfate; of which N-desmethyl enzalutamide is reported to possess antiandrogen capacities. A liquid chromatography-tandem mass spectrometry method for simultaneous quantification of abiraterone, enzalutamide, and the main metabolites has been developed and validated to support therapeutic drug monitoring. METHODS: Human plasma samples of patients treated with abiraterone or enzalutamide were harvested at the clinic and stored at -20°C. Proteins were precipitated by acetonitrile, and the final extract was injected on a Kinetex C18 column and separated with gradient elution. Analytes were detected by liquid chromatography-mass spectrometry (Triple Quad 6500). RESULTS: The method was validated over various linear ranges: 1-100 ng/mL for abiraterone, 5-500 ng/mL for enzalutamide and enzalutamide carboxylic acid, 10-1000 ng/mL for N-desmethyl enzalutamide, 30-3000 ng/mL for abiraterone N-oxide sulfate, and 100-10,000 ng/mL for abiraterone sulfate. Intra-assay and interassay variabilities were within ±15% of the nominal concentrations for quality control samples at medium and high concentrations and within ±20% at the lower limit of quantification, respectively. CONCLUSIONS: The described method for simultaneous determination of abiraterone and enzalutamide was validated successfully and provides a useful tool for therapeutic drug monitoring in patients treated with these agents.

SummaryNiraparib is an investigational oral, once daily, selective poly(ADP-Ribose) polymerase (PARP)-1 and PARP-2 inhibitor. In the pivotal Phase 3 NOVA/ENGOT/OV16 study, niraparib met its primary endpoint of improving progression-free survival (PFS) for adult patients with recurrent, platinum sensitive, ovarian, fallopian tube, or primary peritoneal cancer in complete or partial response to platinum-based chemotherapy. Significant improvements in PFS were seen in all patient cohorts regardless of biomarker status. This study evaluates the absorption, metabolism and excretion (AME) of 14C–niraparib, administered to six patients as a single oral dose of 300 mg with a radioactivity of 100 μCi. Total radioactivity (TRA) in whole blood, plasma, urine and faeces was measured using liquid scintillation counting (LSC) to obtain the mass balance of niraparib. Moreover, metabolite profiling was performed on selected plasma, urine and faeces samples using liquid chromatography – tandem mass spectrometry (LC-MS/MS) coupled to off-line LSC. Mean TRA recovered over 504 h was 47.5% in urine and 38.8% in faeces, indicating that both renal and hepatic pathways are comparably involved in excretion of niraparib and its metabolites. The elimination of 14C–radioactivity was slow, with t1/2 in plasma on average 92.5 h. Oral absorption of 14C–niraparib was rapid, with niraparib concentrations peaking at 2.49 h, and reaching a mean maximum concentration of 540 ng/mL. Two major metabolites were found: the known metabolite M1 (amide hydrolysed niraparib) and the glucuronide of M1. Based on this study it was shown that niraparib undergoes hydrolytic, and conjugative metabolic conversions, with the oxidative pathway being minimal.

Miltefosine is an oral agent against the neglected tropical disease leishmaniasis, which is mostly endemic in resource-poor areas. Dried blood spot (DBS) sampling is an attractive alternative to plasma sampling for pharmacokinetic studies in these remote areas, but introduces additional variability in analyte quantification due to possible blood spot inhomogeneity and variability in blood spot volume and haematocrit values. Volumetric absorptive microsampling (VAMS) potentially overcomes a few of these issues as the VAMS device absorbs a fixed volume that is processed as a whole. We developed and validated an LC-MS/MS method for the quantification of miltefosine with this novel sampling technique with good performance in terms of linearity, selectivity, accuracy (bias within ±10.8%), precision (CV%≤11.9%), recovery, carry-over and matrix effect. VAMS samples were stable for at least one month at room temperature and 37°C. The impact of haematocrit on assay accuracy was reduced compared to conventional DBS sampling, but indicated a declining recovery with increased haematocrit due to haematocrit dependency in recovery from the sampling device. A clinical validation will be required to investigate whether VAMS is an appropriate and cost-effective alternative sampling method to conventional DBS sampling.

BackgroundPoly (ADP-ribose) Polymerase (PARP) inhibitors are promising novel radiosensitisers. Pre-clinical models have demonstrated potent and tumour-specific radiosensitisation by PARP inhibitors. Olaparib is a PARP inhibitor with a favourable safety profile in comparison to clinically used radiosensitisers including cisplatin when used as single agent. However, data on safety, tolerability and efficacy of olaparib in combination with radiotherapy are limited.MethodsOlaparib is dose escalated in combination with radical (chemo-)radiotherapy regimens for non-small cell lung cancer (NSCLC), breast cancer and head and neck squamous cell carcinoma (HNSCC) in three parallel single institution phase 1 trials. All trials investigate a combination treatment of olaparib and radiotherapy, the NSCLC trial also investigates a triple combination of olaparib, radiotherapy and concurrent low dose cisplatin. The primary objective is to identify the maximum tolerated dose of olaparib in these combination treatments, defined as the dose closest to but not exceeding a 15% probability of dose limiting toxicity. Each trial has a separate dose limiting toxicity definition, taking into account incidence, duration and severity of expected toxicities without olaparib. Dose escalation is performed using a time-to-event continual reassessment method (TITE-CRM). TITE-CRM enables the incorporation of late onset toxicity until one year after treatment in the dose limiting toxicity definition while maintaining an acceptable trial duration. Olaparib treatment starts two days before radiotherapy and continues during weekends until two days after radiotherapy. Olaparib will also be given two weeks and one week before radiotherapy in the breast cancer trial and HNSCC trial respectively to allow for translational research. Toxicity is scored using common terminology criteria for adverse events (CTCAE) version 4.03. Blood samples, and tumour biopsies in the breast cancer trial, are collected for pharmacokinetic and pharmacodynamic analyses.DiscussionWe designed three parallel phase 1 trials to assess the safety and tolerability of the PARP inhibitor olaparib in combination with radical (chemo-)radiotherapy treatment regimens. PARP inhibitors have the potential to improve outcomes in patients treated with radical (chemo-)radiotherapy, by achieving higher locoregional control rates and/or less treatment associated toxicity.Trial registrationClinicalTrials.govIdentifiers: NCT01562210 (registered March 23, 2012), NCT02227082 (retrospectively registered August 27, 2014), NCT02229656 (registered September 1, 2014).

Background Cancer immunotherapy has changed the standard of care for a subgroup of patients with advanced disease. Immune checkpoint blockade (ICB) in particular has shown improved survival compared with previous standards of care for several tumor types. Although proven to be successful in more immunogenic tumors, ICB is still largely ineffective in patients with tumors that are not infiltrated by immune cells, the so-called cold tumors. Patients and methods This review describes the effects of different chemotherapeutic agents on the immune system and the potential value of these different types of chemotherapy as combination partners with ICB in patients with solid tumors. Both preclinical data and currently ongoing clinical trials were evaluated. In addition, we reviewed findings regarding different dosing schedules, including the effects of an induction phase and applying metronomic doses of chemotherapy. Results Combining ICB with other treatment modalities may lead to improved immunological conditions in the tumor microenvironment and could thereby enhance the antitumor immune response, even in tumor types that are so far unresponsive to ICB monotherapy. Chemotherapy, that was originally thought to be solely immunosuppressive, can exert immunomodulatory effects which may be beneficial in combination with immunotherapy. Each chemotherapeutic drug impacts the tumor microenvironment differently, and in order to determine the most suitable combination partners for ICB it is crucial to understand these mechanisms. Conclusion Preclinical studies demonstrate that the majority of chemotherapeutic drugs has been shown to exert immunostimulatory effects, either by inhibiting immunosuppressive cells and/or activating effector cells, or by increasing immunogenicity and increasing T-cell infiltration. However, for certain chemotherapeutic agents timing, dose and sequence of administration of chemotherapeutic agents and ICB is important. Further studies should focus on determining the optimal drug combinations, sequence effects and optimal concentration–time profiles in representative preclinical models.

Vosaroxin is a first-in-class anticancer quinolone derivative topoisomerase II inhibitor that is currently in development in combination with cytarabine for the treatment of acute myeloid leukemia (AML). To investigate vosaroxin pharmacokinetics (PK) in patients, liquid chromatography tandem mass spectrometry (LC-MS/MS) assays to quantify vosaroxin and the two metabolites N-desmethylvosaroxin and O-desmethylvosaroxin in human plasma and urine were developed and validated. Immediately after collection the samples were stored at -80°C. Prior to analysis, the plasma samples were subjected to protein precipitation and the urine samples were diluted. For both assays the reconstituted extracts were injected on a Symmetry Shield RP8 column and gradient elution was applied using 0.1% formic acid in water and acetonitrile-methanol (50:50, v/v). Analyses were performed with a triple quadruple mass spectrometer in positive-ion mode. A deuterated isotope of vosaroxin was used as internal standard for the quantification. The validated assays quantify vosaroxin and N-desmethylvosaroxin in the concentration range of 2-500ng/mL in plasma and urine. For O-desmethylvosaroxin the concentration range of 4-500ng/mL in plasma and urine was validated. Dilution integrity experiments show that samples can be diluted 25 fold in control matrix prior to analysis. The expanded concentration range for plasma and urine for vosaroxin and N-desmethylvosaroxin is therefore from 2 to 15,000ng/mL and in plasma for O-desmethylvosaroxin from 4 to 15,000ng/mL.

Ibrutinib is a targeted covalent inhibitor frequently used for the treatment of various lymphomas. In addition to oxidative metabolism, it is metabolized through glutathione coupling. The quantitative insight into this kind of metabolism is scarce, and tools for quantitation are lacking. The non-oxidative metabolism could prove a more prominent role when oxidative metabolism is impaired. Also, in-vitro studies could over-estimate the effect of CYP450-inhibition. To gain quantitative insight into this relatively unknown biotransformation pathway of the drug we have developed a validated simple, fast and sensitive bio-analytical assay for ibrutinib, dihydrodiol-ibrutinib, and the glutathione, cysteinylglycine and cysteine conjugates of ibrutinib in human plasma. The method emphasizes on simplicity, the thiol-conjugates were synthesized by a simple one step synthesis, followed by LC-purification. Sample preparation was done by a simple protein crash with acetonitrile containing labeled internal standards, evaporation of solvents, and reconstitution in eluent. Finally, the compounds were quantified using UHPLC-MS/MS. The assay was successfully validated in a 0.5-500nM calibration range for all compounds, and also a lower range of 0.05-50 nM was demonstrated for ibrutinib to accommodate for even the lowest trough levels. This assay has a considerably higher sensitivity than previous published assays, with the previous lowest LLOQ being 1.14 nM. Both, ibrutinib, dihydrodiol-ibrutinib and the cysteine conjugate were deemed stable under refrigerated or frozen storage conditions. At room temperature, the glutathione conjugate showed rapid degradation into the cysteinylglycine conjugate in plasma. Finally, the applicability of the assay was demonstrated in patient samples.

Omacetaxine mepesuccinate (hereafter called omacetaxine) is a modified cephalotaxine and is registered (Synribo®) for the treatment of adult patients with chronic myeloid leukemia (CML) with resistance and/or intolerance to two or more tyrosine kinase inhibitors (TKIs). To evaluate the pharmacokinetics of omacetaxine, sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays for the quantification of omacetaxine and its inactive 4'-des-methyl (4'-DMHHT) and cephalotaxine metabolites in human plasma and urine were developed and validated.Since omacetaxine is mainly metabolised by esterases, the plasma samples were immediately stabilised after collection with an esterase inhibitor and stored at a nominal temperature of -80. °C. Urine samples were stored at -80. °C immediately after collection. Protein precipitation was applied as the sample pretreatment method for the plasma samples, and urine samples were processed using solid-phase extraction (SPE). For both assays, the dried and reconstituted extracts were injected on a XBridge BEH Phenyl column for analysis of all analytes. Gradient elution was applied with 0.1% formic acid in water and methanol as mobile phases. Analytes were ionised using a turbospray ionisation source in positive mode and detected with a triple quadrupole mass spectrometer.The validated plasma assay quantifies all analytes in the concentration range of 0.1-100. ng/mL and the urine assay in the range of 0.1-50. ng/mL. At all concentrations, the accuracies were within ±15% of the nominal concentrations and precisions were ≤15%. The developed methods have successfully been applied in a human mass balance study of omacetaxine.

Objectives The primary objective of this study was to identify the total intramural cost of illness of metastatic non-small cell lung cancer (NSCLC) in the Netherlands between 2006–2012. Secondary objective was to identify whether changes in cost patterns of metastatic NSCLC have occurred over the last years. Methods Patients diagnosed with metastatic NSCLC between 1-1-2006 and 31-12-2012, who had follow-up to death or the date of data cut-off and no trial participation were included. A structured chart review was performed using a case report form. Data collection started after diagnosis of metastatic NSCLC and ended at death or April first, 2015. Data regarding outpatient visits, clinical attendance, oncolytic drug use, imaging, lab tests, radiotherapy and surgery were collected. Results Sixty-seven patients were included with a median age of 67 years. The median follow-up was 234 days. On average patients had 28 outpatient visits and 11 inpatient days. Oncolytic drugs were administered to 76% of the patients. Mean per patient expenditures amounted up to €17,463, with oncolytic drugs (€6,390) as the main cost driver. In comparison with the time-period of 2003–2005 total per patient per year expenses decreased by 44%. The contribution to total yearly costs of oncolytic drugs increased from 18% to 35%, while costs for inpatient stay decreased from 52% to 28% of total expenditures. Conclusion Outcomes in this study demonstrate that average treatment costs for metastatic NSCLC in the Netherlands Cancer Institute amount to €17,463. Compared to a prior study the average cost for metastatic NSCLC over time in the Netherlands has decreased. A shift of main cost drivers seems to have occurred from inpatient stay, to oncolytic drugs as main contributor. The shift towards treatment cost might become more visible with the introduction of immunotherapy. These results mark the importance of up-to-date cost of illness studies.

Dexamphetamine is registered for the treatment of attention deficit hyperactivity disorder and narcolepsy. Current research has highlighted the possible application of dexamphetamine in the treatment of cocaine addiction. To support clinical pharmacologic trials a new simple, fast, and sensitive assay for the quantification of dexamphetamine in human plasma using liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed. Additionally, it is the first reported LC-MS assay with these advantages to be fully validated according to current US FDA and EMA guidelines. Human plasma samples were collected on an outpatient basis and stored at nominally -20°C. The analyte and the internal standard (stable isotopically labeled dexamphetamine) were extracted using double liquid-liquid extraction (plasma-organic and organic-water) combined with snap-freezing. The aqueous extract was filtered and 2μL was injected on a C18-column with isocratic elution and analyzed with triple quadrupole mass spectrometry in positive ion mode. The validated concentration range was from 2.5-250ng/mL and the calibration model was linear. A weighting factor of 1 over the squared concentration was applied and correlation coefficients of 0.997 or better were obtained. At all concentrations the bias was within ±15% of the nominal concentrations and imprecision was ≤15%. All results were within the acceptance criteria of the latest US FDA guidance and EMA guidelines on method validation. In conclusion, the developed method to quantify dexamphetamine in human plasma was fit to support a clinical study with slow-release dexamphetamine.

BACKGROUND:: Z-endoxifen (further referred to as endoxifen, unless stated otherwise) is proposed as the most important metabolite of tamoxifen. Patients receiving adjuvant tamoxifen treatment with endoxifen levels below the threshold of 5.9 ng/mL may have an increased risk of breast cancer recurrence. Several factors, such as genetic polymorphisms, drug interactions, and (non-)adherence, lead to large inter-patient variability in endoxifen exposure, resulting in a substantial number of patients showing sub therapeutic levels. As genotyping and phenotyping are not able to adequately predict endoxifen exposure, therapeutic drug monitoring (TDM) seems to be the best approach for tailored tamoxifen therapy. METHODS:: To support TDM services, a rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for the quantification of endoxifen in human serum was developed and validated. Validation was performed according to the latest US FDA and EMA guidelines on bioanalytical method validation. RESULTS:: The successfully validated serum assay quantifies endoxifen with a linear regression calibration model (weighted 1/x) in the concentration range from 1.00 to 25.0 ng/mL. The assay was validated with an inaccuracy of ±7.7% and an imprecision of ≤3.9%, obtained with an IS normalized matrix factor of 0.925 and a signal-to-noise ratio of >66. CONCLUSION:: All validation parameters fulfilled their acceptance criteria and the developed assay is now successfully being used to support TDM services. Thus far, 33.3% of the more than 500 determined endoxifen serum levels were below the threshold of 5.9 ng/mL.

BACKGROUND: The intestinal uptake of the taxanes paclitaxel and docetaxel is seriously hampered by drug efflux through P-glycoprotein (P-gp) and drug metabolism via cytochrome P450 (CYP) 3A. The resulting low oral bioavailability can be boosted by co-administration of P-gp or CYP3A4 inhibitors. METHODS: Paclitaxel or docetaxel (10 mg/kg) was administered to CYP3A4-humanised mice after administration of the P-gp inhibitor elacridar (25 mg kg(-1)) and the CYP3A inhibitor ritonavir (12.5 mg kg(-1)). Plasma and brain concentrations of the taxanes were measured. RESULTS: Oral co-administration of the taxanes with elacridar increased plasma concentrations of paclitaxel (10.7-fold, P

The small molecular Kinase Inhibitor (smKI) drug class is very promising and rapidly expanding. All of these drugs are administered orally. The clear relationship between structure and function has led to drugs with a general low intrinsic solubility. The majority of the commercial pharmaceutical formulations of the smKIs are physical mixtures that are limited by the low drug solubility of a salt form. This class of drugs is therefore characterized by an impaired and variable bioavailability rendering them costly and their therapies suboptimal. New formulations are sparingly being reported in literature and patents. The presented data suggests that continued research into formulation design can help to develop more efficient and cost-effective smKI formulation. Moreover, it may also be of help in the future design of the formulations of new smKIs.

Niraparib (MK-4827) is a novel poly(ADP-Ribose) polymerase (PARP) inhibitor currently investigated in phase III clinical trials to treat cancers. The development of a new drug includes the characterisation of absorption, metabolism and excretion (AME) of the compound. AME studies are a requirement of regulatory agencies and for this purpose bioanalytical assays are essential. This article describes the development and validation of a bioanalytical assay for niraparib and its carboxylic acid metabolite M1 in human plasma and urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sample pre-treatment involved protein precipitation for plasma and dilution of urine samples using acetonitrile-methanol (50:50, v/v). Final extracts were injected onto a SunFire C18 column and gradient elution using 20mM ammonium acetate (mobile phase A) and formic acid:acetonitrile:methanol (0.1:50:50, v/v/v) (mobile phase B) was applied. Detection was performed on an API5500 tandem mass spectrometer operating in the positive electrospray ionisation mode applying multiple reaction monitoring (MRM). The assay was successfully validated in accordance with the Food and Drug Administration and latest European Medicines Agency guidelines on bioanalytical method validation and can therefore be applied in pharmacological clinical studies.

Dabrafenib (Tafinlar(®)) and trametinib (Mekinist(®)) are registered for the treatment of patients with BRAF V600 mutation positive unresectable or metastatic melanoma. To support therapeutic drug monitoring (TDM) and clinical pharmacological trials, an assay to simultaneously quantify dabrafenib and trametinib in human plasma using liquid chromatography tandem mass spectrometry was developed and validated. Human plasma samples were collected on an outpatient base and stored at nominally -20°C. Analytes and internal standards (stable isotope labeled compounds) were extracted with TBME. After snap freezing the samples in a dry ice-ethanol bath, the organic layer was transferred to a clean tube and evaporated under a gentle stream of nitrogen gas. The dry extract was then reconstituted with 100μL acetonitrile and 5μL of the final extract was injected and separated on a C18 column with gradient elution, and analyzed with triple quadrupole mass spectrometry in positive-ion mode. The validated assay ranges from 50 to 5000ng/mL for dabrafenib and 0.5-50ng/mL for trametinib were linear, and correlation coefficient (r(2)) of 0.996 or better. At all concentrations of both analytes the biases were within ±15% of the nominal concentrations and precisions were ≤15%. All results were within the acceptance criteria of the latest US FDA guidance and EMA guidelines on method validation. Dabrafenib was found to degrade under the influence of light in different organic solvents and at least seven degradation products were detected. In conclusion, the described method to simultaneously quantify dabrafenib and trametinib in human plasma was successfully validated and applied for therapeutic drug monitoring in cancer patients treated with dabrafenib and trametinib.

Lurbinectedin is a novel highly selective inhibitor of RNA polymerase II triggering caspase-dependent apoptosis of cancerous cells. This article describes the development and validation of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay to quantify lurbinectedin in human plasma and urine. Plasma samples were pre-treated with 1 M aqueous ammonia after which they were brought onto supported liquid extraction (SLE) columns. Lurbinectedin was eluted from the columns using tert-butyl methyl ether (TBME). Urine was first diluted in plasma and lurbinectedin was extracted from this matrix by liquid-liquid extraction using TBME. Samples were measured by LC-MS/MS in the positive electron ion spray mode. The method was linear over 0.1-100 ng/mL and 1-1000 ng/mL in plasma and urine, respectively, with accuracies and precisions within ±15% (20% for LLOQ) and below 15% (20% for LLOQ), respectively. The method was developed to support a mass balance study in which patients received a dose of 5 mg lurbinectedin.

Purpose: Paclitaxel and carboplatin are frequently used in advanced ovarian cancer following cytoreductive surgery. Threshold models have been used to predict paclitaxel pharmacokinetic-pharmacodynamics, whereas the time above paclitaxel plasma concentration of 0.05 to 0.2 μmol/L (tC > 0.05−0.2) predicts neutropenia. The objective of this study was to build a population pharmacokinetic-pharmacodynamic model of paclitaxel/carboplatin in ovarian cancer patients. Experimental Design: One hundred thirty-nine ovarian cancer patients received paclitaxel (175 mg/m2) over 3 h followed by carboplatin area under the concentration-time curve 5 mg/mL*min over 30 min. Plasma concentration-time data were measured, and data were processed using nonlinear mixed-effect modeling. Semiphysiologic models with linear or sigmoidal maximum response and threshold models were adapted to the data. Results: One hundred five patients had complete pharmacokinetic and toxicity data. In 34 patients with measurable disease, objective response rate was 76%. Neutrophil and thrombocyte counts were adequately described by an inhibitory linear response model. Paclitaxel tC > 0.05 was significantly higher in patients with a complete (91.8 h) or partial (76.3 h) response compared with patients with progressive disease (31.5 h; P = 0.02 and 0.05, respectively). Patients with paclitaxel tC > 0.05 > 61.4 h (mean value) had a longer time to disease progression compared with patients with paclitaxel tC > 0.05 < 61.4 h (89.0 versus 61.9 weeks; P = 0.05). Paclitaxel tC > 0.05 was a good predictor for severe neutropenia (P = 0.01), whereas carboplatin exposure (Cmax and area under the concentration-time curve) was the best predictor for thrombocytopenia (P < 10−4). Conclusions: In this group of patients, paclitaxel tC > 0.05 is a good predictive marker for severe neutropenia and clinical outcome, whereas carboplatin exposure is a good predictive marker for thrombocytopenia.

Background: This phase I study evaluated the safety, tolerability, maximum tolerated dose (MTD) and pharmacokinetics of two dosing schedules of oral topotecan in combination with pazopanib in patients with advanced solid tumours. Methods: Stage I of this study was to determine whether there was an impact of pazopanib on topotecan exposure. In stage II, the MTD and safety profile of oral topotecan given weekly on days 1, 8 and 15 in a 28-day cycle; or daily-times-five on days 1-5 in a 21-day cycle, both in combination with daily pazopanib, were explored. Results: In total, 67 patients were enroled. Pazopanib co-administration caused a substantial increase in exposure to total topotecan (1.7-fold) compared with topotecan alone, which is considered clinically relevant. Topotecan had no effect on pazopanib concentrations. Safety findings were consistent with the known profile of both agents. There were three drug-related deaths, liver failure, tumour haemorrhage and myelosuppression. Two patients experienced dose-limiting toxicities (DLTs; hand-foot syndrome, myelosuppression and diarrhoea) on the weekly topotecan schedule and four patients experienced DLTs (myelosuppression) on the daily-times-five topotecan schedule. When combined with pazopanib, 800 mg daily, the recommended doses for oral topotecan are: 8 mg weekly and 2.5 mg daily-times-five. Seven of eight patients with partial response had platinum-resistant ovarian cancer. In addition, 54% of patients had stable disease with 22% stable for 6 months. Conclusions: Total topotecan exposure is 1.7-fold higher when co-administered with pazopanib. Both schedules of administration were tolerated and would permit further evaluation, especially the weekly schedule.

Background: AZD3514 is a first-in-class, orally bio-available, androgen-dependent and -independent androgen receptor inhibitor and selective androgen-receptor down-regulator (SARD). Methods: In study 1 and 2, castration-resistant prostate cancer (CRPC) patients (pts) were initially recruited into a once daily (QD) oral schedule (A). In study 1, pharmacokinetic assessments led to twice daily (BID) dosing (schedule B) to increase exposure. Study 2 explored a once daily schedule. Results: In study 1, 49 pts were treated with escalating doses of AZD3514 (A 35 pts, B 14 pts). Starting doses were 100 mg (A) and 1000 mg (B). The AZD3514 formulation was switched from capsules to tablets at 1000 mg QD. 2000 mg BID was considered non-tolerable due to grade (G) 2 toxicities (nausea [N], vomiting [V]). No adverse events (AEs) met the dose-limiting toxicity (DLT) definition. Thirteen pts received AZD3514 in study 2, with starting doses of 250 mg QD. The most frequent drug-related AEs were N: G1/2 in 55/70 pts (79 %); G3 in 1 pt (1.4 %); & V: G1/2 in 34/70 pts (49 %) & G3 in 1 pt (1.4 %). PSA declines (≥50 %) were documented in 9/70 patients (13 %). Objective soft tissue responses per RECIST1.1 were observed in 4/24 (17 %) pts in study 1. Conclusion: AZD3514 has moderate anti-tumour activity in pts with advanced CRPC but with significant levels of nausea and vomiting. However, anti-tumour activity as judged by significant PSA declines, objective responses and durable disease stabilisations, provides the rationale for future development of SARD compounds.

Background Breast cancer is the most common type of cancer among women worldwide. In low and middle-income countries (LMICs), appropriate selection of medicines on national essential medicines lists (NEMLs) is a first step towards adequate access to treatment. We studied selection of systemic treatments for breast cancer on NEMLs and assessed its alignment with treatment guidelines for different types of early and advanced breast cancer. Furthermore, influence of country characteristics on the selection was investigated. Method NEMLs from 75 LMICs were studied for inclusion of all components of therapy in each stage of breast cancer according to international consensus guidelines. The results were then grouped by income level, WHO region and the NEMLs’ release date. Non parametric tests were used for statistical analysis. Results Unlike HER2-targeted therapies (

Purpose: The combination of an mTOR inhibitor with 5-fluorouracil-based anticancer therapy is attractive because of preclinical evidence of synergy between these drugs. According to our phase I study, the combination of capecitabine and everolimus is safe and feasible, with potential activity in pancreatic cancer patients. Methods: Patients with advanced adenocarcinoma of the pancreas were enrolled. Eligible patients had a WHO performance status 0-2 and adequate hepatic and renal functions. The treatment regimen consisted of capecitabine 1000 mg/m2 BID day 1-14 and everolimus 10 mg daily (5 mg BID) in a continuous 21-day schedule. Tumor assessment was performed with CT-scan every three cycles. Primary endpoint was response rate (RR) according to RECIST 1.0. Secondary endpoints were progression-free survival, overall survival and 1-year survival rate. Results: In total, 31 patients were enrolled. Median (range) treatment duration with everolimus was 76 days (1-431). Principal grade 3/4 toxicities were hyperglycemia (45 %), hand-foot syndrome (16 %), diarrhea (6 %) and mucositis (3 %). Prominent grade 1/2 toxicities were anemia (81 %), rash (65 %), mucositis (58 %) and fatigue (55 %). RR was 6 %. Ten patients (32 %) had stable disease resulting in a disease control rate of 38 %. Median overall survival was 8.9 months (95 % CI 4.6-13.1). Progression-free survival was 3.6 months (95 % CI 1.9-5.3). Conclusions: The oral regimen with the combination of capecitabine and everolimus is a moderately active treatment for patients with advanced pancreatic cancer, with an acceptable toxicity profile at the applied dose level.

Item does not contain fulltext AIMS: E7070 is a novel, sulphonamide anticancer agent currently under clinical development for the treatment of solid tumours. The aim of this study was to develop and validate limited sampling strategies for the prediction of E7070 exposure in two different treatment schedules for phase II studies using the Bayesian estimation approach. METHODS: Data from two phase I dose finding studies were used in which E7070 was administered either as a single 1 h infusion or as a daily 1 h infusion for 5 days. Plasma concentration-time data from 75 patients were randomly divided into an index data set, used for the development of the strategies, and a validation data set. Population pharmacokinetic parameters were derived on the basis of the index data set. The D-optimality algorithm was used for the selection of optimal time points for both treatment schedules. The developed strategies were compared by assessment of their predictive performance of exposure, expressed as AUC (area under the plasma concentration vs time curve), in the validation data set. RESULTS: The developed population pharmacokinetic model comprised three compartments, with saturable distribution to one peripheral compartment and both linear and saturable elimination from the central compartment. For the 1 h infusion, a four sample strategy was selected which resulted in unbiased and accurate predictions of AUC (bias 0.74%, precision 13%). A five sample strategy was generated for the daily times five schedule yielding unbiased (bias 3.2%) and precise (12% precision) predictions of AUC. CONCLUSIONS: Optimal sampling strategies were developed and validated for estimation of E7070 exposure in two different treatment schedules. Both schedules enabled accurate and unbiased predictions of AUC.

Plitidepsin is an anti-cancer drug currently evaluated in phase I/II/III clinical trials. This article describes the development and validation of a bioanalytical assay to quantify plitidepsin in human plasma, urine and whole blood using HPLC-MS/MS. The analyte was extracted from the matrix by liquid-liquid extraction using tert-butyl methyl ether. Final extracts were injected onto a C18 column, gradient elution was applied for chromatographic separation and detection was performed on a triple quadrupole mass spectrometer operating in the positive ion mode. The assay was linear over the range 0.1-100ng/mL, with acceptable accuracy and precision values. This is the first reported bioanalytical assay quantifying plitidepsin using a stable isotopically labelled standard, achieving a lower limit of quantification of 0.1ng/mL in all three matrices, allowing the quantification of trace levels of plitidepsin, and accomplishing this in an analysis time of two minutes only. The presented method was successfully applied in a mass balance study with plitidepsin in patients with advanced cancer.

BACKGROUND: Plasma exposure of sunitinib shows large inter-individual variation. Therefore, a pharmacokinetic (PK) study was performed to determine safety and feasibility of sunitinib dosing based on PK levels. METHODS: Patients were treated with sunitinib 37.5 mg once daily. At days 15 and 29 of treatment, plasma trough levels of sunitinib and N-desethyl sunitinib were measured. If the total trough level (TTL) was

BACKGROUND: High cancer mortality rates in low- and middle-income countries (LMICs) have raised concerns regarding access to oncology medicines. Essential medicines are those which satisfy the primary health care needs and provide a basis for public procurement or reimbursement decisions in LMICs. We explored selection of oncology medicines in LMICs through investigating national essential medicines lists (NEMLs) for cancer treatments. METHODS: Recently updated NEMLs were retrieved for 76 countries. Oncology medicines were classified based on therapeutic categories. Countries were clustered based on geographic regions, income levels and burden of cancer (mortality and morbidity). Indicators of frequency (number of medicines), diversity (number of therapeutic (sub)categories) and more importantly absence were measured and compared across countries using parametric and nonparametric tests. RESULTS: The overall median number of oncology medicines on NEMLs was 16 (interquartile range = 23) chosen predominantly from subcategories of 'antineoplastic agents', with substantial variation across regions and income groups. Five countries did not select any oncology medicine and 68% did not have any 'hormones and related agents' on their NEMLs. Newer technologies like targeted therapies were infrequently incorporated. The cluster of countries suffering most from the burden of cancer selected more essential oncology medicines and diversified further. CONCLUSION: The observed selection of oncology essential medicines can reflect insufficiencies and inequalities in access to cancer treatments at least in the public sector of LMICs. Further resources need to be allocated from governments and international organizations to tackle the problem of access to oncology medicines in these countries.

BACKGROUND: The intestinal uptake of the taxanes paclitaxel and docetaxel is seriously hampered by drug efflux through P-glycoprotein (P-gp) and drug metabolism via cytochrome P450 (CYP) 3A. The resulting low oral bioavailability can be boosted by co-administration of P-gp or CYP3A4 inhibitors. METHODS: Paclitaxel or docetaxel (10 mg/kg) was administered to CYP3A4-humanised mice after administration of the P-gp inhibitor elacridar (25 mg kg(-1)) and the CYP3A inhibitor ritonavir (12.5 mg kg(-1)). Plasma and brain concentrations of the taxanes were measured. RESULTS: Oral co-administration of the taxanes with elacridar increased plasma concentrations of paclitaxel (10.7-fold, P

Contains fulltext : 136010.pdf (Publisher’s version ) (Open Access) Background:Plasma exposure of sunitinib shows large inter-individual variation. Therefore, a pharmacokinetic (PK) study was performed to determine safety and feasibility of sunitinib dosing based on PK levels.Methods:Patients were treated with sunitinib 37.5 mg once daily. At days 15 and 29 of treatment, plasma trough levels of sunitinib and N-desethyl sunitinib were measured. If the total trough level (TTL) was

Population pharmacokinetic-dynamic analysis was prospectively integrated in the clinical phase If programme of EO9 to determine the population pharmacokinetic profile in a larger population of patients, to estimate individual patient pharmacokinetic parameters, and to investigate relationships between drug exposure and clinical outcome. A sparse sampling method was developed, which involved three sampling times, and was implemented during course 1. A Bayesian algorithm was used to estimate individual pharmacokinetic parameters, In particular total plasma clearance (CL) of EO9 and area under the curve (AUC). In total, samples were collected of 85 (65%) of the patients. Pharmacokinetic evaluation was successful in 61 (72%) of the sampled patients. CL of EO9 showed substantial variability (median 5.08 l/min; range 2.67-6.42) and was of the same magnitude as in the phase I study where full pharmacokinetic profiles were used. No significant relationships were noticed between exposure parameters and safety, but overall limited toxicity was observed. No tumor responses were documented. Prospective implementation of large-scale population pharmacokinetic-dynamic analysis is feasible and may generate important findings, In particular when tumor responses and relevant toxicity are observed. [(C) 2001 Lippincott Williams & Wilkins.].

Dissolution from the pharmaceutical formulation is a prerequisite for complete and consistent absorption of any orally administered drug, including anticancer agents (oncolytics). Poor dissolution of an oncolytic can result in low oral bioavailability, high variability in blood concentrations and with that suboptimal or even failing therapy. This review discusses pharmaceutical formulation aspects and absorption pharmacokinetics of currently licensed orally administered oncolytics. In nearly half of orally dosed oncolytics poor dissolution is likely to play a major role in low and unpredictable absorption. Dissolution-limited drug absorption can be improved with a solid dispersion which is a formulation method that induces super-saturated drug dissolution and with that it enhances in vivo absorption. This review discusses formulation principles with focus on the solid dispersion technology and how it works to enhance drug absorption. There are currently three licensed orally dosed oncolytics formulated as a solid dispersion (everolimus, vemurafenib and regorafenib) and these formulations result in remarkably improved dissolution and absorption compared to what can be achieved with conventional formulations of the respective oncolytics. Because of the successful implementation of these three solid dispersion formulations, we encourage the application of this formulation method for poorly soluble oral oncolytics.

Aims: To investigate the population pharmacokinetics and pharmacodynamics of doxorubicin and cyclophosphamide in breast cancer patients. Patients and methods: Sixty-five female patients with early or advanced breast cancer received doxorubicin 60 mg/m2 over 15 minutes followed by cyclophosphamide 600 mg/m2 over 15 minutes. The plasma concentration-time data of both drugs were measured, and the relationship between drug pharmacokinetics and neutrophil counts was evaluated using nonlinear mixed-effect modelling. Relationships were explored between drug exposure (the area under the plasma concentration-time curve [AUC]), toxicity and tumour response. Results: Fifty-nine patients had complete pharmacokinetic and toxicity data. In 50 patients with measurable disease, the objective response rate was 60%, with complete responses in 6% of patients. Both doxorubicin and cyclophosphamide pharmacokinetics were associated with neutrophil toxicity. Cyclophosphamide exposure (the AUC) was significantly higher in patients with at least stable disease (n = 44) than in patients with progressive disease (n = 6; 945 μmol·h/L [95% CI 889, 1001] vs 602 μmol·h/L [95% CI 379, 825], p = 0.0002). No such correlation was found for doxorubicin. Body surface area was positively correlated with doxorubicin clearance; AST and patient age were negatively correlated with doxorubicin clearance; creatinine clearance was positively correlated with doxorubicinol clearance; and occasional concurrent use of carbamazepine was positively correlated with cyclophosphamide clearance. Conclusions: The proposed inhibitory population pharmacokinetic-pharmacodynamic model adequately described individual neutrophil counts after administration of doxorubicin and cyclophosphamide. In this patient population, exposure to cyclophosphamide, as assessed by the AUC, might have been a predictor of the treatment response, whereas exposure to doxorubicin was not. A prospective study should validate cyclophosphamide exposure as a predictive marker for the treatment response and clinical outcome in this patient group. © 2007 Adis Data Information BV. All rights reserved. 46 12 1051 1068

A method for the quantification of two peptide HIV-1 fusion inhibitors (enfuvirtide, T-20 and tifuvirtide, T-1249) and one metabolite of enfuvirtide (M-20) in human plasma has been developed and validated, using liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS). The analytes were extracted from plasma by solid-phase extraction (SPE) on vinyl-copolymer cartridges. Chromatographic separation of the peptides was performed on a Symmetry 300 C(18) column (50mmx2.1mm I.D., particle size 3.5 microm), using a water-acetonitrile gradient containing 0.25% (v/v) formic acid. The triple quadrupole mass spectrometer was operated in the positive ion-mode and multiple reaction monitoring (MRM) was used for peak detection. Deuterated (d60) enfuvirtide and (d50) tifuvirtide were used as internal standards. The assay was linear over a concentration range of 20-10,000 ng/ml for enfuvirtide and tifuvirtide and of 20-2000 ng/ml for M-20. Intra- and inter-assay precisions and deviations from the nominal concentrations were

S-1 is a new oral fluorinated pyrimidine derivate, in which the oral 5-fluorouracil (5-FU) prodrug, tegafur, was combined with two 5-FU-modulating substances, 5-chloro-2,4-dihydroxypyridine (gimeracil), and potassium oxonate (oteracil), at a molar ratio of 1:0.4:1. The final mechanism of action is exerted by 5-FU. The present study is the first European phase II trial of S-1 in gastric cancer. The primary study objectives were the safety, toxicity and activity of S-1 in non-pretreated patients with gastric cancer. The secondary objective was the duration of response. Patients had to have histologically- or cytologically-verified metastatic or locally advanced, unresectable gastric cancer; S-1 was administered orally twice daily at 40, then 35 mg/m2 for 28 days every 5 weeks. The starting dose of 40 mg/m2 was found to be intolerable due to significant non-haematological toxicity, and this dose was rapidly reduced to 35 mg/m2 twice daily. Of the 7 patients enrolled at the 40 mg/m2 level, only 3 were evaluable. At 35 mg/m2, a response rate of 26.1% (95% Confidence Interval (CI) 12.0-45.1%) in 23 enrolled patients, and 31.6% (C.I. 14.7-53.0%) in 19 evaluable patients according to an independent radiology review, was found. The median duration of response at 35 mg/m2 (6 patients) was 223 days (range, 108-828 days), and of stable disease was 111 days (range 68-411 days). S-1 can be administered with an acceptable safety and toxicity in European patients at a dose of 35 mg/m2 days 1 - 28 every 5 weeks and is associated with a moderate response rate similar to the results achieved with other fluoropyrimidines. © 2003 Elsevier Science Ltd. All rights reserved. 39 9 1264 1270

Population pharmacokinetic-dynamic analysis was prospectively integrated in a broad phase II program of lurtotecan (GI147211), a novel camptothecin derived topoisomerase I inhibitor, to determine the population pharmacokinetic profile in a larger population, to estimate individual pharmacokinetic parameters and to investigate relationships with clinical outcome. A sparse sampling method was applied during course one, which involved two sampling time-points. A Bayesian algorithm was used to estimate individual pharmacokinetic parameters, in particular total plasma clearance (CL) and volume of distribution. In total, samples were collected of 109 (63%) of 173 patients. Pharmacokinetic-dynamic evaluation could be carried out successfully in 85 (78%) of the sampled patients. CL of lurtotecan showed substantial variability (mean 87 +/- 28 L/h) and was of the same magnitude as in the phase I studies where full pharmacokinetic curves were used. Residual variability in the population estimate of CL was 9.9%. No significant relationships were observed between exposure parameters and toxicity nor likelihood of tumor response, however the latter relationship may well have been obscured by the heterogeneity of the studied population. Prospective implementation of large scale population pharmacokinetic-dynamic analysis is feasible and important to establish whether interpatient variability in drug exposure is a major determinant of toxicity or activity. Invest New Drugs

BACKGROUND: Capecitabine is an established treatment alternative to intravenous 5-fluorouracil (5-FU) for patients with rectal cancer receiving chemoradiotherapy. Its place in the treatment of locally advanced anal carcinoma (AC), however, remains undetermined. We investigated whether capecitabine is as effective as 5-FU in the treatment of patients with locally advanced AC. METHODS: One hundred and five patients with squamous cell AC stage T2-4 (T2>4 cm), N0-1, M0 or T1-4, N2-3, M0, were included in this retrospective study. Forty-seven patients were treated with continuous 5-FU (750 mg m(-2)) on days 1-5 and 29-33, mitomycin C (MMC, 10 mg m(-2)) on day 1, and radiotherapy; 58 patients were treated with capecitabine (825 mg m(-2) b.i.d. on weekdays), MMC (10 mg m(-2)) on day 1, and radiotherapy. The primary end points of the study were: clinical complete response rate, locoregional control (LRC) and overall survival (OS). Secondary end points were: colostomy-free survival (CFS), toxicity and associations of genetic polymorphisms (GSTT1, GSTM1, GSTP1 and TYMS) with outcome and toxicity. RESULTS: Clinical complete response was achieved in 41/46 patients (89.1%) with 5-FU and in 52/58 patients (89.7%) with capecitabine. Three-year LRC was 76% and 79% (P=0.690, log-rank test), 3-year OS was 78% and 86% (P=0.364, log-rank test) and CFS was 65% and 79% (P=0.115, log-rank test) for 5-FU and capecitabine, respectively. GSTT1 and TYMS genotypes were associated with severe (grade 3-4) toxicity. CONCLUSIONS: Capecitabine combined with MMC and radiotherapy was equally effective as 5-FU-based chemoradiotherapy. This study shows that capecitabine can be used as an acceptable alternative to 5-FU for the treatment of AC.

BACKGROUND: High cancer mortality rates in low- and middle-income countries (LMICs) have raised concerns regarding access to oncology medicines. Essential medicines are those which satisfy the primary health care needs and provide a basis for public procurement or reimbursement decisions in LMICs. We explored selection of oncology medicines in LMICs through investigating national essential medicines lists (NEMLs) for cancer treatments. METHODS: Recently updated NEMLs were retrieved for 76 countries. Oncology medicines were classified based on therapeutic categories. Countries were clustered based on geographic regions, income levels and burden of cancer (mortality and morbidity). Indicators of frequency (number of medicines), diversity (number of therapeutic (sub)categories) and more importantly absence were measured and compared across countries using parametric and nonparametric tests. RESULTS: The overall median number of oncology medicines on NEMLs was 16 (interquartile range = 23) chosen predominantly from subcategories of 'antineoplastic agents', with substantial variation across regions and income groups. Five countries did not select any oncology medicine and 68% did not have any 'hormones and related agents' on their NEMLs. Newer technologies like targeted therapies were infrequently incorporated. The cluster of countries suffering most from the burden of cancer selected more essential oncology medicines and diversified further. CONCLUSION: The observed selection of oncology essential medicines can reflect insufficiencies and inequalities in access to cancer treatments at least in the public sector of LMICs. Further resources need to be allocated from governments and international organizations to tackle the problem of access to oncology medicines in these countries.

Background: GI147211 is a water-soluble synthetic analogue of camptothecin showing promising in vivo and in vitro antitumor activity and an acceptable toxicity profile. Patients and methods: Between April 1995 and November 1996, 67 eligible patients with pretreated breast cancer (25 patients) and chemo-naive colorectal (19 patients) and non-small-cell lung cancer (23 patients) were entered into three multicentric, non-randomized phase II trials. Treatment schedule consisted of intravenous GI147211 administered at a dose of 1.2 mg/m2/day for five consecutive days every three weeks. Results: Hematological toxicity was common with grade 3-4 neutropenia in 54% of patients and neutropenic fever together or not associated with infection in 14.5% of patients. Grade 3-4 thrombocytopenia and grade 2-4 anemia were observed in 20% and in 68% of patients, respectively. Non-hematological toxicity was generally mild to moderate and consisted mainly of gastrointestinal toxicity, asthenia and alopecia. A dose-escalation to 1.5 mg/m2/d was feasible in 17 (25%) patients. The antitumor activity of GI147211 was moderate in breast cancer patients (3 partial responses (PRs), response rate (RR) 13%) and minimal in non-small cell lung cancer patients (2 PRs, RR 9%). No objective responses were obtained in colorectal patients. Conclusions: GI147211, at the dose and schedule employed in this study, showed an acceptable safety profile but a modest antitumor activity in the examined tumor types. 11 7 793 797

International audience; The study of metal complexes for the treatment of cancer diseases has resulted in the identification of some unique properties of ruthenium-based compounds. Among these inorganic-based agents, two of them, namely the ruthenium(III) drugs NAMI-A and KP1019 have undertaken with some success the clinical evaluations of phase I and preliminary phase II trials in patients. Here we highlight the strategies that have led to the discovery of metal-based (NAMI-A and KP1019) and of organometallic (RM175, RAPTA-T, RDC11 and DW1/2) ruthenium-based complexes, and we report their main biological/pharmacological characteristics and expectations for further development.