Biomedical subjects

Hilde Rosing

Publications and source records attributed to Hilde Rosing.

36 records · Page 2Linked to original sources

PubMed2004

Simultaneous quantification of cyclophosphamide, 4-hydroxycyclophosphamide, N,N',N"-triethylenethiophosphoramide (thiotepa) and N,N',N"-triethylenephosphoramide (tepa) in human plasma by high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry.

The alkylating agents cyclophosphamide (CP) and N, N', N"-triethylenethiophosphoramide (thiotepa) are often co-administered in high-dose chemotherapy regimens. Since these regimens can be complicated by the occurrence of severe and sometimes life-threatening toxicities, pharmacokinetically guided administration of these compounds, to reduce variability in exposure, may lead to improved tolerability. For rapid dose adaptations during a chemotherapy course, we have developed and validated an assay, using liquid chromatography coupled with electrospray tandem mass spectrometry (LC/MS/MS), for the routine quantification of CP, thiotepa and their respective active metabolites 4-hydroxycyclophosphamide (4OHCP) and N, N', N"-triethylenephosphoramide (tepa) in plasma. Because of the instability of 4OHCP in plasma, the compound is derivatized with semicarbazide (SCZ) immediately after sample collection and quantified as 4OHCP-SCZ. Sample pretreatment consisted of protein precipitation with a mixture of methanol and acetronitrile using 100 microl of plasma. Chromatographic separation was performed on an Zorbax Extend C18 column (150 x 2.1 mm i.d., particle size 5 microm), with a quick gradient using 1 mM ammonia solution and acetonitrile, at a flow-rate of 0.4 ml min(-1). The analytical run time was 10 min. The triple quadrupole mass spectrometer was operating in the positive ion mode and multiple reaction monitoring was used for drug quantification. The method was validated over the concentration ranges 200-40,000 ng ml(-1) for CP, 50-5000 ng ml(-1) for 4OHCP-SCZ and 5-2500 ng ml(-1) for thiotepa and tepa, using 100 microl of human plasma. These dynamic concentration ranges proved to be relevant in daily practice. Hexamethylphosphoramide was used as an internal standard. The coefficients of variation were <12% for both intra-day and inter-day precisions for each compound. Mean accuracies were also between the designated limits (+/- 15%). This robust and rapid LC/MS/MS assay is now successfully applied for routine therapeutic drug monitoring of CP, thiotepa and their metabolites in our hospital.

Antineoplastic Agents, Alkylating↗

PubMed2004

Quantitative analysis of the P-glycoprotein inhibitor Elacridar (GF120918) in human and dog plasma using liquid chromatography with tandem mass spectrometric detection.

A liquid chromatographic/tandem mass spectrometric (LC/MS/MS) method for the determination of the P-glycoprotein and breast cancer resistance protein inhibitor Elacridar in human and dog plasma is described. The internal standard was stable isotopically labelled Elacridar. Sample pretreatment involved liquid-liquid extraction with tert-butyl methyl ether. Analysis of Elacridar and internal standard was performed by reversed-phase LC on a basic stable minibore analytical column with an eluent consisting of acetonitrile and aqueous ammonia. An API-2000 triple-quadrupole mass spectrometer with an electrospray ion source was used in the positive-ion multiple reaction monitoring mode. The run time per sample was only 6 min. The method is sensitive and specific, with a dynamic range from 1 to 500 ng ml(-1) from 100 microl of human or dog plasma. The accuracy of the method was within 15% bias and the precision was lower than 15% for all tested concentration levels and in both matrices. The method is simple and the liquid-liquid extraction produces clean samples. This method was successfully applied to support the pharmacokinetics of a clinical trial in which orally applied Elacridar was used as a bioavailability enhancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2004

Quantitative analysis of D-24851, a novel anticancer agent, in human plasma and urine by liquid chromatography coupled with tandem mass spectrometry.

The development of a liquid chromatography/tandem mass spectrometric assay for the quantitative analysis of the novel tubulin inhibitor D-24851 in human plasma and urine is described. D-24851 and the deuterated internal standard were extracted from 250 microL of plasma or urine using hexane/ether (1:1, v/v). Subsequently, 10-microL aliquots of reconstituted extracts were injected onto an Inertsil ODS analytical column (50 x 2.0 mm i.d., 5 microm particle size). An eluent consisting of methanol/5 mM ammonium acetate, 0.004% formic acid in water (80:20, v/v) was pumped at a flow rate of 0.2 mL/min. An API 365 triple quadrupole mass spectrometer was used in the multiple reaction monitoring mode for sensitive detection. For human plasma a dynamic range of 1-1000 ng/mL was validated, and for human urine a range of 0.25-50 ng/mL. Validation was performed according to the most recent FDA guidelines and all results were within requirements. The assay has been successfully applied to support a phase I clinical trial with orally administered D-24851.

Acetamides↗

PubMed2004

Quantitative determination of the novel anticancer drug E7070 (indisulam) and its metabolite (1,4-benzenedisulphonamide) in human plasma, urine and faeces by high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry.

E7070 (indisulam) is a novel anticancer drug currently undergoing clinical investigation. We present a sensitive and specific method for the quantitative determination of E7070 and its metabolite M1 (1,4-benzenedisulphonamide) in human plasma, urine and faeces. The analytes and their tetra-deuterated analogues, which were used as internal standards, were isolated from the biological matrix by solid-phase extraction with OASIS cartridges (0.5 mL plasma or 1 mL urine) and by liquid-liquid extraction with ethyl acetate at pH 5 (1 mL faecal homogenate). The analytes were separated on a C8 reversed-phase chromatographic column and analyzed using electrospray ionization and tandem mass spectrometric detection in the negative ion mode. The validated concentration ranges in plasma were 0.1-20 microg/mL for E7070 and 0.01-2 microg/mL for M1. In urine and faecal homogenate, a concentration range from 0.05-10 microg/mL or microg/g, respectively, was validated for both analytes. Validation of the plasma assay was performed according to the most recent FDA guidelines. The assay fulfilled all generally accepted requirements for linearity (r > 0.99, residuals between -8 and 10%), accuracy (-13.5 to 1.4%) and precision (all less than 11%) in the tested matrices. We investigated recovery, stability (working solutions at -20 degrees C and at room temperature, biological matrices at -20 degrees C, room temperature and after 3 freeze/thaw cycles; final extracts at room temperature) and robustness. All these parameters were found acceptable. This method is suited for mass balance studies or therapeutic drug monitoring, as demonstrated by a case example showing plasma concentrations and cumulative excretion of E7070 and M1 in urine and faeces. Furthermore, we show the presence of E7070 metabolites in patient urine.

Antineoplastic Agents↗

PubMed2003

Simple and rapid method for the simultaneous determination of the non-nucleoside reverse transcriptase inhibitors efavirenz and nevirapine in human plasma using liquid chromatography.

Efavirenz and nevirapine are non-nucleoside reverse transcriptase inhibitors for the treatment of HIV-1-infected individuals. A simple and rapid high-performance liquid chromatographic method for the simultaneous quantification of efavirenz and nevirapine in human plasma suitable for therapeutic drug monitoring is described. Sample pre-treatment consisted of protein precipitation with acetonitrile and subsequently dilution with distilled water. The drugs were separated from endogenous compounds by isocratic reversed-phase high-performance liquid chromatography with ultraviolet detection at 275 nm. The method was validated over the therapeutically relevant concentration range of 0.05-15.0 mg l(-1) and 0.25-15.0 mg l(-1) for efavirenz and nevirapine, respectively, using a volume of 100 microl of plasma. The calibration curves were linear over this concentration range. Carbamazepine was used as internal standard. The assay proved to be accurate (accuracies varied between -12.7 and 8.5%) and precise (intra- and inter-assay precisions were less then 5.9%). The tested batches of control human plasma and frequently co-administered drugs did not interfere with the described methodology. Efavirenz and nevirapine were stable under various relevant storage conditions. This validated assay is suited for use in pharmacokinetic studies with efavirenz and nevirapine and can readily be implemented in the setting of a hospital laboratory for the monitoring of efavirenz and nevirapine concentrations.

Alkynes↗

PubMed2003

Pharmacokinetic study of docetaxel in intraoperative hyperthermic i.p. chemotherapy for ovarian cancer.

The purpose of this study was to evaluate the pharmacokinetics and toxicity of docetaxel in continuous hyperthermic perfusion peritoneal chemotherapy (CHPPC) after cytoreductive surgery for peritoneal involvement of gynecological malignancies, mainly ovarian cancer. Eighteen patients, with a mean age of 64 years (range 51-80), underwent cytoreductive surgery and subsequent CHPPC with 75 mg/m2 docetaxel at 41-43 degrees C. One patient was treated twice. In eight cases, peritoneal fluid and blood samples were obtained for pharmacokinetic analysis. Death occurred in two heavily pretreated elderly patients with a high volume i.p. tumor recurrence, probably reflecting poor patient selection (mortality rate 10.5%). Other complications, mainly minor, were recorded after 63% of the procedures. Hematological docetaxel-induced toxicity was limited, while the incidence of wound complications was relatively high and probably caused by the direct exposure of the wound to docetaxel during CHPPC. The maximal i.p. versus plasma concentration ratio ranged from 17 to 95 (average 45), while the i.p. versus systemic exposure ratio varied between 105 and 555 (average 207). We conclude that the use of docetaxel in CHPPC following cytoreductive surgery seems feasible and results in a high i.p. versus systemic exposure ratio. The AUC for the peritoneal cavity is on average 13-27 times higher after i.p. administration of 75 mg/m2 during CHPPC than the AUC achieved in the systemic compartment after i.v. administration of the recommended dose of 100 mg/m2, while docetaxel-induced systemic toxicity is highly limited.

Aged↗

PubMed2003

High-performance liquid chromatographic analysis of the anticancer drug irinotecan (CPT-11) and its active metabolite SN-38 in human plasma.

A rapid, sensitive, and specific high-performance liquid chromatography (HPLC) method for the simultaneous determination of irinotecan (CPT-11) and its active metabolite SN-38 in human plasma is described. The analytes are quantified as the totals of their carboxylate and lactone form. The sample pretreatment consisted of a simple protein precipitation with acetonitrile-methanol (1:1, v/v), after which CPT-11 and SN-38 were quantitatively converted to their carboxylate form by adding 0.01 mol/L sodium tetraborate (pH, 9). Chromatography was carried out on a Zorbax SB-C18 column with fluorescence detection. The method has been validated, and stability tests under various clinically relevant conditions have been performed. The lower limit of quantification (LLOQ) was 5.0 ng/mL for CPT-11 and 0.5 ng/mL for SN-38. Standard concentration ranges were linear between 5 and 1,500 ng/mL for CPT-11 and between 0.5 and 100 ng/mL for SN-38. This assay is simple, rapid, and very useful for therapeutic monitoring of CPT-11 and SN-38.

Antineoplastic Agents↗

PubMed2002

The breast cancer resistance protein protects against a major chlorophyll-derived dietary phototoxin and protoporphyria.

The breast cancer resistance protein (BCRPABCG2) is a member of the ATP-binding cassette family of drug transporters and confers resistance to various anticancer drugs. We show here that mice lacking Bcrp1Abcg2 become extremely sensitive to the dietary chlorophyll-breakdown product pheophorbide a, resulting in severe, sometimes lethal phototoxic lesions on light-exposed skin. Pheophorbide a occurs in various plant-derived foods and food supplements. Bcrp1 transports pheophorbide a and is highly efficient in limiting its uptake from ingested food. Bcrp1(-/-) mice also displayed a previously unknown type of protoporphyria. Erythrocyte levels of the heme precursor and phototoxin protoporphyrin IX, which is structurally related to pheophorbide a, were increased 10-fold. Transplantation with wild-type bone marrow cured the protoporphyria and reduced the phototoxin sensitivity of Bcrp1(-/-) mice. These results indicate that humans or animals with low or absent BCRP activity may be at increased risk for developing protoporphyria and diet-dependent phototoxicity and provide a striking illustration of the importance of drug transporters in protection from toxicity of normal food constituents.

ATP Binding Cassette Transporter, Subfamily G, Mem↗

PubMed2002

Development of an optimal pharmacokinetic sampling schedule for rubitecan administered orally in a daily times five schedule.

PURPOSE: Our aim was to develop an optimal sampling strategy for the description of the pharmacokinetics of rubitecan and its active metabolite 9-aminocamptothecin (9-AC) for use in phase II/III studies with oral rubitecan administered in a daily times five schedule. METHODS: Concentration-time data of rubitecan and 9-AC were obtained from 14 patients who had received 1.5 mg/m(2) per day rubitecan orally. Population pharmacokinetic analysis of both the parent and the metabolite was performed using the nonlinear mixed effect modelling program (NONMEM). Optimal sampling points were selected on the basis of the assessed population pharmacokinetic parameters using a D-optimality algorithm. RESULTS: The pharmacokinetics of both rubitecan and 9-AC were adequately described with a one-compartment model. The absorption rate constant, apparent volume of distribution and apparent clearance of rubitecan were 0.81 h(-1), 50 l and 1.7 l/h, respectively. For 9-AC the corresponding values of the apparent volume of distribution and the elimination rate constant were 51 l and 0.102 h(-1). Interindividual variability of the pharmacokinetic parameters ranged from 38% to 49%. For the first dose, optimal sampling points were 1, 3, 5, 8 and 24 h after dosing. Monte Carlo simulations indicated that the sampling schedule produced parameter estimates which were unbiased and precise. CONCLUSIONS: An optimal sampling schedule was derived which allowed assessment of the pharmacokinetic parameters of both the parent compound and its metabolite 9-AC after oral administration of rubitecan.

Administration, Oral↗

PubMed2002

Clinical pharmacokinetics, pharmacodynamics and metabolism of the novel matrix metalloproteinase inhibitor ABT-518.

PURPOSE: To investigate the pharmacokinetics, pharmacodynamics and metabolism of the novel matrix metalloproteinase (MMP) inhibitor ABT-518. METHODS: Plasma and urine samples were obtained from six patients included in a phase I trial in which ABT-518 was given once daily via the oral route. Samples were analyzed by LC-MS/MS, ELISA and immunocapture assay. The pharmacokinetics of the parent compound and of detectable metabolites were calculated. RESULTS: After a single dose of ABT-518 peak plasma levels were reached within 4-8 h. ABT-518 had an estimated clearance (Cl/F) of approximately 3 l/h, an estimated volume of distribution (V/F) of over 70 l and a terminal half-life (T(1/2)) of 20 h. At least six different metabolites were formed. Pharmacodynamic analysis for angiogenic growth factors (bFGF and VEGF) showed plasma and urine levels in the picogram range and for total MMP-9 and MMP-2 or MMP-9 activity showed plasma and urine levels in the nanogram range. CONCLUSIONS: The MMP inhibitor ABT-518 is extensively metabolized in humans. No significant correlations between pharmacokinetics and pharmacodynamics could be established.

Adult↗

PubMed2002

Determination of 9-nitrocamptothecin and its metabolite 9-aminocamptothecin in human plasma using high-performance liquid chromatography with ultraviolet and fluorescence detection.

A high-performance liquid chromatography assay is described for the determination of the investigational anti-cancer drug 9-nitrocamptothecin (9-NC) and its metabolite 9-aminocamptothecin (9-AC) as the total of their lactone and carboxylate forms. The sample pre-treatment consisted of a deproteinisation step and a quantitative acid-catalyzed conversion of all 9-NC and 9-AC into their lactone forms and a subsequent solid-phase extraction. Redissolved extracts were analyzed on a Prodigy analytical column, using a mixture of methanol-phosphate buffer (pH 2.5). Detection was concomitantly performed with UV for 9-NC and fluorimetrically for 9-AC. The lower limit of quantifications were 10 ng/ml and 2.5 ng/ml for the determination of 9-NC and 9-AC, respectively, using 500 microl of plasma. The presented method was successfully applied to a clinical pharmacokinetic study.

Camptothecin↗

PubMed2002

Urinary and fecal excretion of topotecan in patients with malignant solid tumours.

PURPOSE: The objectives of the study were to determine the pharmacokinetics and routes of excretion of topotecan following intravenous or oral administration to patients with refractory solid tumours. METHODS: Patients were randomized to receive either oral (2.3 mg/m(2)) or intravenous (1.5 mg/m(2)) topotecan once daily for 5 days in course 1. Patients who received in course 1 oral topotecan received in course 2 intravenous topotecan on day 1 followed by oral topotecan on days 2 to 5. Patients who received in course 1 intravenous topotecan received in course 2 oral topotecan once daily for 5 days. Plasma pharmacokinetics were performed on day 1 of course 1 (all patients) and course 2 (only patients receiving intravenous topotecan on that day). In course 1, urine and feces were collected for up to 9 days after the first dosage. The amounts of topotecan and N-desmethyl topotecan in plasma, urine and feces were determined by validated high-performance liquid chromatographic assays. RESULTS: A total of 11 patients were enrolled in the study. Nine patients were evaluable for pharmacokinetics. Plasma pharmacokinetics were similar to those previously reported. The principal route of excretion was the urine, with approximately 49% of the intravenously administered topotecan dose and 20% of the oral dose collected in the urine as parent drug. Approximately 18% and 33% of the intravenous and oral dose, respectively, were recovered unchanged in the feces. Only small amounts of N-desmethyl topotecan were found in the excreta. CONCLUSIONS: Fecal and urinary excretion of unchanged topotecan were the major routes of topotecan elimination. Approximately 28% of the intravenous dose and 43% of the oral dose of topotecan were unaccounted for and eliminated through other routes.

Administration, Oral↗

PubMed2002

Population pharmacokinetics of the novel anticancer agent KRN7000.

PURPOSE: KRN7000 is a novel anticancer agent, acting through stimulation of the immune system. The first clinical trial with this agent, which included pharmacokinetic studies, has recently been completed. The aim of the study presented here was to develop a population pharmacokinetic model for KRN7000. METHODS: Plasma concentration-time data were gathered from 24 patients enrolled in a phase I trial in which KRN7000 was administered as a weekly slow injection at doses ranging from 50 to 4800 microg/m(2). These data were used to build a pharmacokinetic model using the nonlinear mixed-effect modeling (NONMEM) program. The model was validated by performance of 200 bootstraps. RESULTS: A three-compartment model with interindividual variability on the central and two peripheral volumes of distribution (V1, V2 and V3) and on clearance (CL) adequately described the data. The final estimates were: V1 2.34 l, V2 2.61 l, V3 2.13 l, and CL 0.130 l/h. Of 24 covariates tested, including both demographic and pathophysiological factors, none showed a significant relationship with the pharmacokinetic parameters obtained. The bootstrap analysis provided parameter estimates within approximately 15% of the original estimates, indicating stability of the model. CONCLUSION: The pharmacokinetic behavior of KRN7000 in the clinical trial could be described by a three-compartment model. Hence, KRN7000 demonstrates linear pharmacokinetics over the investigated dose range. The pharmacokinetics of KRN7000 are not influenced by patient demographic or pathophysiological characteristics.

Adult↗

PubMed2002

Population pharmacokinetic and adverse event analysis of topotecan in patients with solid tumors.

OBJECTIVE: Our objective was to describe the pharmacokinetics and pharmacodynamics of topotecan in patients. METHODS: Data were pooled from 9 clinical trials. Topotecan, as a single-agent therapy, was administered as a daily 30-minute intravenous infusion for 5 days on a 3-week cycle. Doses of 0.2 to 2.0 mg/m(2) were studied; concentration and neutropenic event data were obtained on multiple occasions. The pharmacokinetics were characterized with use of hierarchical nonlinear regression. The relationship between severity of neutropenia and exposure was characterized with use of logistic regression. RESULTS: The pharmacokinetics of topotecan were described with a linear 2-compartment model. Compromised renal function, low body weight, and poor Eastern Cooperative Oncology Group performance status were determinants of lower clearance, resulting in elevated exposure. Application of covariates reduced interpatient variability in clearance. Logistic regression showed that topotecan area under the concentration-time curve from 0 to 24 hours was predictive of the severity of neutropenia; the only other significant covariate was the number of courses of previous treatment with platinum-based regimens. CONCLUSIONS: Patients with compromised renal function, low body weight, or poor performance status had low topotecan clearance. Patients with high topotecan AUC had an increased probability of experiencing severe neutropenia, which was greater if the patient had been pretreated with platinum-based agents. The use of covariates to individualize dose would result in less variability in exposure, reducing the likelihood of severe neutropenia and potentially improving treatment benefit.

Adult↗

PubMed2002

Clinical pharmacology of the novel marine-derived anticancer agent Ecteinascidin 743 administered as a 1- and 3-h infusion in a phase I study.

Ecteinascidin 743 (ET-743) is an anticancer agent derived from the Caribbean tunicate Ecteinascidia turbinata. In the present article, the pharmacokinetics and pharmacodynamics of ET-743 are described within a phase I study. Forty patients with solid tumors initially received ET-743 as a 1-h i.v. infusion every 21 days at nine dose levels (50-1100 microg/m(2)). The maximal tolerated dose (MTD) was 1100 microg/m(2), with thrombocytopenia and fatigue as dose-limiting toxicities (DLTs). As this MTD was substantially lower than in parallel phase I studies, dose escalation continued using a prolonged, 3-h infusion. Thirty-two patients were entered at five dose levels (1000-1800 microg/m(2)). The MTD was 1800 microg/m(2) with pancytopenia and fatigue as DLTs. The recommended phase II dose was 1650 microg/m(2) given over 3 h at which 12 patients were treated. Pharmacokinetic monitoring was performed for both treatment schedules. Non-compartmental pharmacokinetic parameters at the recommended dose with the 3-h infusion were (mean value+/-SD): clearance 87+/-30 l/h and mean elimination half-life 26+/-7 h. Pharmacokinetics were linear at the dose range tested with this schedule. The percentage decrease in platelets, white blood cells and neutrophils correlated with the area under the plasma concentration versus time curve (AUC), dose and maximal plasma concentration (C(max)). Hepatic toxicity increased with dose, AUC and C(max). Administration of 1650 microg/m(2) ET-743 over 3 h seemed clinically feasible; pharmacokinetics were linear with this schedule. Hepatic and hematological toxicities correlated with exposure to ET-743.

Adult↗

PubMed2002

An excretion balance and pharmacokinetic study of the novel anticancer agent E7070 in cancer patients.

E7070 is a novel sulfonamide anticancer agent that arrests the G /S phase of the cell cycle. Preclinical and phase I studies have demonstrated non-linear pharmacokinetics of the drug. The objective of this study was to quantify the excretion of E7070 and the metabolite 1,4-benzene-sulfonamide (M1) in cancer patients. E7070 (1,000 mg) radiolabeled by (14)C in the benzene disulfonamide moiety (cohort 1, n = 6) or in the indole moiety (cohort 2, n = 7) was i.v. infused over 1 h. The levels of radioactivity in plasma, red blood cells, urine and feces were determined by liquid scintillation counting, and the E7070 and M1 concentrations in plasma, urine and feces were determined by coupled liquid chromatography-tandem mass spectrometry (LC/ESI-MS/MS). In plasma, the mean area under the concentration-time curve (AUC) based on radio-activity measurements (32.5 and 28.9 h. mM in cohorts 1 and 2, respectively) was substantially higher than the mean AUC of E7070 (3.8 h x mmol/l) and M1 (0.1 h x mmol/l) in all patients. The excretion of radioactivity (mean +/- SD) as a percentage of administered radioactivity was higher in urine [63.7 +/- 9.8% (cohort 1) and 61.5 +/- 5.5% (cohort 2)] than in feces [22.7 +/- 2.6% (1) and 21.1 +/- 3.1% (2)] during a mean collection period of 11 days. In both cohorts, the contribution of urinary and fecal recovery of E7070 (2.3 and 2.7%, respectively) and M1 (5.3 and 5.1%, respectively) was low. Subsequent HPLC analysis with online radioisotope detection of urine showed that the high radioactivity levels are caused by compounds other than E7070 and M1. The major metabolite is formed by glucuronidation of a hydroxylated metabolite of E7070. In conclusion, the excretion of the benzene sulfonamide and the indole moieties of E7070 was the same with a higher renal than gastrointestinal excretion. E7070 is extensively converted into currently unidentified metabolites. Glucuronidation is a major metabolic pathway.

Adult↗

PubMed2002

A phase I and pharmacokinetic study of ecteinascidin-743 on a daily x 5 schedule in patients with solid malignancies.

PURPOSE: The purpose of this study was to (a) assess the feasibility of administering ecteinascidin-743 (ET-743), a novel DNA minor-groove disrupting agent of marine origin, administered as a daily i.v. infusion for 5 days every 3 weeks; (b) recommend a dose for Phase II studies; (c) characterize its pharmacokinetic behavior; and (d) seek preliminary evidence of anticancer activity. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were treated with escalating doses of ET-743 as a daily 1-h i.v. infusion for 5 days every 3 weeks. Plasma and urine were sampled on both days 1 and 5 of the first course. Pharmacokinetic parameters were related to the principal toxicities. RESULTS: Forty-two patients were treated with 118 courses of ET-743 at doses ranging from 6 to 380 microg/m(2)/day. Elevations in hepatic transaminases were common at ET-743 dose levels > or =216 microg/m(2)/day, resolved rapidly, and were never dose limiting nor cumulative. Instead, hematological toxicity was the principal toxicity that precluded dose escalation. The maximum tolerated dose of ET-743 that could be administered repetitively was 325 microg/m(2)/day. Antitumor activity was noted in three patients with leiomyosarcoma and primary peritoneal and ovarian carcinomas. The pharmacokinetics of ET-743 were dose independent, and drug accumulation over the 5 days of treatment was modest, with the ratio of the area under the plasma-versus-time curve on day 5 to that on day 1 averaging 2.05. The volume of distribution at steady state was large (mean, 1037 liters/m(2)), and the mean terminal half life on day 5 was 26.81 h. CONCLUSIONS: The maximum tolerated dose of ET-743 that can be administered repetitively is 325 microg/m(2)/day daily x 5 every 3 weeks, which is recommended for disease-directed clinical trials. The acceptable toxicity profile of ET-743 on the divided-dose schedule evaluated in this trial, as well as the generally superior antitumor activity associated with divided-dose schedules in preclinical studies, provides a rationale for further evaluation of ET-743 on this administration schedule.

Adult↗

PubMedDate not supplied

Liquid chromatography-mass spectrometry for the quantitative bioanalysis of anticancer drugs.

The monitoring of anticancer drugs in biological fluids and tissues is important during both pre-clinical and clinical development and often in routine clinical use. Traditionally, liquid chromatography (LC) in combination with ultraviolet (UV), fluorescence, or electrochemical detection is employed for this purpose. The successful hyphenation of LC and mass spectrometry (MS), however, has dramatically changed this. MS detection provides better sensitivity and selectivity than UV detection and, in addition, is applicable to a significantly larger group of compounds than fluorescence or electrochemical detection. Therefore, LC-MS has now become the method of first choice for the quantitative bioanalysis of many anticancer agents. There are still, however, a lot of new developments to be expected in this area, such as the introduction of more sensitive and robust mass spectrometers, high-throughput analyses, and further optimization of the coupled LC systems. Many articles have appeared in this field in recent years and are reviewed here. We conclude that LC-MS is an extremely powerful tool for the quantitative analysis of anticancer drugs in biological samples.

Animals↗