The biliary clearance (Cl(biliary)) of three compounds was estimated using sandwich-cultured human hepatocytes (SCHH) and compared with Cl(biliary) values measured in vivo. Tc-99m sestamibi (MIBI) Cl(biliary) was determined in seven healthy volunteers using an oroenteric catheter to aspirate duodenal secretions, and gamma scintigraphy to determine gallbladder contraction; this technique was used previously to determine Tc-99m mebrofenin (MEB) and piperacillin (PIP) in vivo Cl(biliary). In vitro Cl(biliary) of MEB, MIBI, and PIP was quantified in SCHH as the ratio of mass excreted into bile canaliculi and area under the blood concentration-time curve (AUC) in medium. MIBI Cl(biliary) in vivo was 5.5+/-1.2 mL/min/kg (mean+/-SD). The rank order of Cl(biliary) predicted from SCHH corresponded well with the in vivo Cl(biliary) values in mL/min/kg for MEB (7.44 vs 16.1), MIBI (1.20 vs 5.51), and PIP (0.028 vs 0.032). In conclusion, the methods developed allowed for reproducible quantification of Cl(biliary) of drugs in healthy humans and prediction of Cl(biliary) from in vitro data.
Ispinesib (SB-715992) inhibits the mitotic kinesin spindle protein (KSP), a novel target for anticancer therapy. A phase II study was conducted to examine the efficacy of ispinesib in recurrent or metastatic head and neck squamous cell carcinoma (RMHNSC). Patients with up to one prior line of chemotherapy for RMHNSC were treated with ispinesib 18 mg/m2 IV over 1 hour every 21 days. Twenty-one patients were enrolled onto this study with a target stage I sample size of 19. Of 20 evaluable patients, no objective responses were seen and stable disease > 2 cycles was observed in five patients (25%). The median time to progression was 1.4 (95% CI 1.3-2.3) months, median survival was 3.5 (95% CI 2.8-7.8) months, and 1 year overall survival was 20% (95% CI 8.3-48.1%). The most frequent attributable grades III-V adverse events were neutropenia (60% of patients) and leukopenia (55%). The pharmacokinetic profile was consistent with results from phase I studies. Archival tissues (n = 14) demonstrated low to moderate KSP expression by immunohistochemistry. In addition, no pharmacodynamic changes were observed in peripheral blood mononuclear cells. We detected no antitumor activity of ispinesib in RMHNSC on this dosing schedule.
The aim of this study is to define the maximum tolerated dose (MTD), safety, pharmacokinetics (PKs) and efficacy of ispinesib (SB-715992) in combination with docetaxel. Patients with advanced solid tumours were treated with ispinesib (6 -12 mg m À2 ) and docetaxel (50 -75 mg m À2 ). Docetaxel was administered over 1 h followed by a 1-h infusion of ispinesib on day 1 of a 21-day schedule. At least three patients were treated at each dose level. Blood samples were collected during cycle 1 for PK analysis. Clinical response assessments were performed every two cycles using RECIST guidelines. Twenty-four patients were treated at four dose levels. Prolonged neutropaenia and febrile neutropaenia were dose limiting in six and two patients, respectively. The MTD was ispinesib 10 mg m À2 with docetaxel 60 mg m À2 . Pharmacokinetic assessment demonstrated concentrations of ispinesib and docetaxel, consistent with published data from single agent studies of the drugs. Seven patients (six hormone refractory prostate cancer (HRPC), one renal cancer) had a best response of stable disease (X18 weeks). One patient with HRPC had a confirmed 450% prostatic-specific antigen decrease. The MTD for ispinesib and docetaxel was defined and the combination demonstrated an acceptable toxicity profile. Preliminary PK data suggest no interaction between ispinesib and docetaxel.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.