Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The discovery and development of the taxoid class of antitumor compounds, most notably paclitaxel, originally extracted from the Pacific yew, and its semisynthetic analog docetaxel, represent significant advances in the treatment of patients with a variety of malignancies. Although paclitaxel and docetaxel have a similar chemical root, extensive research and clinical experience indicate that important biological and clinical differences exist between the two compounds. Although the mechanism by which they disrupt mitosis and cell replication is novel and unique to this class of compounds, there are small but important differences in the formation of the stable, nonfunctional microtubule bundles and in the affinity of the two compounds for binding sites. These differences may explain the lack of complete cross-resistance observed between docetaxel and paclitaxel in preclinical and clinical studies. The two taxoids also exhibit slightly different toxicity and clinical efficacy profiles. Docetaxel-induced adverse events have been shown to occur most frequently in patients with impaired liver function, and a reduction in dosage in patients with raised levels of transaminases and alkaline phosphatase is recommended to improve the tolerability of the drug in these patients. The incidence and severity of problematic adverse effects such as hypersensitivity, skin reactions, and a cumulative fluid retention syndrome are minimized with the routine administration of a 3- to 5-day corticosteroid-based premedication regimen with each docetaxel infusion. The results of ongoing studies of taxoid-based monotherapies and combination regimens will further optimize the benefits achievable with these drugs, and new preclinical findings also may lead to new clinical uses for these and future drugs of the taxoid class.
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PMID:The taxoids: same roots, different drugs. 933 11

Docetaxel has been reported to show promising anti-tumour activity in pancreatic ductal cancer (PC). This study was conducted to evaluate the activity and toxicity of moderate-dose (60 mg m(-2)) docetaxel in Japanese chemo-naive patients with measurable metastatic PC. The patients had a performance status of 0-2. They received docetaxel intravenously over a 1- to 2-h period without any premedication for hypersensitivity reactions. This treatment was repeated every 3-4 weeks with dose adjustments based on the toxic effects observed. Twenty-one patients were eligible and treated with docetaxel. The median number of courses was 2 (range, 1-4). None of the patients achieved an objective response; seven showed no change and 13 showed progressive disease. In one patient, the response was not assessable because of early death. The median survival time for all patients was 118 days. The main grade 3-4 toxicities by patient were leucocytopenia (67%) and neutropenia (86%). Other grade 3-4 toxicities included anaemia (10%), thrombocytopenia (5%), nausea/vomiting (29%), anorexia (29%), GOT/GPT increase (10%), alkaline phosphatase increase (14%), malaise/fatigue (33%) and alopecia (24%). In conclusion, docetaxel, administered on this schedule, did not show significant anti-tumour activity in patients with metastatic PC.
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PMID:Phase II study of docetaxel in patients with metastatic pancreatic cancer: a Japanese cooperative study. Cooperative Group of Docetaxel for Pancreatic Cancer in Japan. 1040 50

Docetaxel, a taxane antitumor agent, was administered to 24 patients by a 1-h intravenous infusion at a dose level of 100 mg/m(2) with pharmacokinetic monitoring. The plasma concentration-versus-time data were fitted with a three-compartment model. The mean area under the curve (AUC) for docetaxel was 3.1 +/- 0.9 h. mg/l and the clearance was 34.8 +/- 9.3 l/h per m(2). There was considerable interpatient pharmacokinetic variability. In 33% of the patient population, metabolites were detected in plasma samples collected 5-30 min after the end of the infusion. The cyclized oxazolidinedione metabolite M4 was most frequently present and was detected in 8 out of 24 patients with maximal concentrations between 0.022 and 0.23 mg/l. Logistic regression analysis was performed to predict M4 docetaxel metabolism. In the final model, alanine aminotransferase and alkaline phosphatase levels were the strongest predictors. No relationship was found between M4 metabolism and percentage decrease in neutrophil count in this study. Three patients with high M4 concentrations in plasma during course 1 suffered from most pronounced fluid retention (grade 2-3) after two to five courses.
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PMID:Pharmacokinetics and metabolism of docetaxel administered as a 1-h intravenous infusion. 1066 39

Docetaxel is a chemotherapeutic agent effective in the treatment of various solid tumors. Patients given a standard dose of docetaxel exhibit wide interpatient variation in clearance (CL) and toxic effects. Docetaxel undergoes metabolism by cytochrome CYP3A4. Thus, interpatient variability in CYP3A4 activity may account in part for differences in toxicity and CL. Twenty-one heavily pretreated patients with metastatic sarcomas received docetaxel (100 mg/m2). Hepatic CYP3A4 activity in each patient was measured by the [14C-N-methyl]erythromycin breath test (ERMBT). Blood samples were taken at selected times over the next 24 h for pharmacokinetic analysis. Phenotypic expression of hepatic CYP3A4 activity measured by the ERMBT varied over 20-fold (administered 14C exhaled in 1 h: mean, 2.53%; range, 0.25-5.35%), which is similar to a normal control population. CL of docetaxel varied nearly 6-fold (mean, 21.0 liters/h/m2; range, 5.4-29.1 liters/h/m2). The ERMBT was the best predictor of CL when compared with serum alanine aminotransferase, albumin, alkaline phosphatase, or serum alpha-1-acidic glycoprotein. The natural log of ERMBT accounted for 67% of the interpatient variation in CL. Multivariate analysis showed that the natural log of ERMBT and albumin together accounted for 72% of the interpatient variation in CL. The greatest toxicity was seen in patients with the lowest ERMBT. Hepatic CYP3A4 activity is the strongest predictor of docetaxel CL and accounts for the majority of interpatient differences in CL. Patients with low CYP3A4 activity are at risk for having decreased CL and may thus experience increased toxicity from docetaxel. Those with high activity may be receiving a suboptimal dose. By measuring CYP3A4 activity, the ERMBT may be clinically useful in tailoring doses of CYP3A4 substrates, such as docetaxel, in certain individuals.
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PMID:The effect of an individual's cytochrome CYP3A4 activity on docetaxel clearance. 1077 42

The population approach has been implemented prospectively in the clinical development of docetaxel (Taxotere). Overall 640 patients were evaluable for the population PK/PD analysis. The PK analysis evidenced significant covariates explaining the inter-patient variability of docetaxel clearance and the PK/PD analysis demonstrated that the variability in clearance was a significant predictor of several safety endpoints. In patients with clinical chemistry suggestive of mild to moderate liver function impairment (SGOT and/or SGPT > 1.5 x ULN concomitant with alkaline phosphatase >2.5 x ULN), total body clearance was lowered by an average of 27%. Specific safety analyses demonstrated that these patients are at a significantly higher risk than others for the development of severe docetaxel-induced side effects. Population PK/PD data were fully integrated into the regulatory dossier and in the labeling of docetaxel worldwide. Population PK/PD models are being used to elaborate a simulation model to predict the survival of patients with non-small cell lung cancer treated with docetaxel.
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PMID:Population pharmacokinetics and pharmacokinetic-pharmacodynamic relationships for docetaxel. 1139 50