Efficacy, safety and pharmacokinetics of palonosetron in patients receiving highly emetogenic cisplatin-based chemotherapy: a dose-ranging clinical study.

BACKGROUND: Although currently available 5-hydroxytryptamine type 3 receptor (5-HT3) antagonists are effective, not all patients receiving these agents achieve adequate control of chemotherapy-induced nausea and vomiting (CINV). Palonosetron, a potent and highly selective 5-HT3 antagonist with a strong affinity for 5-HT3 and a prolonged plasma elimination half-life, may provide a longer duration of action than other approved agents. PATIENTS AND METHODS: One hundred and sixty-one patients were randomly assigned to receive a single intravenous bolus dose of palonosetron (0.3, 1, 3, 10, 30 or 90 microg/kg) before administration of highly emetogenic chemotherapy, with no pretreatment with corticosteroids. RESULTS: The four highest doses of palonosetron were similarly effective during the first 24 h, producing clearly higher complete response (CR) (no emesis, no rescue medication) rates in the 3, 10, 30 and 90 microg/kg groups (46%, 40%, 50% and 46%, respectively) than in the 0.3-1 microg/kg group (24%) of evaluable patients (n = 148). The 3 microg/kg dose was identified as the lowest effective dose. A single dose of palonosetron showed prolonged efficacy in preventing delayed emesis, with approximately one-third of patients who received palonosetron 10 or 30 microg/kg maintaining a CR throughout the 7-day period following chemotherapy administration. Dose-proportional increases in pharmacokinetic parameters and a long plasma half-life (43.7-128 h) were observed. Palonosetron was well-tolerated, with no dose-response effect evident for the incidence or intensity of adverse events. CONCLUSIONS: Palonosetron is an effective and well-tolerated agent for the prevention of CINV following highly emetogenic chemotherapy, with 3 and 10 microg/kg identified as the lowest effective palonosetron doses.

Pseudomembranous colitis leading to toxic megacolon associated with antineoplastic chemotherapy. Report of a case and review of the literature.

Pseudomembranous colitis and toxic megacolon are rare complications of antineoplastic chemotherapy. Twelve cases of pseudomembranous colitis and four cases of toxic megacolon, both occurring as complications of chemotherapy, have been reported in the medical literature. These diseases occurred as separate and distinct entities. Fulminating pseudomembranous colitis leading to toxic megacolon in the setting of chemotherapy has not been previously reported. We report such a case, emphasizing its atypical presentation and rapid, fulminant course.

Detection of the hemoglobin E mutation using the color complementation assay: application to complex genotyping.

The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine-labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population.