Bioavailability of etoposide after oral administration of the solution marketed for intravenous use: therapeutic and pharmacoeconomic perspectives.

BACKGROUND: Oral etoposide administration is a suitable alternative to the intravenous route; therefore, commercial capsules have been developed. Before these capsules were available in Mexico, we studied drug bioavailability after oral administration of the intravenous etoposide solution (IVES). METHODS: Eight adult cancer patients received a 50-mg oral etoposide dose as IVES and blood samples were collected over a period of 24 h. Plasma etoposide concentration was determined by high-performance liquid chromatography, plasma concentration against time curves were constructed, and bioavailability parameters were calculated. RESULTS: Oral IVES yielded an adequate bioavailability profile because Cmax was 2.38 +/- 0.30 micrograms/mL, AUC was 12.87 +/- 2.02 micrograms/mL and half-life was 6.72 +/- 0.97 h. CONCLUSIONS: Considering that the pharmacokinetic aim is to maintain plasma concentrations between 0.5 and 1.0 microgram/mL for several hours while avoiding high concentrations, i.e., of 10 micrograms/mL or higher, oral administration of 50-mg etoposide as IVES appears to be a suitable dosing option. In addition, oral IVES is considerably less expensive than intravenous administration in terms of both drug presentation and administration.

Cetuximab concomitant with gemcitabine and radiotherapy in advanced squamous cell carcinomas of upper aerodigestive tract: a pilot study

PURPOSE: To explore the response and toxicity of advanced non-metastatic squamous cell carcinomas of upper aerodigestive tract (SCC-UADT) to a combination of cetuximab concomitant with gemcitabine and radiotherapy. METHODS: We managed patients with concomitant treatment of cetuximab (400 mg/m(2) as uploading dose, then 250 mg/m(2), IV) concomitant with gemcitabine (50 mg/m(2)) weekly for seven courses, and radiotherapy in classical fractionation until completion of 70 Gy. Primary endpoints were complete response (CR) to treatment and toxicity. We evaluated patients for toxicity on a weekly basis; evaluation of response included physical examination, endoscopy, computed tomography (CT) scan and biopsy when indicated, and was performed 6 weeks after completion of radiotherapy. Additional evaluations were done every 3 months to document disease status. Between November 2004 and November 2005, 20 patients were included. RESULTS: CR was 82.4%, overall response was 100%. Neck disease reached CR in 61.5% and partial in 38.5% of patients. The main toxicities were nausea, lymphopenia, neutropenia and mucositis. Grade 3 and 4 side effects were presented in 70.6% of patients, but mucositis, and lymphopenia without clinical repercussions, occurred in 88.2% of patients. Gastrostomy was required in 11.8% of patients to maintain nutrition. Radioepithelitis developed in 76.5%, but only three of these (23.1%) were grade III. Median overall survival was 53 months (range 6-55 months) and median progression-free survival has not yet been reached at the time of evaluation. CONCLUSIONS: Although toxicity is important, this approach has interesting activity and deserves further investigation (AU)