Weekly oral paclitaxel as first-line treatment in patients with advanced gastric cancer.
BACKGROUND
Pharmacokinetic study has shown that co-administration of cyclosporin A (CsA), which acts as a P-glycoprotein (P-gp) and CYP-3A blocker, resulted in an 8-fold increase in the systemic exposure of oral paclitaxel. Two doses of oral paclitaxel on 1 day in combination with CsA resulted in higher systemic exposure than single dose administration.


METHODS
In this phase II study, chemonaïve patients with advanced gastric cancer received oral paclitaxel weekly in two doses of 90 mg/m(2) on the same day; CsA (10 mg/kg) was given 30 min before each dose of oral paclitaxel.


RESULTS
In 25 patients, the main toxicities were: nausea CTC grade 2/3, 10 patients (40%); vomiting grade 2/3, 4 patients (20%); diarrhea grade 2/3, 6 patients (24%); neutropenia grade 3/4, 5 patients (20%). In the 24 evaluable patients, eight partial responses were observed, resulting in an overall response rate (ORR) of 33% [95% confidence interval (CI) 18% to 52%]. Eleven patients had stable disease (46%) and 5 patients showed progressive disease (21%). The ORR in the total population was 32% (95% CI 17% to 50%). The median time to progression was 16 weeks (95% CI 9-22). Pharmacokinetic analyses revealed that the mean area under the plasma concentration-time curve (AUC) of orally administered paclitaxel (+/- standard deviation) was 3757.6 +/- 939.4 ng.h/ml in week 1 and 3928.4 +/- 1281 ng.h/ml in week 2. The intrapatient variability in the AUC was 12%.


CONCLUSIONS
Oral paclitaxel in combination with CsA is both active and safe in chemonaïve patients with advanced gastric cancer. Toxicities were mainly gastrointestinal.
Kruijtzer
C M F
CM
The Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
Boot
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Beijnen
J H
JH
Lochs
H L
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Parnis
F X
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Planting
A S T
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Pelgrims
J M G
JM
Williams
R
R
Mathôt
R A A
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Rosing
H
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Schot
M E
ME
Van Tinteren
H
H
Schellens
J H M
JH
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology; D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology*; D003131:Combined Modality Therapy; D016572:Cyclosporine / Q000008:administration & dosage* / Q000494:pharmacology; D003967:Diarrhea / Q000139:chemically induced; D004334:Drug Administration Schedule; D004791:Enzyme Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000139:chemically induced; D017239:Paclitaxel / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology*; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000473:pathology; D016896:Treatment Outcome; D014839:Vomiting / Q000139:chemically induced
D000972:Antineoplastic Agents, Phytogenic; D004791:Enzyme Inhibitors; D016572:Cyclosporine; D017239:Paclitaxel