Phase I trial of piroxicam in 62 dogs bearing naturally occurring tumors.
Piroxicam, a nonsteroidal antiinflammatory drug, was given to 62 dogs bearing naturally occurring tumors in a phase I clinical trial. Dose escalation was performed, with oral doses ranging from 0.5 mg/kg every 48 h (q48h) to 1.5 mg/kg q48h being tested. Dose-limiting gastrointestinal irritation/ulceration occurred in all four animals that received 1.5 mg/kg q48h. The maximum tolerated dose was 1 mg/kg q48h. Subclinical renal papillary necrosis occurred in two dogs (initial dosages, 1 and 1.5 mg/kg q48h, respectively). Following dose escalation, an additional group of dogs was treated with 0.3 mg/kg piroxicam q24h per os, the accepted canine dosage prior to this trial. Inclusion of this treatment group enabled evaluation of the toxicity of and tumor response to a daily dosage regimen. No complete remissions occurred in this trial. Partial remission was documented in three of ten dogs exhibiting transitional-cell carcinoma, in three of five animals bearing squamous-cell carcinoma, in one of three dogs displaying mammary adenocarcinoma, and in the one dog that exhibited a transmissible venereal tumor. The results of this study support the additional evaluation of piroxicam in a phase II clinical trial in dogs bearing naturally occurring tumors.
Knapp
D W
DW
Purdue Comparative Oncology Program, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.
Richardson
R C
RC
Bottoms
G D
GD
Teclaw
R
R
Chan
T C
TC
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D004283:Dog Diseases / Q000188:drug therapy* / Q000473:pathology; D004285:Dogs; D004334:Drug Administration Schedule; D004341:Drug Evaluation; D005260:Female; D008297:Male; D009369:Neoplasms / Q000662:veterinary*; D010894:Piroxicam / Q000009:adverse effects / Q000097:blood / Q000627:therapeutic use*
D000970:Antineoplastic Agents; D010894:Piroxicam