Phase I clinical evaluation of carboplatin in tumor-bearing cats: a Veterinary Cooperative Oncology Group study.
BACKGROUND
The dosage of carboplatin in cats has been reported anecdotally and experimentally in non-tumor-bearing cats, but the dosage for carboplatin treatment in tumor-bearing cats has yet to be defined in a prospective clinical trial.


OBJECTIVE
To determine the maximally tolerated dose (MTD) and dose-limiting toxicosis (DLT) of carboplatin in tumor-bearing cats. CATS: Fifty-nine cats with measurable solid tumors.


METHODS
The starting dose of carboplatin was 160 mg/m(2) of body surface area IV. Doses were increased by 20 mg/m(2) in cohorts of 3-14 cats until the MTD was reached.


RESULTS
The 59 cats entered into this multi-institutional phase I study received 1 or more doses of carboplatin at various dosages and were evaluated for toxicity, response to treatment, or both. The MTD was 240 mg/m(2) and neutropenia was the DLT. For the 1st cycle of treatment in 44 cats evaluated for neutropenia, 6 episodes of grade 3 or greater neutropenia occurred on days 7 (n=1), 14 (n=4), and 21 (n=1). There was no evidence of drug-induced nephrotoxicosis or pulmonary edema. Preliminary evidence of antitumor activity was observed in 7 of 59 (11.9%; 95% CI, 5.6-22.8%) cats evaluated for response to treatment. There was 1 complete response (cutaneous hemangiosarcoma) and 6 partial responses (4 injection site sarcomas, 1 oral squamous cell carcinoma, 1 lymphoma). Responses were of short duration (median, 42 days; range, 7-168 days).


CONCLUSIONS
The dose of carboplatin recommended to treat tumor-bearing cats is 240 mg/m(2) IV every 3-4 weeks.
Kisseberth
W C
WC
Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA. kisseberth.2@osu.edu
Vail
D M
DM
Yaissle
J
J
Jeglum
K A
KA
Couto
C G
CG
Ward
H
H
Khanna
C
C
Obradovich
J E
JE
D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D016190:Carboplatin / Q000009:adverse effects / Q000627:therapeutic use*; D002371:Cat Diseases / Q000139:chemically induced / Q000188:drug therapy*; D002415:Cats; D003404:Creatinine / Q000097:blood; D004305:Dose-Response Relationship, Drug; D005260:Female; D007674:Kidney Diseases / Q000139:chemically induced / Q000662:veterinary; D008297:Male; D009369:Neoplasms / Q000188:drug therapy / Q000662:veterinary*; D009503:Neutropenia / Q000139:chemically induced / Q000662:veterinary; D013921:Thrombocytopenia / Q000139:chemically induced / Q000662:veterinary
D000970:Antineoplastic Agents; D003404:Creatinine; D016190:Carboplatin