Platinum Analogue Combination Chemotherapy: Cisplatin and Carboplatin-A Phase I Trial With Pharmacokinetic Assessment of the Effect of Cisplatin Administration on Carboplatin Excretion

Cisplatin (NSC 119875) and carboplatin (NSC 241240) are platinum (II) analogues with very different spectra of toxicity. Cisplatin dose is limited by nausea and vomiting, renal dysfunction, and dose-related peripheral neuropathy, whereas carboplatin is myelosuppressive. There are also clinical and laboratory data that suggest that these drugs may not be completely cross-resistant. Therefore, the following phase I trial of combination therapy with cisplatin and carboplatin was undertaken. Since carboplatin toxicity is enhanced in the presence of renal impairment, carboplatin excretion was also evaluated in selected patients at the maximum tolerated dose. Thirty-three patients received 50 mg/m2 cisplatin and doses of carboplatin between 160 mg/m2 and 400 mg/m2. Sequential 20-minute infusions of carboplatin and then cisplatin were able to be administered at the standard doses of carboplatin (320 and 400 mg/m2) with thrombocytopenia to the degree expected if carboplatin alone had been given. However, 280 mg/m...