Phase I and II agents in cancer therapy: two cisplatin analogues and high-dose cisplatin in hypertonic saline or with thiosulfate protection.

Cisplatin is a chemotherapeutic coordination complex that has been evaluated extensively. It is particularly active against testicular cancer, but carcinomas of the ovary, bladder, cervix, and head and neck are also responsive. To increase efficacy and decrease toxicity, a number of platinum analogues have been developed and tested. One of these, carboplatin, is of particular interest. In clinical trials, it has demonstrated antitumor activity comparable to that of cisplatin, without evidence of significant renal toxicity or neurotoxicity. A second interesting platinum analogue is iproplatin. Preliminary phase I studies suggest reduced adverse renal and neurologic effects similar to those seen with carboplatin, with efficacy comparable to cisplatin. Attempts to overcome the dose-limiting toxicity of cisplatin by administering high-dose cisplatin (40 mg/m2/d for five days) in hypertonic saline or with thiosulfate protection are also reviewed. These techniques have eliminated nephrotoxicity as the dose-limiting toxicity of cisplatin. However, nonrenal toxicity, especially neurotoxicity, remains substantial. The extent to which high-dose cisplatin-based chemotherapy should be used in routine clinical practice has not been determined.