Antitumor activity of a new platinum compound (glycolate-o,o') diammineplatinum (II) (254-S), against non-small cell lung carcinoma grown in a human tumor clonogenic assay system.

(Glycolate-o,o') diammineplatinum (II) (254-S) is one of the platinum derivatives showing high activity against rodent solid tumors and lack of renal toxicity. We have used a human tumor clonogenic assay (HTCA) as a disease-oriented drug screening model for new antitumor drugs, in order to test the antitumor activity of 254-S against non-small cell lung carcinoma (NSCLC) and to compare its activity with that of cisplatin (CDDP) and of carboplatin (CBDCA). The overall in vitro response rate (defined as less than 50% survival of tumor colony forming units) for 254-S was observed in 10/29 and 20/30 evaluable specimens isolated freshly from NSCLC patients with continuous exposure at 1 and 10 micrograms/ml, respectively, indicating a positive dose-response relationship. Dose dependent cytotoxicity was also confirmed in 4 human tumor cell lines derived from NSCLC patients. The antitumor activity of 254-S was 3.6-fold that of CBDCA, but two-fifths that of CDDP. A comparison of these in vitro results with the toxic properties of 254-S such as low nephrotoxicity suggests that 254-S is a promising new drug against NSCLC.