Background: The antitumor efficacy of the combination of Nedaplatin (NDP) with cyclophosphamide (CPM) was evaluated using murine and human carcinoma implanted mice. NDP was developed as a second generation platinum complex. Because of its superior antitumor activity and lower nephrotoxicity than Cisplatin (CDDP), we also compared the antitumor activity of NDP plus CPM with that of CDDP plus CPM.
Materials and methods: Various doses of NDP or CDDP (1/4 to 1 maximum tolerated dose; MTD) and CPM (58 or 78 mg/kg) were injected once via the tail vein into mice implanted with Lewis murine lung carcinoma or Ma44 human lung carcinoma.
Results: Simultaneous administration of NDP or CDDP with CPM resulted in synergistically enhanced inhibition of tumor growth and prolonged survival in comparison with therapy using only NDP, CDDP or CPM. The combination therapy of NDP with CPM showed a superior survival effect with frequent long-term tumor-free survivors in comparison to that of CDDP plus CPM without increased hematotoxicity. The augmented antitumor efficacy of the combination of NDP with CPM was also demonstrated against Ma44 human lung carcinoma.
Conclusion: The results suggested the effectiveness of using a combination of NDP with CPM for clinical therapy.