Evaluation of the antineoplastic activity of mitoxantrone–l-carnitine combination therapy on an experimental solid form of ehrlich tumour in mice

We have commenced a series of experiments to evaluate the effect of carnitine derivatives on the antineoplastic activity of mitoxantrone (MX) on various animal cancers. This report describes the therapeutic effect of MX in combination with l-carnitine (LCAR) on the growth of a solid form of Ehrlich tumour inoculated into mice. LCAR was administered subcutaneously at doses of either 200 or 100 mg kg−1 on day 6 and 13 after tumour inoculation, 1 h prior to the treatment with MX. Mitoxantrone was administered intravenously at doses of 3 or 6 mg kg−1. We found that LCAR had no potentiating effect on the efficacy of MX, in terms of either slowing tumour growth or increasing the survival of mice. Nevertheless, therapeutic effects can be assumed at higher doses of both drugs based on values calculated from an index of relative hazards.