Pharmacokinetics of Lonidamine after oral administration in cancer patients.

The pharmacokinetics of Lonidamine has been studied in cancer patients after single and chronic oral administrations. After single administration the plasma kinetics are highly variable, while the dose eliminated in the urine is over 70% in all subjects. This suggests an active but interindividually variable first-pass effect. After repeated administrations, both the residual plasma concentration before administration (C infinity min) and that obtained after drug intake (C infinity max) have been studied. The C infinity max values range from 4.5 to 25 micrograms/ml and C infinity min values from 0.4 to 7 micrograms/ml. In patients where a therapeutic response was noted, a mean value of 2.98 micrograms/ml for C infinity min was measured. In patients unresponsive to drug therapy the mean C infinity min was 1.5 micrograms/ml.