Protracted dosing of the lipophilic camptothecin analogue AR-67 in non-small cell lung cancer xenografts and humans.

Purpose Although preclinical studies on camptothecin antitumor effect have demonstrated the superiority of low-dose protracted dosing, these findings were not replicated in the clinic. 7-t-butyldimethylsilyl-10-hydroxycamptothecin (AR-67) is a camptothecin analogue currently under investigation in early phase clinical trials. To maximize the therapeutic potential of AR-67, we sought to identify factors that affect response to treatment.