Allos Therapeutics has reported data from an ongoing, multicenter, Phase I dose-escalation study of the anticancer agent RH1.

In the study, patients with advanced solid tumors refractory to other chemotherapy regimens are being administered increasing doses of RH1. RH1 is being administered as a 10- to 30-minute intravenous infusion on Day 1 and 5, every three weeks for up to six cycles.

RH1 is a small molecule chemotherapeutic agent that is bioactivated by the enzyme DT-diaphorase, or DTD, which is over-expressed in many tumors relative to normal tissue, including lung, colon, breast and liver tumors. The bioactivated form is a potent cytotoxic agent that induces DNA inter-strand cross-linking. Because RH1 is bioactivated in the presence of DTD, it has the potential to provide targeted drug delivery to these tumor types while limiting the toxicity to normal tissue.