Lorus Therapeutics Inc. announced that its Phase I clinical study of LOR-253 has successfully escalated to the target dose level based on predicted and observed clinical effects without limitation by toxicity. The success of this study allows Lorus to initiate a biomarker clinical investigation to further explore the effects of the drug at relevant doses determined in the clinical trial. This Phase I clinical study program, conducted at Memorial Sloan Kettering Cancer Center in New York and the MD Anderson Cancer Center in Houston, has enrolled 27 patients in escalating doses who had advanced or metastatic solid tumors that were unresponsive to conventional therapy or for which no effective therapy is available.

The drug has shown excellent safety characteristics since it has safely escalated to more than 10-fold the starting dose. Further information on the safety, pharmacokinetic and anticancer properties of LOR-253 will be reported in a future scientific congress following audited analysis of the data. The biomarker study will enroll 10 patients eligible for pre- and on-treatment biopsies who have specific cancers prioritized for further clinical development of LOR-253.

Lorus anticipates the further analysis and reporting of the biomarker findings in the second half of the year. The intratumoral biomarker evaluations in the biomarker study will include the KLF4 target of LOR-253. KLF4 is believed to play an important tumor suppressor function in the cell, which is depressed in major cancers but expected to be restored or upregulated by the action of LOR-253.

Non-small cell lung and colorectal cancers have shown excellent KLF4 target-related activity in previous studies and are priority indications for the biomarker study. The company expects the biomarker study to provide insights into the relationship of intratumoral and circulating cancer biomarkers to indicators of treatment benefit or response now that the relevant target dose level has been reached.