Lorus identifies novel class of lead drug candidates from small molecule anticancer program

Aug 24 2005

Lorus Therapeutics has announced the continued success in the development of its small molecule anticancer program with the selection of a sub-class of lead molecules from the Company's small molecule program. Two molecules from this sub-class, ML-133 and LT-253, have been chosen as lead candidates for further development as novel anticancer drugs, based on the results of preclinical studies.

ML-133 and LT-253 are part of the ML-series, which is a group of novel low molecular weight compounds that shows significant anti-proliferative activity against many human cancer cell lines. In the in vitro anticancer screening program of the U.S. National Cancer Institute (NCI), which includes 60 human cancer cell lines representing nine cancer types, ML-133 exhibited potent activity against colon carcinoma, leukemia, non-small cell lung cancer, and prostate cancer cell lines.

Because of its activity against several cancer types as well as its novel mechanism of action, the NCI selected ML-133 for testing in the Hollow Fiber Assay to assess in vivo anticancer activity and systemic availability. This makes ML-133 one of a small percentage of compounds selected by the NCI for testing in this assay. In the Hollow Fiber Assay, ML-133 demonstrated antitumor efficacy towards several human cancers. LT-253, which is related in chemical structure to ML-133, has also shown promising antitumor activity in vivo. Like ML-133, LT-253 demonstrates potent growth inhibition in xenograft models of various human cancers, including colon carcinoma and non-small cell lung cancer.

Lorus and collaborators at the University of Toronto are currently in the process of developing formulations of ML-133 and LT-253 to characterize pharmacokinetic properties. The goal of these studies is to advance drug candidates into clinical trials as quickly as possible.

"We are excited about the continued success of our small molecule anticancer program. It is Lorus' strategy to develop a broad diversified technology base in the cancer area, for the benefit of cancer patients, to add further value to Lorus' drug development program, and to mitigate risks inherent in the drug development process. The antitumor properties of ML-133 and LT-253 contribute significantly to this strategy."