Mersana Therapeutics, a platform-based cancer therapeutics company, announced today that a review of the Company's lead compound, XMT-1001, will appear in the November 12, 2009 special issue of Advanced Drug Delivery Reviews on Polymer Therapeutics: Clinical Applications and Challenges for Development. The review article, entitled, "XMT-1001, a novel polymeric camptothecin pro-drug in clinical development for patients with advanced cancer," was authored by Alexander V. Yurkovetskiy, Ph.D., and Robert J. Fram, M.D., both of Mersana, and provided an overview of XMT-1001 in the context of other topoisomerase I inhibitors conjugated to polymers or encapsulated in liposomes.
XMT-1001 is a conjugate of the broad-spectrum cytotoxic camptothecin (CPT) that employs Mersana's Fleximer® platform. XMT-1001 is currently in a Phase 1 trial in patients with advanced solid tumors. Non-Fleximer-linked CPT was shown to be active in prior clinical studies conducted by the National Cancer Institute (NCI), but was discontinued due to severe bladder toxicity. The XMT-1001 program significantly improves on the clinically active drug, providing broad-spectrum activity with potentially better efficacy and safety.
According to the review, XMT-1001 demonstrated an improved therapeutic window compared to CPT or irinotecan in human tumor xenograft studies. The review also reports that XMT-1001, unlike many other conjugated CPT analogs, provides a slow and sustained systemic release of well defined drug products, enabling drug delivery to tumor, both in low molecular weight and in macromolecular forms. This dual-release mechanism of XMT-1001 may result in lower levels of CPT in the urine and less bladder toxicity, a serious dose-limiting toxicity associated with CPT and CPT conjugated to other polymers.