Small molecule lead drug candidate blocks a critical target for tumors and crosses the blood brain barrier; begins first brain cancer patient dosing in clinical trial at MD Anderson Cancer Center
In the ongoing challenge to combat the almost always deadly brain cancers, namely Glioblastoma and melanoma metastasized to the brain, the pharmaceutical company Moleculin Biotech, Inc., (Nasdaq: MBRX) has initiated a Phase 1 clinical trial of a new first-in-class cancer drug candidate, a small molecule compound discovered by Prof. Waldemar Priebe at The University of Texas MD Anderson Cancer Center and known as WP1066. The compound has been shown in animal models to both inhibit an important cell signaling protein STAT3 that is involved in cell growth and proliferation and considered critical to tumor development, while also stimulating an immune response. The first glioblastoma patient has received the initial doses of WP1066, which were apparently well tolerated, in the physician-sponsored IND (investigational new drug) study at MD Anderson Cancer Center.
Built from the chemical backbone of the active ingredient in propolis, a natural product of honey bees, WP1066 is the first anticancer agent with drug-like properties that consistently inhibits the activated form of STAT3 within cancer cells, a target that has been long-sought because of its broad range of tumor promoting effects.
Importantly, activated STAT3 supports the survival and proliferation of tumor cells, evasion of the immune response and metastasis to distant organs, as well as angiogenesis (growth of blood vessels) essential for tumor growth. Activated STAT3 is not only connected with directly supporting tumor activity, but also suppressing the immune system, making this target even more important to cancer therapy.
With the support of extensive preclinical studies demonstrating high antitumor activity and the critically important ability to cross the blood-brain barrier, WP1066 in this Phase 1 clinical trial will focus on treating aggressive brain tumors which all share a grim prognosis. The intent is to eventually treat up to 15 relapsed brain cancer patients over the next six to eight months. Phase 1 clinical trials typically focus on exploring safe and well tolerated doses, as well as evaluating initial signals of effectiveness. Each treatment is completed over three weeks.
“Treating the first brain tumor patient with WP1066 is the start of a very exciting and encouraging program for doctors treating the worst types of brain cancers. There has been very little progress in recent years toward improved therapies for glioblastoma and other aggressive primary or metastatic brain tumors. WP1066 has shown extremely promising results based on animal studies where we have seen inhibition of tumor growth and improvements in survival,” said Dr. Sandra Silberman, a world-renowned oncologist and Moleculin’s Chief Medical Officer. “This is based on the fact that although STAT3 has long been identified as an important target for treating tumors, for years most efforts have focused on attempts to indirectly inhibit STAT3 from upstream signaling, not from within the cancer cell itself. WP1066 appears to be unique in its ability in vitro and in animal models to consistently and directly inhibit the activated form of STAT3 and produce significant anticancer effects, including tumor growth inhibition and increased life span of treated animals.”
“This represents a major milestone for Moleculin,” commented Walter Klemp, Chairman and CEO. “There has been tremendous enthusiasm within the oncology community for targeting STAT3, a key molecular hub of multiple pathways promoting tumor growth. Although the industry has been struggling to find a way to target STAT3, we at Moleculin believe that most of these efforts have been mechanistically misguided and ended in failure because their approach would ultimately be ineffective at adequately blocking the activation of STAT3 and lack the necessary drug-like properties to succeed. The opportunity to test a unique STAT3 therapy in these patients is significant in supporting Moleculin’s mission to provide benefit for those who need new and better treatments.”
