-Diagnostic can detect activated RSK2, a prime target in TNBC, in breast cancer patients-
VANCOUVER, British Columbia and SAN DIEGO, Jan. 16, 2019 /PRNewswire/ — Phoenix Molecular Designs (PhoenixMD), a privately-held biotechnology company designing precise cancer therapeutics by targeting essential kinases, announced that it has entered into a collaboration with Roche to develop a diagnostic (CDx) in triple-negative breast cancer (TNBC). The Roche CDx identifies RSK2 activation in human tumors. In cancer, the PDK-1 and MAPK pathways converge on RSK2 to activate it, moving it from the cytoplasm into the nucleus. Measuring nuclear RSK2 signifies activation and abundance of this emerging drug target.
Complementing its diagnostic efforts, PhoenixMD has also developed PMD-026, which is the first orally available small molecule inhibitor that targets RSK2, a prime drug target in multiple cancers. The leading focus for PhoenixMD is in the treatment of triple-negative breast cancer (TNBC) given the companies’ core expertise in developing breast cancer therapeutics.
The diagnostic assay developed through the Roche/PhoenixMD collaboration will relay information on how active the RSK2 pathway is in TNBC and other cancers. Preliminary data indicates that 80 percent of cases (52/65 TNBC cases) express activated RSK2. More broadly, researchers have investigated more than 300 biopsies and found that RSK2 is activated in 65 percent of tumors from a study of 13 different tumor types. RSK2 was also detected in breast cancer metastases using this method. Over the coming months, Roche will establish a CAP/CLIA certified protocol as a gateway into clinical tumor analyses. In upcoming clinical trials, PhoenixMD will further refine the precision of the RSK2 CDx in identifying patients that may ultimately benefit from PMD-026. In the near term, PhoenixMD expects to file an IND for PMD-026 and initiate a Phase I/Ib study in women with TNBC.
“By working together, PhoenixMD and Roche are at the forefront of innovation in TNBC, the most deadly breast cancer type with no approved therapies. Creating our diagnostic assay and identifying disease biomarkers, such as RSK2 for TNBC, will dramatically reduce the development time needed to create targeted drugs and will improve a drug’s chance of advancing through clinical trials,” said Dr. Sandra E. Dunn, CEO of PhoenixMD. “The top-line data generated from our CDx is encouraging, and we look forward to applying these learnings to identify TNBC patients that may benefit from PMD-026 in our upcoming Phase I/Ib study.”
About Triple Negative Breast Cancer (TNBC) and RSK Kinases
Approximately 400,000 cases of TNBC are diagnosed every year worldwide and it is one of the most difficult breast cancer subtypes to treat due to lack of effective, targeted therapies. TNBC also claims the lives of young women more than any other type of breast cancer due to a lack of understanding around the therapeutic bullseye. It is also a very heterogeneous disease, therefore a common denominator across TNBC types was necessary to identify the bullseye. Through genome-wide screens, RSK was identified as the prime target for TNBC by scientists at PhoenixMD. Currently, there are no approved targeted therapies available for TNBC.
There are four types of RSK involved in cancer, known as RSK1-4, and each type has a unique role in the development of the disease. RSK1 is responsible for cancer cell invasion and is an important driver in the spread of cancer. RSK2 controls cancer cell growth, and RSK3 and RSK4 are associated with drug resistance.
RSK1 and RSK2 have been proven critical to the survival of patients with TNBC. Over 90 percent of primary TNBC cases express high levels of RSK1 and RSK2. Inhibiting RSK2 eliminates TNBC cells completely, including cancer stem cells, which give rise to cancer recurrence. PhoenixMD, with its novel, targeted approach, is focused on creating patented cancer RSK inhibitors and companion diagnostics for cancer indications – initially in breast cancer – with the potential to treat blood, brain, ovarian, lung, skin, prostate, colon, head and neck cancers.
While there are currently no approved targeted therapies for TNBC, several drugs are involved in research studies and clinical trials. PhoenixMD is addressing this unmet medical need through a novel, targeted approach by inhibiting critical kinases, such as RSK1-4, a group of highly conserved Ser/Thr kinases that promote cell proliferation, growth, motility and survival. For this target, PhoenixMD developed PMD-026, a first-in-class, specific RSK inhibitor that blocks downstream signaling of RSK and induces apoptosis.
PhoenixMD is a privately-held biopharmaceutical company designing precise cancer therapeutics and companion diagnostics by targeting kinases, a class of highly druggable enzymes to treat a wide range of oncology indications. PhoenixMD is focused on developing first-in-class inhibitors against ribosomal S6 kinase (RSK), an important drug target for cancer, heart disease, and inflammation. Due to its emerging leadership in kinase inhibition, PhoenixMD has entered into partnerships with well-recognized academic, non-profit institutions and development companies such as the National Cancer Institute (NIH), University of Florida, Kyushu University, Mayo Clinic and University of HawaiiComprehensive Cancer Center. PhoenixMD is headquartered in Vancouver, British Columbia Canada, with U.S. operations in San Diego, Calif. For more information, visit phoenixmd.ca.