Phoenix Molecular Designs 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.”