Epic Sciences, Inc. (Epic) announces that it will present data, in conjunction with Endocyte, Inc., comparing its proprietary single cell CTC analysis to PSMA targeted imaging in mCRPC patients to provide insight into disease heterogeneity and identify potential therapeutic resistance mechanisms.
In the study to be presented, “PSMA heterogeneity analysis in patients with metastatic castrate-resistant prostate cancer (mCRPC): Imaging versus CTCs (Poster#207307),” 96 samples taken prior to treatment and throughout therapy from 40 mCRPC patients were compared for PSMA expression by imaging using Endocyte’s proprietary targeted imaging agent (99mTc-EC0652) vs. Epic’s CTC analysis. Almost all patients were scored positive for tumor PSMA expression by imaging, and although CTCs were observed in 88% of patients, only 43% of these patients showed CTCs expressing PSMA. Within patient samples, single cell analysis showed that PSMA expression was heterogeneous from cell to cell demonstrating the complexity of target expression. Additional CTC biomarker analysis identified markers associated with resistance to standard of care therapies in significant portions of patients, including AR-V7 (28%), HRD (38%), high tumor cell heterogeneity (22%) and NEPC (9%).
Epic Sciences has previously published the clinical impact of these markers on standard of care therapeutic response in mCRPC, AR targeted therapies or Taxane chemotherapy. “The discordance of PSMA expression in the active metastatic portion of the tumor burden (CTCs) along with the presence of multiple significant markers of therapeutic resistance demonstrate the degree of heterogeneity often observed in this patient population and the need to characterize these resistance mechanisms subclonally prior to and throughout the course of treatment,” said Mark Landers, vice president of translational research at Epic Sciences.
Dr. Alison Armour, chief medical officer at Endocyte, commented, “This biological heterogeneity was a consideration in Endocyte’s new strategy to target PSMA expression with 177Lu-PSMA-617 as surrounding PSMA negative cells, within the pathlength of the beta emission, could still be irradiated with a ‘bystander effect.'”
About Epic Sciences
Epic Sciences, Inc. is developing novel diagnostics to personalize and advance the treatment and management of cancer. Epic Sciences’ mission is to enable the rapid and non-invasive detection of genetic and molecular changes in cancer throughout a patient’s journey. The company was founded on a powerful platform to identify and characterize rare cells, including circulating tumor cells. Epic Sciences No Cell Left Behind® technology helps match patients to therapies and monitor for drug resistance so that the best treatment path can be chosen at every clinical decision point. Epic Sciences has partnered with Genomic Health to commercialize the Oncotype DX® AR-V7 Nucleus DetectTM test, which helps with therapeutic decisions between taxane chemotherapy or androgen-directed therapeutics in metastatic castrate-resistant prostate cancer. Today, we partner with leading pharmaceutical companies and major cancer centers around the world. Epic Sciences’ goal is to increase the success rate of cancer drugs in clinical trials and improve patient outcomes by providing physicians real-time information to guide treatment choices. Epic Sciences is headquartered in San Diego.