Prometheus Laboratories Inc, a specialty pharmaceutical and diagnostic company, presented an overview of its proprietary oncology diagnostic platform yesterday at the American Society of Clinical Oncology (ASCO) Annual Meeting in Orlando, Fla.

In a presentation entitled "Profiling of Receptor Tyrosine Kinases (RTK) Activation in Circulating Tumor Cells (CTCs) in Metastatic Tumors Using Proximity Mediated Microarray Immunoassay," Prometheus demonstrated that its novel microarray platform can successfully detect the activation of key cancer pathways EGFR and HER2 in CTCs isolated from blood samples of patients with high specificity and sensitivity as high as a single cell.

Testing of samples from frozen breast cancer tissues demonstrated concordance between reported HER2 status based on immunohistochemistry (IHC), a commonly used biopsy-based method, and the Prometheus diagnostic platform. Further, an analysis of CTCs from metastatic breast cancer patients showed that more than 50% of patients with HER2 negative primary tumors had CTCs with activated HER2 and approximately 30% of these patients had both activated and amplified HER2 over time. A copy of the presentation can be found on the Company’s Web site.

"As our understanding of molecular targets and cancer pathways increases, so too does our need for sophisticated diagnostics," said Henry Pan, MD, PhD, Chief Scientific and Medical Officer of Prometheus. "We believe the sensitivity and specificity of our proprietary diagnostics may help oncologists to optimize the choice of a growing number of targeted therapies for breast, lung, colorectal and other cancers. In addition, we believe the ability to isolate CTCs from whole blood and fine needle aspirates will be less invasive than current methods of biopsy and enable real-time, continuous monitoring of patients post-treatment."

Prometheus is currently implementing multiple studies in a clinical setting with an initial focus on metastatic breast cancer. The Company submitted an application for New York State approval in the first quarter of 2009 and anticipates the commercial launch of its first oncology diagnostic product thereafter upon completion of selected ongoing clinical studies.

New Product Names for MicroRNA-based Diagnostics

Prometheus also unveiled new product names at ASCO for three recently introduced microRNA-based diagnostics:

  • ProOnc TumorSource Dx (sold as miRview(™) mets outside the U.S.), a test designed to accurately identify the primary tumor site in patients with metastatic cancer;
  • ProOnc Squamous Dx (sold as miRview(™) squamous outside the U.S.), a test to differentiate squamous from non-squamous non-small cell lung cancer; and
  • ProOnc Mesothelioma Dx (sold as miRview™ meso outside the U.S.), a test to differentiate mesothelioma, a cancer connected to asbestos exposure, from other carcinomas in the lung and pleura.

The Company acquired exclusive US rights to the three tests from Rosetta Genomics in April 2009.

Source: Prometheus Laboratories Inc