Tessera Inc., a Seattle-based biomedical company is, in collaboration with Dr. Robert Getzenberg, Director of the Brady Urological Research Institute at Johns Hopkins University, developing blood tests for both prostate and colon cancer and expects to commence clinical trials on EPCA (Early Prostate Cancer Antigen), its first blood test for prostate cancer, before the end of this year.
Dr. Getzenberg's initial study on the EPCA prostate cancer blood test has been published in the May 15, 2005 issue of Cancer Research. In the study, the EPCA protein was measured in the plasma of 46 individuals, including prostate cancer patients, healthy individuals, other cancer patients, spinal cord injury victims and patients with prostatitis. Sensitivity of the EPCA assay for prostate cancer patients was 92% while the overall specificity was 94%. Specificity for the healthy donors was 100%.
"This new blood test (EPCA), when coupled with PSA screening, may help reduce the number of unnecessary biopsies and undetected prostate tumors," said Getzenberg. "In addition to being highly sensitive to prostate cancer, the EPCA blood test is also very specific to it, meaning that other cancers and benign prostate conditions are not detected, thus boosting doctors' confidence that a positive EPCA test is really a sign of prostate cancer," added Getzenberg.
Multi-site clinical trials will soon be underway to verify EPCA's usefulness for detecting prostate cancer in a larger sample of patients in preparation for an FDA clearance submission.
According to Dr. Getzenberg, "Our ultimate objective is to differentiate between aggressive and non-aggressive forms of prostate and colon cancer. Through our collaboration with Tessera over the past three years, we are making significant progress toward the achievement of this important goal."
Six weeks ago Tessera announced the release of its first product, EPCA IHC, for use in pathology labs on tissue samples taken in prostate biopsies, as an aid in detecting cancer in biopsy samples which otherwise appear to be normal. EPCA IHC was also developed in collaboration with Dr. Getzenberg. Tessera expects to launch a similar pathology test for colon cancer within the next year.