Laboratory Corporation of America last week announced that it has entered into a license agreement with Veridex, a unit of Johnson and Johnson, to commercialize a diagnostic that may give doctors more confidence in diagnosing patients with prostate cancer.
Although the terms of the agreement were not disclosed, the deal with Veridex allows LabCorp to strengthen its position in the oncology diagnostics market, particularly within prostate cancer.
The reference lab giant already has a leading presence in the space thanks to its 2003 acquisition of Dianon Systems and its second-generation prostate-specific antigen test. Additionally, LabCorp’s customer base is strongly focused on prostate cancer.
“We are one of the largest providers of cancer diagnostics through pathology. Prostate cancer has certainly been a long standing interest of ours,” Myla Lai-Goldman, executive vice president, chief scientific officer, and medical director for LabCorp, told Pharmacogenomics Reporter this week. “This is an area in which we have an interest and a large client base.”
Veridex’s test, based on nucleic acid testing technology, detects for the presence of methylated GST-Pi, “a key tissue marker in prostate cancer,” according to a LabCorp statement.
Current methods for diagnosing prostate cancer combine PSA testing and biopsy, but such methods don’t always provide a complete picture regarding a patient’s disease status. “Many patients are suspected to have prostate cancer through their PSA test and go in for biopsy. But the biopsy doesn’t give all the information that is really needed,” Lai-Goldman said.
“The biopsy may not show cancer, but the PSA, which is the blood test, makes the doctor strongly suspicious that cancer is present. With that, the doctor then has the decision to make as to whether to go back [to] re-biopsy the patient immediately or to watch and wait,” she said.
According to the National Cancer Institute’s estimates, in 2006 there will be more than 230,000 new cases of prostate cancer and more than 27,000 will die from the disease.
Researchers have identified that DNA hypermethylation, a common epigenetic change that occurs in prostate cancer, has a hand in silencing the expression of the GST-Pi gene.
“When utilized in combination with conventional histopathology testing, an assay quantifying the level of methylated GST-Pi may provide a more sensitive and accurate detection of prostate cancer than histology alone,” LabCorp said in a statement.
According to the company, the test would be used in patients who have had biopsies with “suspicious histopathology” and elevated PSA values with biopsy results that come back negative.
Veridex’s technology, which is slated for launch before the end of the year, would allow doctors to glean more information from the biopsy sample.
“That would give the physician more indication as to what the next step would be,” Lai-Goldman said. The test “goes beyond PSA and routine tissue biopsy and gets more information [that] may assist the physician in waiting more comfortably in not having to go in immediately and having to re-biopsy the patient.”
LabCorp plans to market the test using its existing sales force. Reps will target and educate urologists.
“Our marketing is through educating our physician customers … in terms of clinical utility of the test, in conjunction with the information from the published literature,” Lai-Goldman said. “So our approach is generally an educational one.”
The test “goes beyond PSA and routine tissue biopsy and gets more information and this may assist the physician in waiting more comfortably in not having to go in immediately and having to re-biopsy the patient.”
According to Steven Anderson, vice president and chief scientific officer of molecular diagnostics at LabCorp, the specificity of methylated GST-Pi as a marker for prostate cancer is well established in published literature.
“This is a rapidly developing field, but if you look at where the applications are most mature, where there is the strongest support in the literature right now, prostate cancer and GST-Pi ranks up as one of the most well studied and supported in the literature as markers,” Anderson told Pharmacogenomics Reporter this week.
In a review article published in the Jan. 19, 2005, issue of the Journal of the National Cancer Institute, “Epigenetic Changes in Prostate Cancer: Implication for Diagnosis and Treatment,” authorsreported that in one study methylated GST-Pi detection in urine after prostatic massage was able to detect prostate cancer with a specificity of 98 percent and an overall sensitivity of 73 percent. However, another study that investigated post-biopsy urine samples, researchers found that the specificity and sensitivity of the marker was lower, 67 percent and 58 percent, respectively.
“Specificity and sensitivity were even lower if simple voided urine was used as the DNA source,” the authors note.
Still, the authors concluded in the Journal of the National Cancer Institute review article that although “ample evidence suggests that DNA methylation detection can serve as a promising tumor biomarker … in the prostate, only the [GST-Pi] gene shows sufficient specificity and sensitivity in detecting prostate cancer to warrant further testing as a tumor marker in patients’ body fluids such as serum, urine, and ejaculate.”
According to LabCorp, while there are other tests detecting GST-Pi for prostate cancer being used by academic scientists in a research setting. Veridex’s product is poised to be the first such test to be commercialized. The company said it is the first company to license the Veridex test.
DiagnoCure markets a PCA3 diagnostic test for prostate cancer. In addition, DeCode Genetics has discussed plans to develop and launch diagnostics that will test chromosome 8q markers for prostate cancer. In April, Illumina announced that scientists from the National Cancer Institute identified a new polymorphism correlated to prostate cancer using its Infinium HumanHap300 and HumanHap240S BeadChips.