Almac Diagnostics said this week that a group led by partner Precision Therapeutics has independently validated Almac's ColDx test for stage II colorectal cancer recurrence ahead of its full commercialization in the US.
Almac Diagnostics, a division of the Craigavon, UK-based Almac Group, developed the test using Affymetrix's GeneChip platform, and has licensed the test to Pittsburgh-based Precision to market and sell in the US under the name GeneFx Colon.
ColDx is a 634-probe gene expression signature that can be used to differentiate patients as having higher versus lower risk of recurrence within five years following surgery. The test is performed on formalin-fixed, paraffin-embedded samples extracted from patients during surgery.
Michael Sloan, vice president of business development for Almac Diagnostics, told BioArray News this week that Precision has already introduced ColDx via its CLIA-compliant laboratory in a "limited initial release to top academic institutions in the US," and that GeneFx Colon "will become broadly available later this year."
To support the roll out of GeneFx Colon, Precision undertook a validation study of the test in cooperation with partners from the Alliance for Clinical Trials in Oncology, which consists of researchers from Duke University, Dana-Farber Cancer Institute, the University of Chicago, and other institutions. Precision and investigators from the alliance presented their findings from this validation study at the 2014 Gastrointestinal Cancers Symposium, held earlier this month in San Francisco.
Almac and partners had already published a study of ColDx in 2011 that showed its validation in a set of 144 samples, where it identified high-risk patients with an hazard ratio of 2.53 for recurrence and an HR of 2.21 for cancer-related death. This newer, external study relied on data and samples from 393 stage II colon cancer patients enrolled in an alliance clinical trial to assess the ability of the prognostic to stratify patients based on their risk of colorectal cancer recurrence.
According to a statement, the ColDx signature "remained significant after adjustment for conventional prognostic risk factors ... including micro-satellite instability, T-stage, and number of nodes examined."
Sloan said that the new external validation study is "highly significant" for Almac and Precision. "This second independent validation of ColDx has been carried out in the Precision Therapeutics lab and shows that the signature is valid, and that the technology transfer from Almac to Precision Therapeutics has been successful," he said.
Precision offers a number of tests to aid clinicians in treating cancer patients, including Rosetta Genomics' microarray-based Cancer Origin Test. Precision and Rosetta also co-market Rosetta's array-based miRview Mets 2 test in the US.
While Precision is Almac's partner for ColDx in the US, the company is looking for other partners to make the signature available to clinicians in Europe and elsewhere.
"Colon cancer is a serious burden worldwide and the potential patient benefit that can be offered from the test is significant," said Sloan. "As such we are keen to bring the test to market in more countries and are exploring and evaluating a range of options to do so."
In addition to its ColDx signature, Almac has a pipeline of oncology-based tests in development in therapeutic areas including breast, colon, ovarian, prostate, and lung cancer. Another Almac assay that can be used to gauge a breast cancer patient's response to chemotherapy has been licensed to Genomic Health. Unlike that test, though, which has been transferred to an RT-PCR-based platform, the ColDx test will continue to be offered on an Affymetrix-made microarray, Sloan said.