Medical Device Daily

Genoptix (Carlsbad, California), a provider of personalized medicine oncology services, has become only the second major national laboratory to offer the CellSearch System, which it said is the only FDA-cleared test designed to identify circulating tumor cells (CTCs) in patients with metastatic breast cancer to offer physicians insight into the prognosis for such patients.

CellSearch is a diagnostic platform commercially available from Veridex (Warren, New Jersey), a Johnson & Johnson (New Brunswick, New Jersey) company. In September 2004, Quest Diagnostics (Lyndhurst, New Jersey) became the first national laboratory to offer the test (Medical Device Daily, Sept. 21, 2004).

“CellSearch is an important diagnostic tool designed to help oncologists and their patients fight cancer,“ said Tina Nova, president and CEO of Genoptix. “The system's analysis of circulating tumor cells in the blood provides valuable insight into cancer regression and progression that oncologists can use to develop personalized treatment strategies for individual patients.“

The CellSearch test “identifies counts of circulating tumor cells in the blood of metastatic breast cancer patients,“ Susan Bailey, vice president, marketing at Genoptix, told Medical Device Daily. Circulating tumor cells are present in the blood when a primary cancer sheds tumor cells into the circulatory system.

“There is a direct correlation between the number of cells and [patients'] progression-free survival time to overall survival time,“ she said.

Counts below five CTCs are considered “favorable,“ meaning patients will have a longer progression-free survival and a longer overall survival time than patients who have more than five CTCs. Genoptix said that CellSearch is capable of detecting as low as one CTC in 7.5 milliliters of whole blood, and with a high specificity at five or more CTCs, it “virtually eliminates false positives.“

Bailey said that the company was approached by Veridex to begin offering the test, “because they were very intrigued by the fact that we have a sales force that is dedicated exclusively to oncology.“

“So, we had the opportunity to provide them with physicians that would be interested in the test through our existing client base,“ Bailey said, noting that Genoptix serves “community hematologists/oncologists.“

Genoptix also has the Veridex instrument required to conduct the CellSearch test, in addition to using the required kit. But, she said, the instrument is “costly and usually requires a certain volume of testing to make it economically feasible except for a large group practice or a hospital to purchase the instrument.“

There are a number of academic centers, including National Cancer Institute (NCI; Bethesda, Maryland) facilities that currently provide the test, such as M.D. Anderson Cancer Cancer (Houston). However, a patient would be required to have access to a particular large center or be treated by a physician affiliated with that center.

“This then provides Veridex with an opportunity to provide the test to smaller community physicians that would have need for it through our sales force,“ she said, noting the Genoptix sales force is “nationwide.“

Bailey said she expects the interest and response from such community hematologists and oncologists to be “very positive“ as they compare CellSearch with some of the other tools they may be using to monitor metastatic breast cancer patients.

“It is another endpoint for them - and a very specific endpoint - to look at in terms of response to treatment or efficacy of treatment - so, the overall survival of these patients and what can be done for their quality of life,“ she told MDD.

For example, a fall in CTC levels after a new therapy is begun would suggest an appropriate response to therapy, Genoptix said.

“Early information about changes in CTCs may help physicians evaluate the effectiveness of therapy much earlier than using conventional radiologic methods,“ said Mike Nerenberg, MD, Genoptix vice president of medical affairs. “In the future, this may become the preferred method for deciding when to change therapy, thus avoiding unnecessary side effects that are caused by ineffective therapy.“

Veridex received clearance from the FDA in January 2004 for the CellSearch Epithelial Cell Kit to be used for the enumeration of circulating tumor cells of epithelial origin in whole blood.

Results of a prospective, multicenter study published Aug. 19 in the New England Journal of Medicine demonstrated that the number of circulating tumor cells is predictive of progression-free survival and overall survival in metastatic breast cancer patients (MDD, Sept. 21, 2004).

MDD first reported on Genoptix in July 2004, when the company reported that it had received its clinical laboratory license from the California Department of Health Services to offer “CLIA-compliant, high-complexity medical testing services for certain blood and lymph system cancers“ (MDD, July 15, 2004). Nova said the company had raised by $35 million up to that point. The company raised an additional $17 million in August of last year (MDD, Aug. 11, 2005).

Nova said then that the funds would help the company “accelerate expansion of our sales and marketing team, add capacity to our laboratory and grow our revenues.“

In speaking with MDD on Thursday, Bailey said, “At this point in time, to the best of my knowledge, we have no plans on seeking additional funds, because we are at a point where we are on track to break even, and we are generating revenue.“