Immunicon (Huntingdon Valley, Pennsylvania) is a company on the move on more than one front.

And company CEO Byron Hewett is on top of all of it, particularly with last week’s news that the company met its primary endpoint associated with its pivotal trial in metastatic-androgen independent prostate cancer.

That good news goes hand-in-hand with its current clearances in metastatic breast cancer, as well as positive results reported in September on its pivotal trial in colorectal cancer.

“We’re very excited about the fact that our assay works across three major carcinomas,” Hewett told Medical Device Daily. “These three cancers account for around 600,000 newly diagnosed cases of cancer each year in the U.S. This is a big market opportunity, so this [would be] a big thing for us to broaden our claim into other carcinomas.”

Specifically, Hewett was referring to the pivotal study of its CellSearch Circulating Tumor Cell Kit. The Cell Search System, which the company said is the first diagnostic technology to automatically identify and count CTCs in a tube of blood. The system is marketed in the field of cell analysis in cancer by Veridex (Raritan, New Jersey), a business of Johnson & Johnson (New Brunswick, New Jersey).

The primary endpoint for the study was that circulating tumor cells (CTC) levels three-to-five weeks after the initiation of chemotherapy would predict overall survival. The study also showed that CTC levels predict overall survival at each of the tested times, the company said.

The prospective, multi-center trial using the kit is designed for longitudinal enumeration of CTCs in patients with metastatic androgen-independent prostate carcinomas about to start either their first or later line of chemotherapy.

Between October 2004 and February 2006, 276 patients were enrolled in the trial at 65 sites in the U.S. and Europe. The company said that all patients had whole-body bone scans performed prior to therapy, and those with measurable disease had CT scans of the abdomen and pelvis performed prior to the initiation of therapy and at subsequent intervals following institutional guidelines.

All patients had serum samples collected for prostate-specific antigen measurements at baseline and at about monthly intervals thereafter. CTCs were also measured at baseline and at about monthly intervals thereafter using CellTracks technology.

Patients remained in the study up to 18 months or until evidence of disease progression and/or death, whichever occurred first.

Leon Terstappen, MD, PhD, senior VP and chief scientific officer of Immunicon, said, “We are pleased that the data in prostate cancer are consistent with those in breast and colorectal cancer and broaden the clinical utility of our products.”

Terstappen said the company expects to submit the data to the FDA and for scientific presentations and publications later this year.

In September, the company reported that it met its primary and secondary endpoints in its pivotal trial in colorectal cancer. The primary endpoint was that the number of CTCs 3 to 5 weeks after the initiation of therapy would agree with a patient’s response to therapy as determined by imaging 6 to 12 weeks after initiation of therapy.

In December, the company received monitoring claims for metastatic breast cancer (Medical Device Daily, Dec. 26, 2007).

Hewett said the company received its first claims from the FDA and launched products in August 2004 related to metastatic breast cancer. The claim stated that “five or more circulating tumor cells predict a shorter progression-free and overall survival for patients” with metastatic breast cancer.

An article in the New England Journal of Medicine also reported on those claims.

Hewitt said: “Some of the physicians’ comment was, ‘Gee, OK, you’re going to tell me who’s going to die earlier and who’s going to live longer, but how do I really use this to manage my patients?’”

After more analysis of the initial data, the company found that women with five or more cells at baseline, who also had five or more CTCs in subsequent blood draws, had a median survival of 4.1 months. That compares to women who started with the same number of cells at baseline but dropped, as they showed a median survival of 19.8 months.

“A 15-month survival benefit in response to therapy is reflected by a reduction in cell county,” Hewett said. “So that additional information was allowed into our package insert by the FDA in late October of 2005.”

That brings the total to three clearances in metastatic breast cancer for the company.

In November of last year, Immunicon reported that Clinical Cancer Research published a study in which principal author, G. Thomas Budd, MD, of the Cleveland Clinic Foundation (Cleveland), concluded: “Asessment of CTCs is an earlier, more reproducible indication of disease status than current imaging methods. CTCs may be a superior surrogate endpoint, as they are highly reproducible and correlate better with overall survival than do changes determined by traditional radiology.”

Currently, CT scans are used as the standard of care to assess therapy effectiveness, the company said.

In addition to the studies that the company is conducting in oncology, Immunicon in recent months has entered agreements with a handful of drug companies, including Pfizer (New York) and AstraZeneca (London), to help those companies develop drugs that can be paired with diagnostics to determine how efficacious or toxic they might be to specific patients.

“The concept here is to look at the expression of either certain proteins or genes in the circulating cells that are associated with that particular targeted therapy,” Hewett said.

The agreement with Pfizer was extended and expanded last March, based on Immunicon’s development of an assay to be used with a targeted therapy based on a particular receptor.

What Pfizer found was that in those patients that are positive to a specific receptor on their circulating cells, “almost 60% of those patients responded to therapy, whereas those patients that were negative for that particular receptor, only about 15% responded.”

That finding prompted Pfizer to expand the relationship with Immunicon, he said.

Immunicon also reported an agreement in December with Diagnostic Hybrids (Athens, Ohio), which will move the company beyond the oncology arena into the development of infectious disease assays, something the company had outlined as part of its strategy for 2006 and beyond.