Life sciences companies are gearing up for battle to capture the profitable prostate cancer molecular diagnostic market.
Genomic Health and Myriad Genetics both made presentations to the investment community last week about their genomic tests that gauge a man's risk of prostate cancer aggressiveness. As part of its annual investor day, Myriad discussed new data on its Prolaris test, which analyzes the expression level of 46 cell cycle progression genes and stratifies men's risk of biochemical recurrence of prostate cancer. If the test reports low gene expression, then the patient is at low risk of disease progression, while high gene expression is associated with disease progression.
Meanwhile, around the same time last week, Genomic Health launched its Oncotype DX prostate cancer test and presented data from the first validation study involving the diagnostic. The Oncotype DX prostate cancer test analyzes the expression of 17 genes within four biological pathways to gauge prostate cancer aggressiveness. The test reports a genomic prostate score from 0 to 100; the lower the score the more certain a patient can be that they can avoid treatment and continue with active surveillance. Prostate cancer patients who are deemed to be at very low risk, low risk, or intermediate risk of progressing are eligible to be tested with the Oncotype Dx test. If, based on standard clinical measures, a person's prostate cancer is considered high risk, then he is not a candidate for Genomic Health's test.
These molecular tests are entering the market at a time when currently available tools aren't specific enough to distinguish between men who have an aggressive form of prostate cancer and therefore, need invasive treatments, and those that are low risk and can do well with active surveillance. According to an NIH estimate, in 2010, the annual medical costs associated with prostate cancer in the US were $12 billion.
It is estimated that each year 23 million men undergo testing for prostate specific antigen, a protein produced by the prostate gland that increases when a man has prostate cancer. Additionally, one million men get a prostate biopsy annually, while 240,000 men end up with a diagnosis for prostate cancer, and around 30,000 die from the disease. Although most of the men diagnosed with prostate cancer end up receiving surgery or radiation treatment, as many as half of these men will probably not progress, and their disease isn't life threatening.
While PSA testing has been shown to reduce prostate cancer deaths, a man's PSA level may be increased for reasons other than cancer. As such, broadly screening men for PSA has been controversial in the healthcare community since the test isn't specific enough to gauge which men are at low risk of developing aggressive prostate cancer and can forgo unnecessary treatments that can have significant side effects.
Both Myriad and Genomic Health are hoping their tests will further refine prostate cancer diagnosis and help doctors gain more confidence in determining which of their patients have aggressive disease and which are at low risk.
In this highly competitive space, Myriad has the first mover advantage, having launched Prolaris three years ago. The company has published four studies involving the test and conducted a number of trials analyzing around 3,000 patient samples.
Researchers from UCSF and Myriad recently published the fourth validation study in the Journal of Clinical Oncology, which analyzed samples from 400 men who had undergone a radical prostatectomy. In the published study, researchers reported that 100 percent of the men whom Prolaris deemed to be at "low risk" of progression did not experience a recurrence within the five years the study was ongoing. Meanwhile, 50 percent of those the test deemed to be a "high risk" did experience recurrence during that time (PGx Reporter 3/6/2013).
At a major medical conference recently, Myriad presented data from a study which tested biopsy samples from 141 patients treated with electron beam radiation therapy and found that the test score was significantly associated with patients' outcome and provided information about disease progression beyond standard clinical measures. Although this finding needs to be further validated in a larger patient cohort, the researchers concluded that Prolaris "could be used to select high-risk men undergoing electron beam radiation therapy who may need combination therapy for their clinically localized prostate cancer." In this study, around half of the cohort was African American.
Myriad has also shown in studies that its test can make accurate predictions from tissue from an initial prostate biopsy and from post-prostatectomy. The test has also shown in studies to be superior to the Gleason score, baseline PSA levels, and other prognostic factors in predicting prostate cancer-specific mortality.
Myriad has nearly completed hiring a 24-person sales force to drive sales of the test. Over the last year, Myriad has received more than 3,000 orders for its Prolaris test and 350 urologists have ordered it. The test carries a $3,400 price tag.
Although the company doesn't have Medicare coverage yet for Prolaris, Myriad is conducting a study, called PROCEED, that it hopes will sway Medicare contractor Noridian to cover the diagnostic. The company has said it is on track to submit data from this registry to Medicare by late summer and expects to hear a decision about test coverage in calendar year 2014 (PGx Reporter 5/8/2013).
During the annual investor day last week, Myriad officials highlighted the gene panel for Prolaris, which features genes involved in cell cycle progression, and noted this as one of the advantages of its test over standard methods. "The Prolaris score measures how fast the tumor is growing. We look at the cell proliferation to look at a component of cancer that is not looked at by current clinical pathologic features," Bill Rusconi, head of Myriad's urology division, said.
"So, pathology like PSA score … only look at how far the tumor is progressed … [and] how advanced that tumor is. So, that’s only half of the picture because an advanced tumor could have been smoldering for 20 years, and may not go much further in the short term," he noted. On the other hand, Rusconi added that a less advanced tumor could be progressing very quickly.
Another distinguishing point for the Prolaris test, according to Myriad, is that it is indicated for patients who are deemed to be at low and high risk by standard measures. Prostate cancer patients deemed to be at high risk of progression by standard clinical measures wouldn't qualify for testing by Genomic Health's test. Rusconi estimated that if Prolaris tested around 200,000 patients with localized prostate cancer to gauge the aggressiveness of their disease, the market opportunity for the test would be $700 million.
Myriad executives declined to comment on competing prostate cancer molecular tests, particularly Genomic Health's product, noting that there isn't a lot of published data to make any judgments. "We haven’t really seen any published data from any other competitor product. And so, I think in the absence of that, until data have made it through the peer review process and been in publication, it’s always difficult to understand exactly what type of information is available," Mark Capone, president of Myriad Genetics Laboratories, told investors.
Like Myriad's BRACAnalysis test, which comprises more than 80 percent of its product revenues, Genomic Health's Oncotype DX breast cancer recurrence tests is bringing in the majority of its product revenues. However, the company believes that its newly launched Oncotype DX prostate cancer test stands to be its largest market opportunity to date.
Last week, researchers from University of California, San Francisco, presented data from the first validation study involving the Oncotype DX prostate cancer test. The study involved nearly 400 prostate cancer patients considered low or intermediate risk by standard methods such as Gleason score and showed that when the Oncotype DX score was used in conjunction with other measures, investigators identified more patients as having very low risk disease who were appropriate for active surveillance than when they diagnosed patients without the test score.
More than one third of patients classified as low risk by standard measures in the study were deemed to be "very low risk" by Oncotype DX and therefore could choose active surveillance. Meanwhile, 10 percent of patients in the study were found by clinical measures to be at very low risk or low risk, but the Oncotype DX test deemed them as having aggressive disease that needed treatment.
Matthew Cooperberg of UCSF, who presented data from this validation study at the American Urological Association's annual meeting last week, highlighted this feature of the Oncotype DX prostate cancer test to investors during a conference call last week. He noted that the test not only gauges which low-risk patients can confidently remain with active surveillance, but it also finds those patients who didn't receive an accurate risk assessment based on standard clinical measures. "It's also equally important that we identify the man who frankly should not be on active surveillance, because they're out there," he said.
Genomic Health has aligned its test with guidelines from the National Comprehensive Cancer Network, which has expressed concern about over-diagnosis and over-treatment in prostate cancer patients. In 2010, NCCN guidelines established a new "very low risk" category for men with clinically insignificant prostate cancer and recommended that men who fall into this category and have a life expectancy of more than 20 years should only be followed with active surveillance. In 2011, NCCN made the active surveillance criteria more stringent for men in the "very low risk" category.
In order to develop the prostate cancer test, Genomic Health collaborated with the Cleveland Clinic on six feasibility studies and selected the gene expression panel after analyzing 700 genes on tissue samples from 700 patients. The commercial test analyzes the expression of 17 genes across four biological pathways.
Genomic Health executives suggested to investors that in determining the aggressiveness of prostate cancer a test that gauges critical genes in multiple pathways involved in the disease, as opposed to just one pathway, may be the better bet.
"After we selected those 700 [candidate] genes, we were completely agnostic as to what the best predictors would be. So, we let the genes do their thing and picked out the best performance," said Eric Klein, chairman of Glickman Urological and Kidney Institute at the Cleveland Clinic and principal investigator for the original development studies for the Oncotype DX prostate cancer test. Referring to Myriad's test, which assessed 46 cell cycle progression genes, Klein noted that while cell proliferation is important, it's not the only pathway.
"So, I think one of the strengths of this assay is that it surveys the biology of the cancer better because it surveys other pathways," he said. If a test only looks at genes in only one particular pathway, and the "score is low, you don't know if you have missed the other underlying biology."
This strategy of picking critical cancer-linked genes from multiple pathways has proven successful when launching Oncotype DX tests for breast cancer and colon cancer recurrence, company officials noted. Genomic Health's prior experience launching molecular tests for cancer recurrence and the strength of the Oncotype DX brand will likely be advantages for the company.
Kim Popovits, CEO of Genomic Health, noted that the company has hired a "small sales force" to drive uptake of the prostate cancer test and reps will be targeting high-volume practices. "We have medical science liaisons that will be out there working to educate key opinion leaders with a similar approach to what we did in breast [cancer]," Popovits told investors. "We will begin to add to the sales organization as time goes on, as we see traction taking place, and as we move more towards payor reimbursement."
The company plans to conduct a decision impact study as part of its effort to gain reimbursement coverage for the test. Genomic Health is also planning to do additional studies that will explore what level of active surveillance doctors should perform on patients who are deemed by the Oncotype DX test to be at very low or low risk.
The list price for the test is $3,820.
Although Myriad and Genomic Health are currently the main players in the prostate cancer molecular diagnostics space, the market will become an increasingly crowded one in the coming months.
Canadian firm GenomeDx is planning to launch a prostate cancer molecular diagnostic later this year, called Decipher. The company recently presented data at a medical conference on the test's clinical validity and utility in predicting which patients are at risk of recurrence and metastasis after prostate cancer surgery. The company has said it has 22 studies underway with the Decipher test involving 4,000 patients (PGx Reporter 2/20/2013).
BioTheranostics recently published a study in the Proceedings of the National Academy of Sciences about its new 32-gene signature test, dubbed Prostate Cancer Index, which gauges PSA recurrence. In the study, which involved 270 tumor samples for patients treated with radical prostatectomy, the RT-PCR test (developed in collaboration with Massachusetts General Hospital) predicted PSA recurrence and had added value over standard measures such as Gleason score, tumor stage, surgical margin status, and pre-surgery PSA levels. The only other measure with significant prognostic value was surgical margin status.
The test could separate patients into groups based on PSA recurrence and whether they would develop metastatic disease within a 10-year period. PCI found that patients with a high risk score had a 14 percent risk of metastasis, while those in the low-risk group had a zero percent risk of metastasis. "In particular, this information may be useful at the biopsy stage, so that clinicians can better assess which patients can consider active surveillance versus those who should consider immediate treatment," BioTheranostics CEO Richard Ding told PGx Reporter.
BioTheranostics has not yet determined when it will launch PCI. However, the company is planning additional follow-on studies to demonstrate the clinical utility of the test, including one study involving patients on active surveillance after having an initial prostate biopsy.