Originally published August 10.
Medicare contractor Palmetto GBA announced this week that it will cover CardioDx's Corus CAD gene expression test for coronary artery disease, saying that the test meets criteria for analytical validity, clinical validity, and clinical utility as a reasonable and necessary Medicare benefit.
CardioDx believes the decision, which makes Corus CAD a covered benefit for more than 40 million Medicare enrollees, lowers the first major barrier to physician adoption of the test. According to CardioDx CEO David Levison, the company is also hopeful Palmetto's announcement will boost its ongoing efforts to gain similar coverage by private payors.
"The Medicare decision is not only an enormous health plan for us – almost 40 million covered lives – but also the cornerstone for our strategy with commercial payors," Levison told PGx Reporter this week.
"One of the first things we often get asked when we go to talk to commercial payors is, 'What is Medicare doing?' So it's great to have them in our corner, saying [they've] fully vetted this test from clinical validity, utility, and economic utility standpoints," he said.
"We think that will be very reassuring to commercial payors and accelerate their process."
CardioDx runs Corus CAD, which gauges the expression of 23 genes via real-time PCR, at its CLIA-certified laboratory in Palo Alto, Calif. Gene expression levels are interpreted through the company's Corus CAD software and the patient's genetic test results are sent in a report to the ordering physician.
Since launching the test in 2009, the company has been collecting clinical utility and cost data to expand insurance reimbursement of the test, which is used to determine which patients have or don't have CAD.
In May 2011, CardioDx raised $60 million in private financing to fund studies to back up the clinical utility of Corus CAD, continue to educate primary care physicians and cardiologists on how the test can be used in clinical care, and to reach out to payors to help them understand the circumstances under which they should pay for the test (PGx Reporter 5/18/2011).
Corus CAD has been clinically validated in two prospective, multi-center US trials, PREDICT and COMPASS, while additional studies, like the Investigation of a Molecular Personalized Coronary Gene Expression Test on Cardiology Practice Pattern, or IMPACT, trial, have demonstrated that it can change patient management decisions in both primary care and cardiology practices.
Levison said that the company has recently begun two registry studies to track additional data — one in collaboration with an unnamed payor partner, and the other using the company's broader cohort of commercial patients.
According to Levison, the COMPASS and IMPACT trials provided the backbone for the case CardioDx made to Palmetto and hopes to make to additional private payors. "Our strategy has been to initially work on getting physicians very comfortable with the clinical utility of the test, how to use it … [and] then to use physician adoption to really drive the clinical evidence we knew payors were going to want to see before they were willing to make a coverage decision," he said.
The prospective IMPACT trial, a study of 83 non-diabetic patients referred to Vanderbilt University Medical Center cardiologists, was designed to assess the effect of Corus CAD test scores on clinical decision-making.
"We compared what cardiologists did when they [saw] patients with stable chest pain without the information from our test with … what they would do with this one more piece of information, and [found] that … over 50 percent of the time, physicians made a different decision based on our test." Levison said.
"It was a good confirmation of what were we're hearing in the field … that doctors are using it to make better clinical decisions," he added.
In addition to fueling further coverage decision among private payors, CardioDx is also optimistic about the effect of Palmettos' decision on physician adoption. "Obviously physicians feel more comfortable ordering a test that will get reimbursed," Levison said.
The current standard method for diagnosing obstructive CAD is catheter-based coronary angiography, an invasive method that also can expose patients to radiation. CardioDx believe that the Corus CAD test offers advantages over other CAD diagnostics because it only requires patients to give a blood sample.
"While we believe there is a lot of clinical support in the physician community, even in the absence of full reimbursement, we believe the Medicare decision will just be another reason for physicians to feel comfortable ordering this," said Levison.
Eric Topol, director of the Scripps Translational Science Institute and the principal investigator of the PREDICT validation study of Corus CAD, offered a more cautious take. He told PGx Reporter that though Medicare coverage removes a huge adoption barrier, others still remain.
"[The test] hasn't gotten used for a few reasons. One was that there was no reimbursement. That was number one. But the second reason, which is still a challenging one, is that the reflex today for someone who has an ambiguous stress test is to undergo a coronary angiogram," he said.
Topol suggested that this reflex reflects the inertia of a "procedurally oriented" field. "It's unfortunate," he said, "because [angiography is] an invasive procedure, and it's expensive."
Corus CAD "basically challenges that, because … we know at least 20 to 30 percent of the over 2 million angiograms in the US each year are normal — no disease. So you could say they were unnecessary — especially if you had a blood test like this that could identify those folks before they have an unnecessary procedure," Topol explained.
Overall, he said, "The fact that there is reimbursement could make a difference … but it still isn’t clear whether cardiologists will be willing to forgo" angiography.
Topol argued that a strong driver for adoption of the test might actually come from patients themselves, and advocated better education of the public. "A patient could say, 'I don’t want to have an angiogram. I want to have that gene blood test first.' That could lead to really marked reduction of unnecessary angiograms," he said.
CardioDx's Levison estimated last May that doctors had so far used Corus CAD to gauge obstructive CAD in more than 13,000 patients. He updated that number this week to 30,000 tests run by the company.
Levison said that the firm is celebrating the Palmetto decision, and then plans to move toward building coverage among private payors, several of which he said are engaged in "ongoing dialogues" with CardioDx.