Results of a Comparative Effectiveness Claims Analysis from a Large Commercial Payer, Presented at the AHA Scientific Sessions 2018, Reinforce the Clinical Utility of the Corus® CAD Blood Test in the Outpatient Assessment of Obstructive CAD

Palo Alto, California, UNITED STATES

– Patients Who Received the Corus CAD Test Experienced Significantly Lower Rates of Downstream Invasive Coronary Angiography, CAD-Related ER and Doctor Visits, Hospitalizations, and Noninvasive Cardiac Testing than Usual Care

REDWOOD CITY, Calif. , Dec. 17, 2018 (GLOBE NEWSWIRE) -- CardioDx, Inc., a molecular diagnostics company specializing in cardiovascular genomics, announced results from a large, comparative effectiveness claims analysis using commercial and Medicare Advantage claims data from Optum (United Healthcare was presented as an oral session at the American Heart Association Scientific Sessions 2018 in Chicago, IL, on November 11, 2018.  

The analysis found that commercial patients with symptoms suggestive of obstructive coronary artery disease (CAD)* and who received the Corus CAD blood test had significantly lower rates of downstream healthcare resource utilization – lower rates of invasive coronary angiography procedures, revascularization procedures, CAD-related visits¥ and hospitalizations, and noninvasive cardiac testing§ - without increased adverse cardiac event rates as compared to traditional cardiac testing at 6-month follow-up.  Corus CAD is a precision medicine blood test that integrates age, sex, and gene expression levels into a single score (1-40 scale) indicating the current likelihood of a significant narrowing or blockage in the coronary arteries.

Coronary artery disease is a leading cause of death in the U.S., resulting in one in seven deaths per year.1   Every day, approximately 8,000 patients present to primary care clinics with signs and symptoms of obstructive CAD for evaluation.   Yet, the evaluation of patients presenting with symptoms suggestive of obstructive coronary artery disease is less than optimal, resulting in unnecessary testing due to inefficiencies in the healthcare system and thus leading to increased healthcare costs. 

The objective of this comparative effectiveness claims analysis was to use insurance claims data (Optum claims database from January 1, 2015 to October 31, 2017) to analyze the clinical actions taken in real-world, clinical practice among patients receiving the Corus CAD test and comparing them to a matched cohort of similar patients undergoing traditional cardiac testing and who did not receive the Corus CAD test.  A total of 5500 patient were included in this analysis, 1100 patients in the Corus CAD cohort and 4400 patients in the traditional cardiac testing (or usual care) cohort during this time period.

Results showed that the frequency of non-invasive cardiac studies was 30% lower in the Corus CAD cohort compared with traditional cardiac testing group at 180 days (21.6% vs. 30.9%,; P<.001 ).  Similarly, rates of invasive coronary angiography were 60% lower in the Corus CAD cohort at 180 days (2.6% vs. 6.5%, respectively; P<.001), and rates of coronary artery revascularization (0.8 vs. 2.1%; P=.001) was 62% lower in the Corus CAD cohort. There was no difference in major adverse cardiac events among the two cohorts (0.3% vs. 0.5%; P=.46).

Study authors concluded that in the real-world setting, the use of the Corus CAD test in stable patients presenting with symptoms suggestive of obstructive for CAD in the outpatient setting was associated with subsequently lower rates of CAD-related resource utilization without an increase in intermediate-term cardiac events.  These findings suggest that the appropriate adoption of the Corus CAD blood test in the workup of patients may lead to improved resource utilization and better patient care.

About Obstructive Coronary Artery Disease
Coronary artery disease (CAD) is a very common heart condition in the United States. One in seven deaths among Americans is caused by CAD.1  CAD can cause a narrowing or blockage of the coronary arteries (vessels to the heart that supply the heart with blood, oxygen, and nutrients), reducing blood flow to the heart muscle. This narrowing or blockage in the coronary arteries is often referred to as obstructive CAD, characterized by the presence of atherosclerosis, or plaque.

About the Corus CAD Test
Corus CAD is the first and only commercially available blood test that can safely and conveniently help primary care clinicians and cardiologists assess stable non-diabetic patients’ symptoms for obstructive coronary artery disease. The test incorporates age, sex and gene expression measurements into a single score that indicates the likelihood of obstructive CAD. Clinicians use the Corus CAD score, along with other clinical information, to determine whether further cardiac testing is necessary, which can help patients avoid unnecessary exposure to radiation associated with medical imaging testing, as well as possible reactions to imaging dyes and/or potential complications from invasive cardiac procedures. The test involves a routine blood draw that is conveniently administered in the clinician's office. The Corus CAD test is the only sex-specific test for the evaluation of obstructive CAD because it accounts for cardiovascular differences between men and women.

The test has been clinically validated in independent male and female patient cohorts, including two prospective, multicenter U.S. studies, PREDICT and COMPASS.2,3 In the COMPASS study, the Corus CAD test outperformed myocardial perfusion imaging (MPI) as a diagnostic tool to exclude obstructive CAD by demonstrating a higher negative predictive value (96% vs. 88%, p<0.001) than MPI for assessing the presence of obstructive CAD.3,5   In the NHLBI-sponsored PROMISE Corus CAD substudy, Corus CAD demonstrated similar clinical outcomes to MPI and coronary CT-angiography at 25 months follow-up (3.2% vs. 2.6%, p=0.29). 4 To date, over 275,000 Corus CAD test results have been resulted and provided to clinicians commercially. CardioDx processes all Corus CAD test samples at its CLIA-certified and CAP-accredited clinical laboratory in Redwood City, California.

The Corus CAD test has been recognized by The Wall Street Journal's Technology Innovation Awards, honored as a Gold Edison Award recipient, and named one of TIME's Top 10 Medical Breakthroughs in 2010.

About CardioDx
CardioDx, Inc., a molecular diagnostics company specializing in cardiovascular genomics, is committed to developing clinically validated tests that empower clinicians to better tailor care to each individual patient. Strategically focused on coronary artery disease, CardioDx is committed to expanding patient access and improving healthcare quality and efficiency through the commercialization of genomic technologies. Please visit for additional information.

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* Obstructive CAD is defined as at least one atherosclerotic plaque causing ≥50% luminal diameter stenosis in a major coronary artery (≥1.5 mm lumen diameter) as determined by invasive quantitative coronary angiography (QCA) or coronary computed tomography angiography (CTA) (≥2.0 mm).
¥  CAD-related visits:  Emergency room and clinic visits
§  Noninvasive cardiac testing:  Myocardial perfusion imaging (MPI), stress EKG, stress echo, or coronary CT-Angiography


1 Benjamin EJ, Virani SS, Callaway CW, et al. On Behalf of the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Heart Disease and Stroke Statistics – 2018 Update:  A Report from the American Heart Association. Circulation. 2018;137:e67-e492.
2 Rosenberg S, Elashoff MR, Beineke P, et al. Multicenter Validation of the Diagnostic Accuracy of a Blood-Based Gene Expression Test for Assessing Obstructive Coronary Artery Disease in Nondiabetic Patients. Ann Intern Med. 2010;153:425-434.
3 Thomas GS, Voros S, McPherson JA, et al. A Blood-Based Gene Expression Test for Obstructive Coronary Artery Disease Tested in Symptomatic Nondiabetic Patients Referred for Myocardial Perfusion Imaging: The COMPASS Study. Circ Cardiovasc Genet. 2013;6(2):154-162.
4 Voora D, Coles A, Lee KL, et al. An Age- and Sex-Specific Gene Expression Score is Associated With Revascularization and Coronary Artery Disease:  Insights From the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) Trial.  Am Heart J. 2017;184:133-140. 
5 The COMPASS study demonstrated that the Corus CAD algorithm has an NPV of 96% and 89% sensitivity at the score threshold of 15 in a population of men and women referred to MPI.