NEW YORK (GenomeWeb) – Kirkland, Washington-based Prevencio is working on finishing development of its multi-protein test for coronary artery disease and is aiming to submit the test to the US Food and Drug Administration in 2018.
The test, called the HART CAD, detects obstructions in coronary arteries with accuracy levels that are noticeably higher than those provided by standard cardiac tests, according to the firm. HART CAD, which applies a diagnostic score using a panel of clinical variables and proteins, is being developed in collaboration with researchers at Massachusetts General Hospital.
James Januzzi, the principal investigator and a practicing cardiologist at Mass General, presented results on the test recently in a Late-Breaking Science presentation at the European Society of Cardiology Congress in Rome. According to Prevencio, the data presented provide a basis for completing the test kit and preparing a clinical trial in advance of submitting the test for clearance by the US Food and Drug Administration.
Using a proteomics approach, Prevencio identified a unique combination of proteins that can differentiate patients with clinically significant obstructive coronary artery disease from those who do not. The HART CAD test includes clinical parameters such as gender and history of percutaneous coronary intervention and measures the quantity of four proteins — adiponectin, apolipoprotein C-1, kidney injury molecule-1, and midkine. Taken together, the proteins represent a unique pathophysiologic mix of abnormal glucose and fatty acid metabolism, hyperlipidemia, renal dysfunction, vascular injury, and plaque infiltration, according to the test's developers. The proteins provide orthogonal information that adds independent value to the clinical variables, according to the developer.
The Prevencio and Mass General team used immunoassays to detect the quantity of blood proteins and analyze the clinical variables as part of a study in which 927 subjects undergoing coronary angiography were considered for the presence or absence of greater than 70 percent obstruction in at least one major coronary artery. The test's accuracy was represented by measuring the area under the receiver operating characteristic curve, or AUC. The AUC for stress tests involving the use of treadmills was 0.52. By contrast, the AUC for the HART CAD was 0.87.
Although none exists, a perfect test would provide a reading of 1. "An AUC of 0.52 means the test is hit or miss, or highly inaccurate," Rhonda Rhyne, president and CEO of Prevencio, told GenomeWeb. "To achieve 0.87 when the standard of care is 0.52 is an advance in determining whether the patient has an obstruction and whether they really need to go to the catheterization lab."
Current coronary artery disease testing modalities, such as stress testing and the use of cardiac CT, have limitations, according to Pervencio, including variable accuracy, high costs, and the need for ionizing radiation with adjunctive imaging for stress testing. Emergency room physicians and cardiologists use electrocardiograms and a single-analyte protein, troponin, as part of a biomarker test that diagnoses patients, Rhyne said.
"Whereas troponin protein blood tests analyze one individual protein at a time and tell if a patient has already had a heart attack, our blood tests analyze multiple proteins and algorithmically score a patient to determine the absence or presence of coronary artery disease and whether there is a risk of a heart attack," Rhyne said. In clinical studies for the HART CAD panel, subjects with an elevated score had a likelihood of 70 percent or greater obstruction in the coronary arteries and had a shorter time to a heart attack than subjects with a lower score.
The company is also developing tests to predict whether patients have a one-year risk for heart attack, stroke, or cardiovascular death, or a composite of each condition, she added.
According to Prevencio, up to 50 percent of patients are unnecessarily referred for invasive coronary catheterization, subjecting them to additional ionizing radiation and the potential for complications, including death. A non-invasive, low-cost, and safe test, such as HART CAD, would be valuable and potentially result in reduction of morbidity, mortality, and healthcare costs, Rhyne said.
"More than one million people per year in the US are sent to the cardiac catheterization laboratory as in-patients, and approximately 50 percent of those being given a cardiac catheterization are not obstructed," Rhyne said. "Cardiac catheterizations carry a 1 percent mortality and they are billed at up to $47,000 per procedure. So, with one million procedures, we are spending approximately $47 billion per year on in-patient cardiac catheterizations."
Prevencio's low-cost blood test — the company is estimating it will cost around $400 per test — would take less than 2 hours from sample to result, Rhyne said, and it would tell patients whether they have an obstruction and need to go to the catheterization laboratory or not.
The next step for the company is to develop a diagnostic test kit that it expects to complete in 2017. Prevencio's objective, after conducting a trial using the diagnostic test kit, is to submit the kit to the US Food and Drug Administration for review in the middle of 2018.
Prevencio initially had plans to launch the test around the end of 2016 or early in 2017. But it later decided to expand clinical work to include prognostic test capabilities and thereby increase the value of the company, Rhyne said.
The total available market in the US for use of the test in the emergency room is $3.20 billion, according to Prevencio. The test could also be adopted in emergency rooms outside the US and in cardiology clinics and clinical laboratories worldwide.
Prevencio is seeking partners and funding to support completion of the test kit and for conducting the clinical trial in advance of its FDA submission. The firm said that it recently raised $2 million in private financing and is looking to raise an additional $18 million in Series C funding.
Among Prevencio's current partners are Mass General, for work involving patient samples and analysis, and Myriad RBM, a subsidiary of Myriad Genetics, on work related to protein assays.
Among other molecular diagnostic players in the coronary disease space, Somalogic has developed a nine-protein panel for assessing the risk of adverse cardiovascular events in patients with coronary heart disease.
In June, the company published a paper describing the panel in the Journal of the American Medical Association and this fall, it plans to launch it as a commercial test performed by its CLIA lab.
Also, in 2014, CardioDx announced the close of a $35 million financing round, and said that it would use the funds to expand the commercial use of Corus CAD, a gene expression-based test for assessing non-diabetic patients who display symptoms suggestive of obstructive CAD, and to support the company's development of other genomic tests for coronary artery disease. Rhyne previously told GenomeWeb that the HART CAD test will be cheaper and provide results faster than the Corus CAD test.