While there is no crystal ball to see who is most likely to have a heart attack, the Cleveland Clinic (Cleveland, Ohio) has developed a new blood test that may be one approach to doing so and could become a standard in emergency rooms and primary care offices. According to a study published in The New England Journal of Medicine (NEJM), the test can identify those in danger of experiencing a heart attack within 30 days to six months. The groundbreaking work indicates that myeloperoxidase (MPO), which Cleveland Clinic researchers described as an "abundant leukocyte enzyme," is elevated in "culprit lesions that have fissured or ruptured in patients with sudden death from cardiac causes." Steven Nissen, MD, one of the study authors, told The BBI Newsletter that the test "seems to be a better predictor [of adverse outcome] than all of the other tests that are out there."
Reporting in the Oct. 23 edition of NEJM, the study authors said results identified patients at risk for cardiac events in the absence of myocardial necrosis, which indicates damage has already occurred to the heart. "We looked at more than 600 patients who came to the emergency room with chest pain," said Stanley Hazen, MD, PhD, head of the section of preventive cardiology at the Cleveland Clinic. "We found that adding MPO testing to current laboratory-based risk assessments increased our ability to predict future cardiac risks over the next 30 days to six months from 50% to 95% of the time."
Specifically, study results demonstrated initial plasma myeloperoxidase levels predicted the risk of myocardial infarction, even in patients who are negative for troponin T at baseline. According to the study, myeloperoxidase levels at presentation also predicted the risk of major adverse cardiac events (described as myocardial infarction, the need for revascularization or death within 30 days and six months after presentation of symptoms). In patients without evidence of myocardial necrosis, defined as those who were negative for troponin, the baseline myeloperoxidase levels independently predicted the risk of major adverse coronary events at 30 days and at six months.
ER physicians often have difficulty diagnosing the source of chest pains when patients present with that symptom, and they must make rapid decisions but have only three diagnostic tools to help them determine acute coronary distress (ACS). One is the electrocardiogram, which measures the electrical activity of the heart, but identifies less than half of patients with ACS. Existing tests measure other proteins, including troponin, myoglobin and C-reactive protein, but those proteins only become present in the blood after damage to the heart has already been done. Thus, the Cleveland Clinic said its test "is especially valuable for identifying at-risk patients not recognized by current diagnostic laboratory testing."
Nissen told BBI he conducted a study several years ago to "explore the sensitivity of troponin measurements as a means to detect adverse outcomes" of coronary heart disease. He and his fellow researchers stored samples of the patients' blood, and ultimately conducted this most recent test. Inflammation of the arteries is what led the researchers to look at myeloperoxidase, which is an "inflammatory enzyme activated in patients with coronary diseases," Nissen said.
Bill would block patent fee diversion
Medical innovators may not be surprised about lengthy product review times at the FDA, but they could become even more frustrated over the next few years when it comes to getting a patent from the U.S. Patent and Trademark Office (PTO; Arlington, Virginia). The average time it takes to receive a patent known as patent pendency will increase from the current 26 months to 45 months by the year 2008 unless Congress acts this year, according to an advocacy group, the 21st Century Intellectual Property Coalition (Washington). It said the soaring pendency times result from a 12-year history of diverting funds from the PTO to pay for unrelated government programs.
"Patents and trademarks are the currency that drives America's high-tech economy," the coalition wrote to Speaker of the House Dennis Hastert (R-Illinois) last month. "The PTO serves a critical role in the promotion and development of innovation and commercial activity in our country. Yet, issues of patent quality continue to result in substantial expensive litigation and uncertainty over legal rights in new products." The group noted that the PTO receives all of its funding from fees paid by those seeking patents and trademarks, but more than $650 million over the last 12 years has been diverted from the agency through the appropriations process to pay for other programs. As a result, this growing coalition of 91 businesses and 28 associations is lobbying Congress to pass H.R. 1561, the United States Patent and Trademark Office Fee Modernization Act of 2003, which passed the House Judiciary Committee this summer.
The Medical Device Manufacturers Association (MDMA; Washington) is among those supporting the coalition's efforts to get H.R. 1561 passed. "This legislation would take the patent user fees out of the hands of appropriations," Benjamin Wallfisch, policy director at MDMA, told BBI. "What happens is that the user fees end up all over the place in unrelated government programs." The appropriators "have discretion over it and can use it at will," he said. "MDMA believes the PTO serves an important role in ensuring the intellectual property rights of medical device innovators. Further, we think the government should use those fees paid by the industry for the purpose they were intended," Wallfisch added.
H.R. 1561 would end the fee diversion practice, but it probably also would serve to increase user fees. Despite a proposed user fee increase, the coalition said it fully supports the proposal. "America's innovators are prepared to pay out of their own pockets to improve the situation at the PTO, provided the money will go to the agency," the coalition said in its letter.
The chances of the legislation passing in this session of Congress remain uncertain, however, with lawmakers focusing on Medicare reform. Some of the life sciences member companies of the 21st Century Intellectual Property Coalition include Advanced Micro Devices (Sunnyvale, California); Agilent Technologies (Palo Alto, California); Amgen (Thousand Oaks, California); Athena Diagnostics (Worcester, Massachusetts); Aventis Pharmaceuticals (Strasbourg, France); and Boston Scientific (Natick, Massachusetts).