A closer look at how FDA's flurpiridaz approval will impact nuclear cardiology
After 17 years of research and development, flurpiridaz F-18 (Flyrcado), a new positron emission tomography (PET) radiotracer that was shown in trials to be much better than traditional SPECT, is poised to revolutionize cardiac nuclear imaging, according to numerous nuclear imaging experts. Cardiovascular Business spoke with Jamshid Maddahi, MD, a professor of molecular and medical pharmacology at UCLA and director of the Biomedical Imaging Institute at UCLA, about the approval's long-term impact. He was the principal investigator for the AURORA Phase III clinical trial, giving him a unique perspective on this big moment.
Maddahi believes this new radiotracer could transform the field of cardiology and lead to much wider adoption of PET for cardiac imaging. Flurpiridaz offers significant advantages over the current primary tracer, rubidium-82, with requires an expensive generator. Maddahi said flurpiridaz will make PET more accessible and cost-effective to deliver more accurate diagnoses of coronary artery disease (CAD) and the ability for additional information from assessing myocardial blood flow.
"I would say that flurpiridaz is actually going to be a game-changer in a noninvasive diagnosis of coronary artery disease and assessment of myocardial blood flow. The whole field of nuclear cardiology and cardiology have been waiting for a long time to get to this point," Maddadi said.
"There are several features of flurpiridaz that makes it unique. It uses an F-18 label, which has a longer half-life than what is currently available with rubidium. Instead of being 75 seconds with rubidium, it has a 109-minute half-life. It makes it possible that the tracer can be made in the commercial cyclotrons or the regional cyclotrons that are already in place throughout the U.S., so institutions that are interested in doing the test can order a single dose rather than having to commit to buying rubidium-82 generator," Maddahi explained
These Rb-82 generators cost between $35,000-$40,000 per month, so only centers with high volumes of cardiac patients can justify using PET. The ability to buy unit doses on demand will make PET much more economical.
PET also offers improved imaging. Maddahi noted that the AURORA trial, which compared flurpiridaz PET to SPECT, found several cases where SPRECT was inconclusive or showed normal perfusion, but the flurpiridaz scans showed the patient actually had perfusion defects that SPECT missed.
With this improved accessibility and diagnostic precision, Maddahi and other experts believe flurpiridaz will significantly push the adoption of PET imaging in nuclear cardiology. Currently, only 8% of PET studies in the U.S. are focused on myocardial perfusion. Flurpiridaz is expected to shift this balance by leveraging the existing network of cyclotrons that distribute FDG tracers for oncology, allowing more widespread use of PET for cardiac imaging.
Another major advantage of flurpiridaz is the ability to conduct treadmill stress tests, which are considered a gold standard compared to the pharmacological stress currently required when using rubidium. Maddahi said treadmill testing offers a more physiologically accurate assessment of heart function under stress.
In the long term, flurpiridaz has the potential to improve the detection of CAD and help diagnose conditions like microvascular disease, which cannot be detected by traditional methods. As Maddahi explains, the high extraction fraction of flurpiridaz allows for more accurate flow measurements, providing critical insights into blood flow abnormalities at the capillary level. This could lead to earlier diagnosis and better management of heart disease in patients who may otherwise go undiagnosed.
Maddahi, who has dedicated much of his career to advancing cardiac imaging, is optimistic that this new technology will usher in a new era of improved diagnosis and care for heart disease patients.
“I feel quite good about this,” Maddahi said, reflecting on his 47-year career in nuclear cardiology. “We have been able to reach the pinnacle of myocardial perfusion imaging with flurpiridaz.”
Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: dfornell@innovatehealthcare.com