In short
Flurpiradaz F 18 is a radioactive diagnostic drug used as an imaging tracer for positron emission tomography (PET) scans of the heart. It is approved in the United States under the brand name Flyrcado to evaluate blood flow to the heart muscle in adults with known or suspected coronary artery disease.
Key points
- Flurpiradaz F 18 is an FDA-approved radioactive tracer for PET myocardial perfusion imaging, marketed as Flyrcado.
- The trial registered in CTIS is a Phase 2 study with 109 participants and is currently authorised.
- The trial investigates XC001, not Flurpiradaz F 18; Flurpiradaz F 18 serves as an auxiliary imaging agent.
- The condition studied is refractory angina due to obstructive coronary artery disease.
- The primary endpoint measures therapy response at weeks 12 and 26, combining exercise duration, angina episodes, and ischemic burden on PET imaging.
- Flurpiradaz F 18 is given by intravenous injection as a solution for injection.
What is Flurpiradaz F 18?
Flurpiradaz F 18 is a radioactive diagnostic drug, also known as a radiotracer, used in positron emission tomography (PET) imaging of the heart. It is marketed in the United States under the brand name Flyrcado and was first approved by the US Food and Drug Administration in 2024. It is described as the first FDA-approved radiotracer for cardiac imaging in 30 years.
Chemically, Flurpiradaz F 18 is an analog of pyridaben, a mitochondrial complex 1 (MC-1) inhibitor. In the CTIS product records, the substance is listed as a chemically synthesised substance with no marketing authorisation in the EU — it remains an investigational substance in this registry. The product in the trial is supplied by Xylocor Therapeutics Inc.
How does Flurpiradaz F 18 work?
Flurpiradaz F 18 is extracted by the heart muscle (myocardium) in proportion to blood flow and binds to mitochondrial complex 1. Because it carries the radioactive isotope fluorine-18, its distribution in the heart can be detected by a PET scanner. Areas of the heart that receive less blood flow — for example because of narrowed coronary arteries — take up less of the tracer, which allows doctors to see regions of reduced blood supply (ischemia) or damaged heart muscle (infarction) on the scan.
Which conditions is it used or studied for?
- Known or suspected coronary artery disease (CAD) — Flurpiradaz F 18 is indicated for PET myocardial perfusion imaging in adults with known or suspected CAD to evaluate for myocardial ischemia and infarction.
- Refractory angina due to obstructive coronary artery disease — In the CTIS trial, Flurpiradaz F 18 is used as an imaging agent to measure ischemic burden during stress PET imaging in participants with this condition.
How is Flurpiradaz F 18 given?
Flurpiradaz F 18 is given by intravenous injection as a solution for injection. In the CTIS trial, the recorded dose is 6.5 millicuries (mCi) given intravenously. The product information for Flyrcado gives recommended administered activities depending on the type of imaging: 93–111 MBq (2.5–3 mCi) for rest imaging, 222–241 MBq (6–6.5 mCi) for pharmacologic stress imaging, and 333–352 MBq (9–9.5 mCi) for exercise stress imaging on the same day.
What do the clinical trials show?
One trial in the EU Clinical Trials Information System involves Flurpiradaz F 18. The trial, identified as 2024-514874-36-01, is a Phase 2 interventional study with 109 participants and is currently authorised. In this trial, Flurpiradaz F 18 is not the substance being tested; it serves as an auxiliary imaging agent. The investigational drug is XC001, which is delivered directly into the heart muscle via a catheter.
The trial enrols participants with refractory angina due to obstructive coronary artery disease — chest pain caused by narrowed heart arteries that has not responded adequately to other treatments. The study uses Flurpiradaz F 18 PET imaging to assess ischemic burden, one of three components of the primary composite endpoint. The other components are total exercise duration on a treadmill test and angina episodes recorded in a patient diary.
The primary endpoint, for Part 2 of the trial only, compares the average proportion of participants with a therapy response at week 12 and week 26 between the XC001 group and a sham procedure group. All exercise testing and imaging are assessed by blinded core laboratories.
What side effects are known?
No data are available on the use of Flurpiradaz F 18 in pregnant women to inform a drug-related risk. All radiopharmaceuticals have the potential to cause fetal harm depending on the fetal stage of development and the magnitude of the radiation dose. The product contains ethanol, and studies have shown that ethanol is associated with central nervous system abnormalities, behavioural disorders, and impaired intellectual development. It is not known whether Flurpiradaz F 18 is excreted into human milk. If use of the drug is deemed necessary, breastfeeding should be interrupted and expressed feeds discarded for a minimum of 8 hours after administration. The prescribing information lists no contraindications.