Abstract 18022: Improved Assessment of CAD in Women With Flurpiridaz F-18 PET Myocardial Perfusion Imaging: Results of Subset Analysis of the Flurpiridaz F-18 Phase 3 Study

Abstract

Background: Coronary artery disease (CAD) is under-diagnosed in women. Flurpiridaz F 18 injection (flurpiridaz) is a PET myocardial perfusion imaging (MPI) tracer in clinical development. We hypothesized flurpiridaz would result in improved CAD detection in women in comparison to SPECT. Methods: This Phase 3 study was designed to assess the diagnostic efficacy of flurpiridaz and SPECT with Tc99m-labeled agents for CAD detection in the same patients. Patients with known or suspected CAD who were either scheduled for or had completed invasive coronary angiography (without intervention) were included. Each patient was studied using both rest/stress flurpiridaz PET MPI and rest/stress Tc-99m labeled SPECT MPI. Images were interpreted by 3 expert readers blinded to all clinical information. Quantitative coronary angiography (QCA) was used with patients considered CAD positive with a stenosis ≥50% in at least one major vessel. Results: 795 subjects were enrolled at 72 clinical sites in US, Canada and Finland. The study included 235 (30%) evaluable female subjects with a mean age of 62.4±10.1 years, body weight of 85.0±21.6 kg, and a BMI of 32.3±7.8 (58.7% with a BMI≥30). The agent was safe and well tolerated. A statistically significant greater sensitivity was seen for flurpiridaz (67.8%) vs SPECT (37.3%, p<0.001). Similar specificity was shown for flurpiridaz (81.3%) vs SPECT (80.1%) (p=0.017 for non-inferiority testing). The diagnostic superiority of flurpiridaz vs SPECT was also demonstrated by ROC analysis (p<0.001). Statistical superiority of flurpiridaz vs SPECT was shown for diagnostic accuracy (p=0.014), image quality (p<0.001), and interpreter certainty (p<0.001), with a significant reduction (~50%) in radiation exposure for flurpiridaz vs SPECT (p<0.001). Conclusions: The results of this Phase 3 trial demonstrate the superiority of flurpiridaz over standard SPECT MPI for the assessment of CAD in women, with lower radiation exposure than standard SPECT.