Lantheus Medical Imaging has presented preliminary data from a multicenter Phase 2 clinical trial that showed that Positron Emission Tomography (PET) imaging with its investigational agent flurpiridaz F 18 injection provided better image quality than technetium-99m sestamibi single photon emission computed tomography (SPECT), the current standard for the non-invasive detection of coronary artery disease (CAD).
The data also indicated that PET imaging with flurpiridaz F 18 (formerly known as BMS747158) injection rendered a significantly larger perfusion defect size when compared with the corresponding defects seen in SPECT imaging.
Twenty-six patients in a single study center underwent SPECT and PET imaging within six months. PET myocardial perfusion imaging was performed with flurpiridaz F 18 injection at rest and was then followed one hour later with imaging at exercise or under pharmacologically-induced (adenosine) stress. PET and SPECT image quality were assessed by two independent, blinded readers and graded as excellent, good or fair.
Stress and rest perfusion defects on PET and SPECT were assessed by the same readers by computer-assisted visual interpretation using the standard 17 segment, 5-point scoring model. The extent and severity of ischemia (summed difference scores (SDS)) were derived from the difference between summed stress scores (SSS) and the summed rest scores (SRS).
Findings showed that image quality with flurpiridaz F 18 PET was excellent in 24 and good in 2 patients, in contrast to image quality with SPECT which was excellent in 17, good in 8 and fair in 1 patient. In 14 patients with abnormal SPECT, mean SDS was greater with PET than with SPECT. In all 12 patients with normal SPECT, SDS was zero with both PET and SPECT.
Dana Washburn, vice president of clinical development and medical affairs at Lantheus Medical Imaging, said: “Although these data will need to be confirmed by results from other sites and from subsequent larger clinical trials, they suggest that flurpiridaz F 18 PET myocardial perfusion imaging may provide improved image quality and an increase in defect size compared to SPECT.
“The data also suggest that PET imaging with flurpiridaz F 18 injection can be performed using exercise or pharmacological stress, which offers a potential advantage over existing PET MPI agents on the market.”
Daniel Berman, chief of cardiac imaging and nuclear cardiology at Cedars-Sinai Medical Center, said: “These encouraging preliminary data from our clinical research site show that PET imaging with flurpiridaz F 18 injection provided improved image quality and an increase in defect size compared to SPECT. A PET imaging agent that may provide higher quality images with more obvious perfusion defects can have a profound effect on physicians’ ability to make more definitive assessments of coronary artery disease.”