Head-to-Head PSMA PET Study Finds Lower Urinary Bladder Uptake Between 2 PSMA PET Radiopharmaceuticals
February 27, 2026 · News Release
Blue Earth Diagnostics reported results from the first prospective, multicenter, intra-patient comparator study evaluating urinary bladder standardized uptake values (SUV) and lesion detection for 18F-flotufolastat (POSLUMA®) versus 18F-piflufolastat in men with low prostate-specific antigen (PSA) biochemical recurrence (BCR) of prostate cancer following radical prostatectomy.
Across 55 evaluable patients, the study met its primary endpoint, demonstrating significantly lower urinary bladder radioactivity with POSLUMA—median bladder SUV mean of 10.9 vs 29.0 for piflufolastat (median difference 15.1; p < 0.001). Reduced urinary activity is particularly relevant for PET interpretation, as high bladder uptake can obscure subtle recurrence in the prostate bed and adjacent pelvic lymph nodes, a known limitation of PSMA-targeted agents with renal excretion.
Secondary analyses suggested higher detection rates with POSLUMA at both patient and region levels, including among those with very low PSA (≤ 0.2 ng/mL). In this subgroup, majority-read detection rates were 52.4% with POSLUMA vs 38.1% with piflufolastat. POSLUMA also demonstrated stronger performance in prostate bed and extra-pelvic assessments. No new safety concerns emerged in the comparator cohort.
“These data reinforce POSLUMA’s design to support confident image assessment in anatomically challenging regions,” said Eugene Teoh, MD, Chief Medical Officer, Blue Earth Diagnostics, citing the clinical value of lower urinary activity in early BCR imaging. Phillip Kuo, MD, PhD, FACR, added that the head-to-head evidence “confirms prior studies” and highlights POSLUMA’s potential to improve patient management compared with alternative PSMA PET agents.
POSLUMA (flotufolastat F-18) is FDA-approved for PET imaging of PSMA-positive lesions in men with prostate cancer with suspected recurrence based on elevated PSA. Its favorable pharmacokinetics—particularly low urinary excretion—align with emerging clinical priorities for enhanced lesion conspicuity near the bladder and ureters.
Results were published in European Journal of Nuclear Medicine and Molecular Imaging and presented at the 2026 ASCO Genitourinary Cancers Symposium.
