61Cu-NU101 is a new PSMA-targeted PET/SPECT tracer for prostate cancer that showed promise in phase 1, detecting more lesions than 18F-piflufolastat (Pylarify) in half of the 8 patients studied, with lower background uptake and no side effects.
The key advantage is its 3.3-hour half-life, compared to 68 minutes for 68Ga-PSMA-11 and 109 minutes for 18F-piflufolastat. This means fewer production sites can cover, for example, the entire continental U.S., expanding access to PSMA imaging in areas that currently can’t receive short-lived tracers.
Because of that longer half-life, you can image at 4 hours post-injection instead of ~1 hour, and the number of detected lesions increases up to that point. This delayed imaging helps detect small metastases that standard tracers miss.
61Cu-NU101 also detected additional lesions in patients with small-volume disease and low PSMA expression,tumors that are typically harder to visualize with current PSMA tracers.
The tracer enables true theranostics with 67Cu, using the same NU101 ligand labeled with 61Cu for imaging or 67Cu for therapy. The key advantage is that if 61Cu finds more lesions, including micrometastases, then 67Cu can treat all of them.