Molecular Imaging in Focus: Emerging Insights on the PET and SPECT Imaging Agent 61Cu-NU101 for PCa

Could an emerging radiodiagnostic agent offer enhanced detection of metastatic prostate cancer (PCa) and facilitate improved access to PET and SPECT imaging?

In phase 1 research, published in Radiology, the recently patented radiodiagnostic ⁶¹Cu-NU101 (Nuclidium) provided greater detection of malignant lesions in half of the eight-patient cohort than ¹⁸F-piflufolastat (Pylarify, Lantheus) along with lower radiotracer uptake in background tissues and no side effects.

In a recent interview with Diagnostic Imaging, Gary Ulaner, M.D., Ph.D., the primary investigator on the study, cautioned that these are preliminary findings without biopsy proof given the primary emphasis on evaluating safety and dosimetry with ⁶¹Cu-NU101. That said, Dr. Ulaner noted that imaging with ⁶¹Cu-NU101 was very promising.

“ … For preliminary evaluation of efficacy as an imaging agent, (⁶¹Cu-NU101) looked exceptional,” posited Dr. Ulaner, the James and Pamela Muzzy Endowed Chair of Molecular Imaging and Therapy at the Hoag Family Cancer Institute in Irvine, Calif.

(Editor’s note: For related content on prostate cancer imaging, click here.)

Suggesting that ⁶¹Cu-NU101 may offer improved sensitivity for small volume disease, including patients with low PSMA biochemical recurrence, Dr. Ulaner also noted the potentially significant advantage of the ⁶¹Cu-NU101’s 3.3-hour half-life in comparison to 68 minutes with (⁶⁸Ga)Ga-PSMA-11 and 109 minutes with ¹⁸F-piflufolastat.

“There are still areas in the United States that cannot receive some PSMA-targeted agents because there's no production center close to them,” explained Dr. Ulaner, a clinical professor of radiology and cancer biology at the University of Southern California. “With a half-life (of) 3.3 hours with copper 61, with just six or seven production sites, you can cover the entire continental United States.”

(Editor’s note: For related content, see “Comparative Study Shows Merits of PSMA PET/CT for Local Staging of Intermediate and High-Risk PCa,” “Can PET Imaging Predict Treatment Outcomes for the 225Ac-labeled PSMA Radiopharmaceutical in Patients with mCRPC?” and “Can PSMA PET Parameters Help Predict Toxicity and Outcomes in Patients Treated for mCRPC?”)