Next-Generation Imaging

Daniel Spratt, MD, highlights the evolving paradigm of PET-based imaging agents in prostate cancer, with a focus on the impact of PSMA-PET imaging.

In total, the phase 1/2 PRESERVE-006 trial is expected to enroll 144 patients across 20 clinical trial sites in the US.

All patients treated with 177Lu-rhPSMA-10.1 had reductions in their PSA levels from the start of treatment and none experienced a serious treatment-related adverse event.

"What we found was that the obedience to the upgrading criteria of PI-RADS as they are today resulted in a better overall outcome for all the patients that were included in the study," says Leonardo Kayat Bittencourt, MD, PhD.

In patients where SOC imaging was unable to detect any lesions, 64Cu-SAR-bisPSMA was able to identify lesions in approximately 60% of patients on same-day imaging and up to 80% on next-day imaging.

“I think that having the clinical context such as the PSA, the Gleason score, the other features that assess the aggressiveness of the disease can really help with some of these subtle findings that can be found on PET imaging,” says Daniel Spratt, MD.

“Treatment based on visualization of 18F-flotufolastat–avid lesions may facilitate optimal targeting of recurrence sites and avoid futile salvage therapy,” said Przemyslaw Twardowski, MD.

The conference explored the current and future use of PSMA-PET imaging and PSMA radioligand therapy to improve the clinical care of patients with prostate cancer.

PSMA uptake in the prostatic midline is often linked with urine stagnation in the prostatic urethra and can lead to misinterpretation on PSMA-PET/CT,” the authors wrote. “Using post-void MRIs may help reduce false positives.”

“99mTc‐PSMA-SPECT/CT is useful in the primary diagnosis of prostate cancer,” the authors wrote.

“This data supports the clinical benefit of 177Lu-PSMA-617 in real-world clinical practice,” the researchers wrote in their poster conclusion.

“Prostatic extracellular vesicles represent a promising biomarker with the potential for reduction of false positive rate in men with elevated PSA following mpMRI,” the authors wrote.

PSMA-PET imaging has successfully disrupted the prostate cancer paradigm and experts agree that unleashing the full potential of this breakthrough requires a multidisciplinary approach.

"What we saw was it that there were a significant number of patients that did change their management based on the findings. Of those patients, 88% of them changed because of a positive test," says Benjamin H. Lowentritt, MD, FACS.

Validation testing suggested the combined model would prevent unnecessary systematic prostate biopsies in over 40% of study patients.

Data showed a similar incidence of TEAEs and TRAEs between cycles 1-4 and cycles 5-6 of treatment with 177Lu-PSMA-617.

The conference, “PSMA PET and RLT: Present and Future," is taking place online and in-person in San Francisco on January 18 and 19, 2024.

"While preliminary in nature, these data provide a compelling rationale for consideration of PSMA PET as an alternative staging modality at the time of primary diagnosis," wrote the authors.

“To our knowledge, this is the largest investigation of the antitumor effect and toxicity of 225Ac-PSMA radioligand therapy in mCRPC,” the authors wrote.

The facility will increase the production capacity of 177Lu-PSMA-617 to 250,000 doses in 2024 and beyond.

Data from the phase 2 TheraP trial showed that 177Lu-PSMA-617 induced comparable overall survival outcomes as cabazitaxel in patients with metastatic castration-resistant prostate cancer who progressed after receiving docetaxel.

As the year comes to a close, we revisit some of this year’s top content on next-generation imaging agents in urology.

Findings from the research showed that 68Ga-RM2 PET/MRI had an 85.2% sensitivity rate for diagnosing biochemical recurrence of prostate cancer.

Overall, 177Lu-PNT2002 demonstrated a median radiographic progression-free survival of 9.5 months, compared with 6.0 months among patients who were treated with an ARPI.

The BLA submission is supported by findings from the phase 3 ZIRCON study, which demonstrated high specificity and sensitivity of the agent for PET/CT imaging of ccRCC.

225Ac-PSMA-J591 showed promising efficacy in mCRPC metastatic sites that are commonly resistant to 177Lu-PSMA-617.

Utilizing a deep learning-based AI algorithm to differentiate between diagnostic and non-diagnostic quality of prostate MRI facilitated a 10% higher specificity rate for diagnosing extraprostatic extension on multiparametric MRI, according to research presented at the 2023 RSNA Annual Meeting.

The patents apply exclusively to the Ga-68 HBED-PSMA-11 production kit (Locametz), developed by Advance Accelerator Applications.

According to Clarity Pharmaceuticals, the final results are intended to support an application to the FDA for approval of 64Cu-SAR-bisPSMA for imaging in patients with prostate cancer.

No dose-limiting toxicities were observed among the initial 3 patients in cohort 3, and no patients experienced adverse events related to 64Cu-SAR-bisPSMA.