Dr Berchuck on Next Steps for Evaluating a Novel Liquid Biopsy for PSMA in mCRPC

Jacob E. Berchuck, MD, assistant professor, Department of Hematology and Medical Oncology; medical oncologist, genitourinary cancers, Winship Cancer Institute, Emory University, shares potential next steps to evaluate and validate the correlation between a novel epigenomic liquid biopsy–predicted PSMA expression with the PSMA PET scans in metastatic castration-resistant prostate cancer (mCRPC).

In a study that investigated the use of a novel liquid biopsy assay to detect tumor PSMA expression, Berchuck notes that there are ongoing efforts to build on the work that was presented at the 2024 ESMO Congress. Among patients with mCRPC undergoing PET scans in the study, he explains that additional plasma samples were collected to determine the correlation between a novel epigenomic liquid biopsy–predicted PSMA expression with the PSMA PET scan.

The study included 29 patients with mCRPC who underwent PSMA PET scan and provided a sample to use in the novel liquid biopsy assay. Patients were then screened for eligibility for lutetium Lu 177 vipivotide tetraxetan treatment.

Berchuck says he looks forward to furthering research regarding those who went on to receive lutetium Lu 177 vipivotide tetraxetan treatment. He explains that plasma samples are available from a larger prospective cohort taken at the time of lutetium Lu 177 vipivotide tetraxetan initiation. Based on the early data, cfDNA–predicted PSMA expression has shown a strong correlation with outcomes associated with lutetium Lu 177 vipivotide tetraxetan. He emphasizes that these results could indicate that cfDNA–predicted PSMA expression may be a potentially useful biomarker to help establish whether patients are more likely to have response to the treatment, and where to prioritize other prostate cancer therapies or clinical trials to improve patient outcomes.

Another area for next steps includes determining how tumors might evolve and develop resistance to lutetium Lu 177 vipivotide tetraxetan, Berchuck says. After collecting plasma samples from patients at the time of disease progression on lutetium Lu 177 vipivotide tetraxetan, he notes that using the epigenomic liquid biopsy assay may help identify possible treatment resistance.