Real-World Study of 177Lu-PSMA-617 in Patients With mCRPC Gives Treatment Use, Outcome Insights

Lu 177 vipivotide tetraxetan (177Lu-PSMA-617) was approved by the US Food and Drug Administration in 2022 for the treatment of patients with prostate-specific membrane antigen (PSMA) positive metastatic castration resistant prostate cancer (mCRPC) who have received prior treatment with androgen receptor pathway inhibition (ARPI) and taxane-based chemotherapy.

As the utilization of 177Lu-PSMA-617 in patients is growing, a real-world study presented at the 2024 American Society of Clinical Oncology Genitourinary Cancers Symposium by Xiao X. Wei, MD, examined the patient outcomes of early adopters of 177Lu-PSMA-617, including their clinical characteristics, treatment use, and clinical outcomes. The study is the first large-scale report of patients in the United States treated with 177Lu-PSMA-617.

The study analyzed 1710 patients in the United States with mCRPC who were treated with 177Lu-PSMA-617 between March 2022 and June 2023. Clinical characteristics, treatment use, and prior treatment use was analyzed. A subset of patients with available prostate-specific antigen (PSA) rates were also examined for PSA response after initiation of 177Lu-PSMA-617.

Baseline PSA was defined as the closest PSA value within 90 days prior to or during initial 177Lu-PSMA-617 treatment. Post-treatment PSA response was defined as the lowest PSA value ≥28 days after the index date, and patients with ≥ 50%, ≥80% and ≥90% PSA reductions were reported.

Out of the total patient cohort, 1447 (84.6%) patients experienced bone metastasis, 575 (33.6%) had visceral metastasis, and 128 (7.5%) had liver metastasis. Lymph node-only metastasis occurred in 59 (3.5%) patients.

Before undergoing treatment with 177Lu-PSMA-617, 83.4% patients had used prior ARPI and/or taxane chemotherapy, while 98% patients had used other systemic therapies. A sub-analysis of 159 (9.3%) patients with available PSA values, the median PSA at baseline before initiation of 177Lu-PSMA-617 was 61 ng/ml. Among these patients, 53.5%, 29.6% and 22.6% had PSA reductions of ≥50%, ≥80% and ≥90%, respectively, while on treatment.

The clinical characteristics and PSA responses observed are similar to those from the VISION clinical trial, demonstrating benefit with 177Lu-PSMA-617. Follow-up is needed to understand the further long-term outcomes of 177Lu-PSMA-617 in patients.