¹⁷⁷Lu-Prostate-Specific Membrane Antigen Ligand After ²²³Ra Treatment in Men with Bone-Metastatic Castration-Resistant Prostate Cancer: Real-World Clinical Experience.

Abstract

We analyzed real-world clinical outcomes of sequential α-/β-emitter therapy for metastatic castration-resistant prostate cancer (mCRPC). <b>Methods:</b> We assessed safety and overall survival in 26 patients who received ¹⁷⁷Lu-prostate-specific membrane antigen ligand (¹⁷⁷Lu-PSMA) after ²²³Ra in the ongoing noninterventional REASSURE study (²²³Ra α-Emitter Agent in Nonintervention Safety Study in mCRPC Population for Long-Term Evaluation; NCT02141438). <b>Results:</b> Patients received ²²³Ra for a median of 6 injections and subsequent ¹⁷⁷Lu-PSMA for a median of 3.5 mo (≥ the fourth therapy in 69%). The median time between ²²³Ra and ¹⁷⁷Lu-PSMA treatment was 8 mo (range, 1-31 mo). Grade 3 hematologic events occurred in 9 of 26 patients (during or after ¹⁷⁷Lu-PSMA treatment in 5/9 patients; 8/9 patients had also received docetaxel). Median overall survival was 28.0 mo from the ²²³Ra start and 13.2 mo from the ¹⁷⁷Lu-PSMA start. <b>Conclusion:</b> Although the small sample size precludes definitive conclusions, these preliminary data, especially the ¹⁷⁷Lu-PSMA treatment duration, suggest that the use of ¹⁷⁷Lu-PSMA after ²²³Ra is feasible in this real-world setting.