Tb-161 PSMA-I&T (β + Auger RLT) achieves 70% PSA50 response in post-taxane mCRPC

In the single-arm Phase I/II VIOLET trial (NCT05521412), 30 PSMA-PET–positive mCRPC patients previously treated with taxane ± ARPI received up to six Q6W cycles of [^161Tb]Tb-PSMA-I&T (4.4-7.4 GBq; 3 + 3 escalation); no dose-limiting toxicities occurred and 7.4 GBq was recommended for Phase II. Grade ≥3 TRAEs were rare (lymphopenia and pain flare only), with no treatment-related deaths. PSA50 and PSA90 responses reached 70% and 40%, respectively, while median PSA-PFS and rPFS were 9.0 mo and 11.1 mo—numerically higher than the 46% PSA50 and 8.7 mo rPFS reported for Lu-177 PSMA-617 in VISION.