Telix ProstACT Global Phase 3 Part 1 ASCO 2026: PSMA-Targeted Lutetium-177 Rosopatamab Radio-ADC Meets Primary Safety Objectives in PSMA-Positive mCRPC
Telix Pharmaceuticals reported ProstACT Global Phase 3 Part 1 data at ASCO 2026 as a late-breaking presentation. TLX591-Tx (lutetium-177 rosopatamab tetraxetan) — a PSMA-targeted lutetium radio-antibody-drug conjugate — met its primary safety objectives in the safety and dosimetry lead-in, demonstrating an acceptable tolerability profile with no new safety signals when combined with enzalutamide (Xtandi), abiraterone (Zytiga), or followed by docetaxel in PSMA-positive metastatic castration-resistant prostate cancer (mCRPC). ProstACT Global is an international Phase 3 trial evaluating TLX591-Tx plus standard of care versus standard of care alone. The drug sits in the PSMA-targeted radioligand class alongside Novartis's approved Pluvicto (lutetium-177 PSMA-617, a peptide-based radioligand), but uses an antibody rather than a small-molecule peptide as the targeting vector. The PSMA radioligand field — Pluvicto, ProstACT, plus the Aktis AKY-2519 B7-H3 miniprotein radioconjugate covered earlier this week — is one of the fastest-growing targeted-conjugate categories in oncology.