The RaLu study demonstrated that the sequence Radium-Lutetium is safe, with outcomes consistent with other published reports. The safety profile of Lu-177 PSMA was similar regardless of the time interval between Ra-223 and Lu-177 PSMA treatments or the use of taxane chemotherapy prior to Lu-177 PSMA. The most common adverse events were anemia and thrombocytopenia.

While the primary endpoint of the RaLu study was safety, it also found that the efficacy of Lu-177 PSMA was similar across various subgroups. This suggests that the order of treatment and timing intervals between Ra-223 and Lu-177 PSMA may not significantly impact survival outcomes.

The experts discussed the relevance of these findings in the context of other recent clinical trials. The PEACE-3 trial demonstrated the efficacy of combining Ra-223 with enzalutamide as a first-line therapy for mCRPC, significantly improving both radiographic progression-free survival (rPFS) and overall survival (OS) compared to enzalutamide alone. Both RaLu and PEACE-3 trials suggest a potential role for radiopharmaceuticals in the earlier stages of mCRPC management.
The ongoing AlphaBet trial is investigating the feasibility and efficacy of administering Ra-223 and Lu-177 PSMA simultaneously. The experts emphasized that further research, including investigations into the reverse sequencing (LuRa), is necessary to determine the optimal use of radiopharmaceuticals in mCRPC treatment.

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