Positive Results from the Use of 177Lu-PNT2002 Treatment Followed by SBRT Radiotherapy

Researchers at UCLA found that adding a special radioactive drug before targeted radiation helped men with recurrent prostate cancer stay cancer-free much longer than with radiation alone.

The treatment targets PSMA, a protein abundantly expressed on prostate cancer cells. The radioactive drug 177Lu- PNT2002 binds to PSMA and delivers radiation directly to cancer cells. This allows doctors to treat not only tumors visible on scans, but also tiny cancer spots too small to detect.

The study , called the LUNAR trial, included 92 men with prostate cancer that had returned in only a few small areas. They were randomly split into two groups: one received radiation alone, and the other received the radioactive drug first, then radiation.

The main finding was that men who received the drug plus radiation remained free of cancer progression for a median of 17.6 months,

compared to 7.4 months with radiation alone. The combined treatment also reduced the risk of cancer progression, need for hormone therapy , or death by 63%.

Another key result was that the combined treatment delayed the need for hormone therapy for about 24.3 months, versus 14.1 months with radiation alone. This delay can greatly improve the quality of life.

Researchers also studied which patients benefit most. Those with stronger immune responses after treatment tended to do better. A group of genes related to immune function and DNA repair may help predict the risk of cancer progression.

While the new treatment extended remission, 64% of patients still experienced cancer progression, highlighting ongoing challenges. However, side effects from the radioactive drug were minimal, with no significant increase in symptoms.

The researchers say this study matters because it shows that radioligand therapy , usually used in late-stage cancer, can also help earlier in the disease. They plan to keep studying this treatment approach to achieve better results and better understand what happens in the long run.

Overall, the study demonstrates that combining PSMA-targeted radioligand therapy with precise radiation extends progression-free survival and postpones quality-of-life-impacting treatments for men with recurring prostate cancer.

UCLA Health, November 2025