We are seeing more and more novel therapies being developed to treat castrate resistant metastatic prostate cancer (mCRPC). One such therapy involves theranostic (individualized therapies for various diseases, and to combine diagnostic and therapeutic capabilities into a single agent) concepts using radiolabeled ligands of the prostate-specific membrane antigen (PSMA).

In a recent study, designed to evaluate tumor response, adverse effects, and survival in men with castrate resistant prostate cancer who had exhausted all other potential approved therapies, evaluated the novel radioligand therapy with Lu-PSMA-617.

Fifty therapies using Lu-PSMA-617 were performed in 28 consecutive men with mCRPC. Data were retrospectively analyzed with focus on response, safety, and survival. The median overall survival was compared with that of a recent historical patient cohort treated with best supportive care prior to availability of Lu-PSMA-617.

Some PSA decline occurred in 59% and 75% of the subject men after 1 and 2 therapies. They also found a PSA decline of 50% or greater occurred in 32% and 50% of the men. The therapies were well tolerated with minimal toxicities. The researchers estimated median survival was 29.4 weeks which is  significantly longer than survival in the historical best supportive care group which was calculated to be only 19.7 weeks.

Results from 50 therapies show that radioligand therapy with Lu-PSMA-617 is effective and well tolerated and seems to increase overall survival. Despite the fact that we now need a randomized controlled prospective study to confirm these results it is inspiring to know that our scientists are hard at work trying to extend our lives.

Clinical nuclear medicine. 2016 Apr 15 [Epub ahead of print]

Kambiz Rahbar, Axel Bode, Matthias Weckesser, Nemanja Avramovic, Michael Claesener, Lars Stegger, Martin Bögemann

From the Departments of *Nuclear Medicine and †Urology, University Hospital Münster, Münster, Germany.

PubMed http://www.ncbi.nlm.nih.gov/pubmed/27088387