STREAM. Enzalutamide + ADT with Salvage Radiation in high-risk PSA-recurrent PCa after RP

[pjoshea13]

New study results from the STREAM trial.

"... a three-center prospective phase 2 single-arm trial ... of men with Gleason 7-10 PC and PSA recurrence within 4 yr of RP {prostatectomy} ranging from 0.2 to 4.0 ng/dl, no prior hormonal therapy, and no radiographic evidence of metastases. We enrolled 38 men; 37 completed therapy ..."

"Six months of ADT with 160 mg/d enzalutamide and 66 Gy RT to the prostate bed."

"The primary endpoint of 2-yr {progression-free survival} was 65% ... versus 51% ... in a trial of men with similar eligibility treated with salvage RT and adjuvant docetaxel."

"The 3-yr {progression-free survival} was 53%."

"Salvage RT with enzalutamide and ADT following RP for men with PSA recurrent high-risk PC is safe and demonstrates encouraging efficacy, warranting prospective controlled phase 3 trials of ADT with or without potent androgen receptor inhibition in this curative-intent {!!!} setting."

***

Implies that improved progression-free survival translates to improved overall survival. However, the addition of 6 months of XTANDI may change the nature of surviving PCa cells. Half of the men progressed within 3 years. How did prior XTANDI use affect their overall survival?

-Patrick

[1] pubmed.ncbi.nlm.nih.gov/320...

[AlooGobi]

Seems like Ravi Madan at the NIH answered that question this week -

jitc.bmj.com/content/9/3/e0...

… concluding that short course Enza of 3 months without / adt resulted in similar bfs the second go around - perhaps 10% less than the first hit. Just short of a year - some nice year + responders here too.

Note conventional imaging here. Also No mdt. Can’t trust “non-metastatic” if psma will detect mets in majority of guys with levels over .5… I think Madan himself throws out that same caveat.