GU Cancers 2023 | FORMULA-509 rationale + trial design: the addition of AAP + apa post-radical prostatectomy

Paul L. Nguyen, MD, Dana-Farber Cancer Institute, Boston, MA, shares the rational and trial design of the Phase II randomized FORMULA-509 (NCT03141671) trial assessing post-operative salvage radiotherapy and 6 months of GnRH agonist with or without abiraterone acetate/prednisone and apalutamide post-radical prostatectomy in patients with a rising PSA after radical prostatectomy. The standard treatment for patients with prostate cancer is usually salvage radiation with 6 months of androgen deprivation therapy (ADT). The trial assessed whether adding 6 months of apalutamide and abiraterone could improve outcomes compared to the standard of 6 months of bicalutamide with 6 months of ADT. Patients had PSA≥0.1 post-radical prostatectomy and one or more unfavorable features (Gleason 8-10, PSA more than 0.5 pT3/T4, pN1 or radiographic N1, PSA doubling time less than 10 months, negative margins, persistent PSA, gross local/regional disease, or Decipher High Risk) and were stratified by PSA level and node positivity. This interview took place at the ASCO GU Cancers Symposium 2023 in San Francisco, CA.