FORMULA-509: Effects of Abiraterone Acetate Plus Prednisone, Apalutamide on Patient Quality of Life

Updated patient-level data of the FORMULA-509 trial, led by Karen E. Hoffman, MD, MHSc, MPH, and colleagues and presented at the 2024 American Society of Clinical Oncology Genitourinary Cancers Symposium, show that abiraterone acetate plus prednisone (AAP) and apalutamide improved oncologic outcomes without causing a detectable difference in patient-reported hormonal function, fatigue, or mental status.

The FORMULA-509 trial investigated the benefits of prescribing AAP and apalutamide to patients with a prostate-specific antigen (PSA) level higher than 0.5 following radical prostatectomy who received salvage radiation and 6 months of gonadotropin-releasing hormone (GnRH).

Dr. Hoffman and colleagues analyzed the treatment combination’s effects on patient-reported health-related quality of life results.

During the trial, 345 patients received either bicalutamide or AAP and apalutamide following salvage radiation and 6 months of GnRH.

Researchers found that the rate of physician-reported adverse events in the AAP and apalutamide cohort was comparable with previous findings on the safety profile of the combination. In the AAP and apalutamide cohort, 21.8% of patients experienced hypertension, 8.5% experienced diarrhea, and 3.0% were diagnosed with cardiac disorders. In the bicalutamide group, 13.5% of patients reported hypertension, 4.5% experienced diarrhea, and 5.5% reported cardiac disorders.

One year after treatment completion, patients received validated questionaries. Of those who responded, the median age was 64 years, and the median PSA was 0.3. Thirty-five percent reported a Gleason score of 9, while 74% had received pelvic nodal treatment.

Investigators reported no difference between the trial arms in patient-reported EPIC-26 hormonal function domain, EPIC-26 sexual function, fatigue, or cognitive impairment, both at end of treatment and 1 year after treatment completion.

Dr. Hoffman and colleagues concluded that the addition of AAP and apalutamide to salvage radiation plus 6 months of androgen deprivation therapy improved patient outcomes without negatively impacting patient-reported hormonal function, sexual function, fatigue, or mental status at treatment completion or 1 year after treatment end.