Eleni Efstathiou, MD
Invited discussant Eleni Efstathiou, MD, of Houston Methodist Cancer Center and Athens Medical Center, Greece, said that both the STAMPEDE meta-analysis1 and the PEACE-1 trial2 firmly establish the importance of introducing abiraterone acetate earlier in the course of treatment.
“The STAMPEDE investigative group has an impressive track record in practice-changing contributions. Androgen receptor–signaling inhibition is now a key strategy in the treatment of metastatic prostate cancer,” she stated.
“Patients with nonmetastatic high-risk prostate cancer represent an unmet need,” she continued. “With a mere follow-up of 6 years in this trial, obviously we are getting a benefit AAP [abiraterone acetate plus prednisolone] quite early.”
Patient Monitoring Crucial
Dr. Efstathiou noted: “The combination of enzalutamide and AAP plus androgen-deprivation therapy poses unnecessary safety compromises. Detailed monitoring of patients remains of paramount importance. There are otherwise healthy men.”
Limitations of the meta-analysis include the lack of quality-of-life data and data on long-term adverse events, with just 2 years of AAP treatment. “There was no insight from tissue-based analysis, and I think we need to learn more from the diagnostic biopsy molecular signature,” she continued.
These considerations aside, Dr. Efstathiou was impressed by the trial results. “STAMPEDE is truly practice-changing and addresses unmet needs. The survival results are clinically meaningful. The treatments are accessible to the community, but we have to be very vigilant about monitoring,” she stated.
DISCLOSURE: Dr. Efstathiou has received research support from Janssen, Sanofi-Genzyme, Astellas/Medivation, and ORIC Pharmaceuticals; and has served on scientific advisory boards and received honoraria from Janssen, Sanofi-Genzyme, Tomar, Takeda, Bayer, ORIC Pharmaceuticals, Merck, Astellas, Pfizer, Myovant Sciences, and AstraZeneca.
REFERENCES
1. Attard G, Browne LC, Clarke N, et al: Abiraterone acetate plus prednisolone with or without enzalutamide added to androgen deprivation therapy compared to androgen deprivation therapy alone for men with high-risk non-metastatic prostate cancer: Combined analysis from two comparisons in the STAMPEDE platform protocol. ESMO Congress 2021. Abstract LBA4_PR. Presented September 19, 2021.
2. Fizazi K, Galceran JC, Foulon S, et al: A phase III trial with a 2x2 factorial design in men with de novo metastatic castration-sensitive prostate cancer: Overall survival with abiraterone acetate plus prednisone in PEACE-1. ESMO Congress 2021. Abstract LBA5_PR. Presented September 19, 2021.