Abiraterone Plus Prednisone in Metastatic, Castration-Sensitive Prostate Cancer



Title: Abiraterone plus Prednisone in Metastatic, Castration-Sensitive Prostate Cancer

Fizazi, K. et al.


 

What You Need to Know:

For patients with newly diagnosed, metastatic, castration-sensitive prostate cancer, adding abiraterone acetate and prednisone to androgen-deprivation therapy increased both overall as well as radiographic progression-free survival.

Trial Design:

  • Double-blind, placebo-controlled phase 3 study evaluated the benefits of adding abiraterone acetate and prednisone to androgen-deprivation therapy
  • 1199 men with newly diagnosed, metastatic, castration-sensitive prostate cancer were randomized to receive 1000mg abiraterone acetate and 5mg prednisone daily or placebo, in addition to androgen-deprivation therapy
  • Primary endpoints: overall survival, radiographic progression-free survival
  • Secondary endpoints: “time to the next “skeletal-related event” (described here as a “symptomatic skeletal event,” which was defined as a clinical or pathological fracture, spinal-cord compression, palliative radiation to bone, or surgery involving bone), time to progression with respect to prostate-specific antigen (PSA) level on the basis of Prostate Cancer Working Group 2 criteria, time to the next therapy for prostate cancer, time to initiation of chemotherapy, and time to pain progression”

Key Outcomes:

  • At a median follow-up of 30.4 months, median overall survival was longer in abiraterone patients vs placebo patients (not reached vs 34.7 months) (HR for death: 0.62; 95% CI: 0.51, 0.76; P<0.001)
  • Median length of radiographic progression-free survival: 33.0 months for abiraterone patients vs 14.8 months for placebo patients (HR for disease progression or death: 0.47; 95% CI: 0.39, 0.55; P<0.001)
  • Secondary endpoints: for all endpoints analyzed, better outcomes were observed in the abiraterone group vs placebo group
  • Due to these findings, the trial was unblinded and crossover from placebo to abiraterone was executed
  • Higher rates of grade 3 hypertension and hypokalemia were reported for abiraterone patients