Abiraterone in Elderly Chemotherapy-Naive Patients with mCRPC

Charles J. Ryan, MD. - Journal Club: Efficacy and Safety of Abiraterone Acetate in Elderly Chemotherapy-Naive Patients with Metastatic Castration-Resistant Prostate Cancer 

Article Abstract:

Purpose: Metastatic castration-resistant prostate cancer primarily affects elderly men. In
this post hoc analysis we investigated the safety and efficacy of abiraterone acetate in
elderly (≥75 years) and younger (<75 years) patient subgroups at the prespecified
interim analysis (55% of total overall survival [OS] events) for the COU-AA-302 trial.

Materials and Methods: Patients were stratified and randomized 1:1 to abiraterone
acetate 1,000 mg plus prednisone/prednisolone 5 mg bid (abiraterone-prednisone) vs
placebo plus prednisone/prednisolone 5 mg bid (prednisone alone). Co-primary end
points were radiographic progression-free survival (rPFS) and OS. Median time to event
and hazard ratio (HR) were estimated using Kaplan-Meier method and Cox model,
respectively.

Results: Elderly patients (n=350) treated with abiraterone-prednisone had significant
improvements in OS and rPFS vs prednisone alone (HR=0.71 [95% CI 0.53–0.96] and
HR=0.63 [95% CI 0.48–0.83], respectively), similar to younger patients (n=738, HR=0.81
[95% CI 0.63–1.03] and HR=0.49 [95% CI 0.40–0.59], respectively). All secondary end
points favored the abiraterone-prednisone arm for both age subgroups. Specific adverse
events with abiraterone-prednisone were similar between age subgroups. Elderly
patients in both treatment arms had higher rates of fluid retention and cardiac disorders
than younger patients, although rates of dose reduction or treatment interruptions due to
adverse events were low in both age subgroups.

Conclusions: Abiraterone acetate demonstrated clinical benefit and was well tolerated
in both elderly and younger men with chemotherapy-naïve metastatic castrationresistant
prostate cancer, thus supporting it as a treatment option for elderly patients
who may not tolerate other therapies with greater toxicity.

Article Title: Efficacy and Safety of Abiraterone Acetate in Elderly (75 Years or Older) Chemotherapy Naïve Patients with Metastatic Castration Resistant Prostate Cancer.

Smith MR, Rathkopf DE, Mulders PF, Carles J, Van Poppel H, Li J, Kheoh T, Griffin TW, Molina A, Ryan CJ.

Presenting Author: Charles J. Ryan, MD
Professor of Clinical Medicine
Division of Hematology / Oncology
Helen Diller Family Comprehensive Cancer Center
University of California, San Francisco

Biography: Charles J. Ryan, MD is a Professor of Medicine in the Division of Hematology / Oncology at the Helen Diller Family Comprehensive Cancer Center at the University of California, San Francisco (UCSF) where he is the leader of the Genitourinary Medical Oncology Program. He received his MD from the University of Wisconsin in Madison and completed his residency in internal medicine at the University of Wisconsin Hospital and Clinics, where he also served as Chief Resident. He completed a fellowship in medical oncology in the Department of Medicine at Memorial Sloan-Kettering Cancer Center and the Joan and Sanford I. Weill Medical College of Cornell University in New York.

Dr. Ryan's clinical practice focuses predominantly on advanced prostate cancer, as well as germ cell (testicular) tumors and other malignancies of the genitourinary tract.

His clinical and research work centers on the design and conduct of clinical trials of novel therapies for advanced prostate cancer, specifically secondary hormonal therapies targeting adrenal androgen signaling, insulin growth factor inhibitors, androgen receptor targeted therapy and chemotherapy.  In addition to clinical trials, Dr. Ryan collaborates with many laboratories researching the role of the androgen receptor and other signaling mechanisms in prostate cancer patients.

Dr. Ryan is a member of several honor societies and is the recipient of a Leadership and Service Award and the John Kimberly Curtis Award from the University of Wisconsin Medical School. He received the American College of Physicians/ American Society of Internal Medicine Evergreen Award in 2000 and the American Society of Clinical Oncology Merit Award and Cancer And Leukemia Group B: Young Investigator Award, both in 2003. He was awarded the Don