title: Subsequent Chemotherapy and Treatment Patterns After Abiraterone Acetate in Patients with Metastatic Castration-resistant Prostate Cancer: Post Hoc Analysis of COU-AA-302.
abstract: Treatment patterns for metastatic castration-resistant prostate cancer (mCRPC) have changed substantially in the last few years. In trial COU-AA-302 (chemotherapy-naïve men with mCRPC), abiraterone acetate plus prednisone (AA) significantly improved radiographic progression-free survival and overall survival (OS) when compared to placebo plus prednisone (P).
  
  
  
  This post hoc analysis investigated clinical responses to docetaxel as first subsequent therapy (FST) among patients who progressed following protocol-specified treatment with AA, and characterized subsequent treatment patterns among older (≥75 yr) and younger (<75 yr) patient subgroups.
  
  
  
  Data were collected at the final OS analysis (96% of expected death events). Subsequent therapy data were prospectively collected, while response and discontinuation data were collected retrospectively following discontinuation of the study drug.
  
  
  
  At the discretion of the investigator, 67% (365/546) of patients from the AA arm received subsequent treatment with one or more agents approved for mCRPC.
  
  
  
  Efficacy analysis was performed for patients for whom baseline and at least one post-baseline prostate-specific antigen (PSA) values were available.
  
  
  
  Baseline and at least one post-baseline PSA values were available for 100 AA patients who received docetaxel as FST. While acknowledging the limitations of post hoc analyses, 40% (40/100) of these patients had an unconfirmed ≥50% PSA decline with first subsequent docetaxel therapy, and 27% (27/100) had a confirmed ≥50% PSA decline. The median docetaxel treatment duration among these 100 patients was 4.2 mo. Docetaxel was the most common FST among older and younger patients from each treatment arm. However, 43% (79/185) of older patients who progressed on AA received no subsequent therapy for mCRPC, compared with 17% (60/361) of younger patients.
  
  
  
  Patients with mCRPC who progress with AA treatment may still derive benefit from subsequent docetaxel therapy. These data support further assessment of treatment patterns following AA treatment for mCRPC, particularly among older patients.
  
  
  
  ClinicalTrials.gov NCT00887198.
  
  
  
  Treatment patterns for advanced prostate cancer have changed substantially in the last few years. This additional analysis provides evidence of clinical benefit for subsequent chemotherapy in men with advanced prostate cancer whose disease progressed after treatment with abiraterone acetate. Older patients were less likely to be treated with subsequent therapy.
authors.affiliation: The Institute of Cancer Research and The Royal Marsden Hospital, Sutton, UK. Electronic address: johann.de-bono@icr.ac.uk.
authors.forename: Johann S
authors.initials: JS
authors.lastname: de Bono
authors.affiliation: Harvard Medical School and Massachusetts General Hospital, Boston, MA, USA.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Smith
authors.affiliation: Centre Hospitalier University of Montréal, Montréal, Québec, Canada.
authors.forename: Fred
authors.initials: F
authors.lastname: Saad
authors.affiliation: Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, NY, USA.
authors.forename: Dana E
authors.initials: DE
authors.lastname: Rathkopf
authors.affiliation: Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Peter F A
authors.initials: PFA
authors.lastname: Mulders
authors.affiliation: Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Small
authors.affiliation: Carolina Urologic Research Center, Atlantic Urology Clinics, Myrtle Beach, SC, USA.
authors.forename: Neal D
authors.initials: ND
authors.lastname: Shore
authors.affiliation: Institut Gustave Roussy, University of Paris Sud, Villejuif, France.
authors.forename: Karim
authors.initials: K
authors.lastname: Fizazi
authors.affiliation: Janssen Research & Development, Beerse, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: De Porre
authors.affiliation: Janssen Research & Development, San Diego, CA, USA.
authors.forename: Thian
authors.initials: T
authors.lastname: Kheoh
authors.affiliation: Johnson & Johnson Medical China, Shanghai, China.
authors.forename: Jinhui
authors.initials: J
authors.lastname: Li
authors.affiliation: Janssen Global Services, Raritan, NJ, USA.
authors.forename: Mary B
authors.initials: MB
authors.lastname: Todd
authors.affiliation: Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA.
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Ryan
authors.affiliation: University of Colorado Cancer Center, Aurora, CO, USA.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Flaig
mesh_terms: D000069501:Abiraterone Acetate / Q000008:administration & dosage; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002277:Carcinoma / Q000188:drug therapy* / Q000556:secondary; D018572:Disease-Free Survival; D000077143:Docetaxel; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010818:Practice Patterns, Physicians'; D011241:Prednisone / Q000008:administration & dosage; D064129:Prostatic Neoplasms, Castration-Resistant / Q000188:drug therapy* / Q000473:pathology; D015996:Survival Rate; D043823:Taxoids / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D043823:Taxoids; D000077143:Docetaxel; D000069501:Abiraterone Acetate; D011241:Prednisone
keywords: Abiraterone acetate; Docetaxel; Elderly; Metastatic castration-resistant prostate cancer; Subsequent therapy; Treatment patterns