Safety and antitumor activity of apalutamide (ARN-509) in metastatic castration-resistant prostate cancer with and without prior abiraterone acetate and prednisone Journal Article


Authors: Rathkopf, D. E.; Antonarakis, E. S.; Shore, N. D.; Tutrone, R. F.; Alumkal, J. J.; Ryan, C. J.; Saleh, M.; Hauke, R. J.; Bandekar, R.; Maneval, E. C.; de Boer, C. J.; Yu, M. K.; Scher, H. I.
Article Title: Safety and antitumor activity of apalutamide (ARN-509) in metastatic castration-resistant prostate cancer with and without prior abiraterone acetate and prednisone
Abstract: Purpose: To evaluate the efficacy of apalutamide before or after treatment with abiraterone acetate and prednisone (AAP) in patients with progressive metastatic castration-resistant prostate cancer (mCRPC). Experimental Design: Two cohorts were studied: AAP-naïve and post-AAP patients who had received ≥6 months of AAP. Patients had progressive mCRPC per rising prostate-specific antigen (PSA) and/or imaging, without prior chemotherapy exposure. All received apalutamide 240 mg/day. Primary endpoint was ≥50% decline in 12-week PSA according to Prostate Cancer Working Group 2 criteria. Secondary endpoints included time to PSA progression and time on treatment. Results: Forty-six patients enrolled in the AAP-naïve (n ¼ 25) and post-AAP (n ¼ 21) cohorts. The 12-week PSA response rate was 88% (22/25) and 22% (4/18), median time to PSA progression was 18.2 months [95% confidence interval (CI), 8.3 months–not reached) and 3.7 months (95% CI, 2.8–5.6 months), and median time on treatment 21 months (range, 2.6–37.5) and 4.9 months (range, 1.3–23.2), for the AAP-naïve and post-AAP cohorts, respectively. Eighty percent (95% CI, 59–93) and 64% (95% CI, 43–82) of AAP-naïve and 43% (95% CI, 22–66) and 10% (95% CI, 1–30) of post-AAP patients remained on treatment for 6þ and 12þ months, respectively. Common treatment-emergent adverse events in both cohorts were grade 1 or 2 fatigue, diarrhea, nausea, and abdominal pain. Conclusions: Apalutamide was safe, well tolerated, and demonstrated clinical activity in mCRPC, with 80% of AAP-naïve and 43% of post-AAP patients, remaining on treatment for 6 months or longer. ©2017 AACR.
Journal Title: Clinical Cancer Research
Volume: 23
Issue: 14
ISSN: 1078-0432
Publisher: American Association for Cancer Research  
Date Published: 2017-07-15
Start Page: 3544
End Page: 3551
Language: English
DOI: 10.1158/1078-0432.ccr-16-2509
PROVIDER: scopus
PMCID: PMC5543693
PUBMED: 28213364
DOI/URL:
Notes: Article -- Export Date: 2 August 2017 -- Source: Scopus
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MSK Authors
  1. Dana Elizabeth Rathkopf
    245 Rathkopf
  2. Howard Scher
    1111 Scher