TY - JOUR
T1 - Safety of concomitant therapy with radium-223 and abiraterone or enzalutamide in a real-world population
AU - Zhao, Hanson
AU - Howard, Lauren E.
AU - De Hoedt, Amanda M.
AU - Terris, Martha K.
AU - Amling, Christopher L.
AU - Kane, Christopher J.
AU - Cooperberg, Matthew R.
AU - Aronson, William J.
AU - Klaassen, Zachary
AU - Polascik, Thomas J.
AU - Vidal, Adriana C.
AU - Freedland, Stephen J.
N1 - Funding Information:
This study was conducted with the support of Bayer Pharmaceuticals. Adriana Vidal was supported by a Research Scholar Grant, RSG-18-018-01-CPHPS, from the American Cancer Society. William Aronson was supported by NIH Grant R01 CA231219.
Publisher Copyright:
© 2021 Wiley Periodicals LLC
PY - 2021/5/15
Y1 - 2021/5/15
N2 - Background: Real-world utilization and outcomes of combination therapy for men with metastatic castrate-resistant prostate cancer (mCRPC) are largely unknown. We evaluated the overall survival (OS) and skeletal-related events (SREs) among men who received radium-223 with or without concomitant abiraterone or enzalutamide in the Veterans Affairs (VA) Health System. Methods: We reviewed charts of all mCRPC patients who received radium-223 in the VA from January 2013 to September 2017. We used Cox models to test the association between concomitant therapy versus radium-223 alone on OS and SRE. Sensitivity analyses were performed for concomitant use of denosumab/bisphosphonates. Results: Three hundred and eighteen patients treated with radium-223 were identified; 116/318 (37%) received concomitant abiraterone/enzalutamide. Two hundred and seventy-seven (87%) patients died during follow-up. Patients who received concomitant therapy were younger at radium-223 initiation (median age 68 vs. 70, p =.027) and had a longer follow-up (median 29.5 vs. 17.9 months, p =.030). There was no OS benefit for those on concomitant therapy (hazard ratio [HR]: 0.87, 95% confidence interval [CI]: 0.67–1.12, p =.28). There was a trend for an increased SRE risk for patients on concomitant therapy (HR: 1.87, 95% CI: 0.96–3.61, p =.066), but this was not significant. When analyses were limited to men using bone heath agents, similar results were seen for OS (HR: 0.86, 95% CI 0.64–1.15, p =.30) and SRE (HR: 2.36, 95% CI: 0.94–5.94, p =.068). Conclusions: Despite the common use of concomitant therapy in this real-world study, there was no difference in OS among mCRPC patients. A nonsignificant increased SRE risk was observed. Further work needs to evaluate the optimal sequence, timing, and safety of combination therapies.
AB - Background: Real-world utilization and outcomes of combination therapy for men with metastatic castrate-resistant prostate cancer (mCRPC) are largely unknown. We evaluated the overall survival (OS) and skeletal-related events (SREs) among men who received radium-223 with or without concomitant abiraterone or enzalutamide in the Veterans Affairs (VA) Health System. Methods: We reviewed charts of all mCRPC patients who received radium-223 in the VA from January 2013 to September 2017. We used Cox models to test the association between concomitant therapy versus radium-223 alone on OS and SRE. Sensitivity analyses were performed for concomitant use of denosumab/bisphosphonates. Results: Three hundred and eighteen patients treated with radium-223 were identified; 116/318 (37%) received concomitant abiraterone/enzalutamide. Two hundred and seventy-seven (87%) patients died during follow-up. Patients who received concomitant therapy were younger at radium-223 initiation (median age 68 vs. 70, p =.027) and had a longer follow-up (median 29.5 vs. 17.9 months, p =.030). There was no OS benefit for those on concomitant therapy (hazard ratio [HR]: 0.87, 95% confidence interval [CI]: 0.67–1.12, p =.28). There was a trend for an increased SRE risk for patients on concomitant therapy (HR: 1.87, 95% CI: 0.96–3.61, p =.066), but this was not significant. When analyses were limited to men using bone heath agents, similar results were seen for OS (HR: 0.86, 95% CI 0.64–1.15, p =.30) and SRE (HR: 2.36, 95% CI: 0.94–5.94, p =.068). Conclusions: Despite the common use of concomitant therapy in this real-world study, there was no difference in OS among mCRPC patients. A nonsignificant increased SRE risk was observed. Further work needs to evaluate the optimal sequence, timing, and safety of combination therapies.
KW - abiraterone
KW - concomitant therapy
KW - enzalutamide
KW - metastatic prostate cancer
KW - radium-223
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U2 - 10.1002/pros.24115
DO - 10.1002/pros.24115
M3 - Article
C2 - 33705584
AN - SCOPUS:85102283007
SN - 0270-4137
VL - 81
SP - 390
EP - 397
JO - Prostate
JF - Prostate
IS - 7
ER -