Abiraterone vs. docetaxel for metastatic hormone-sensitive prostate cancer: A microsimulation model

  • Amanda E. Hird Division of Urology, Sunnybrook Health Sciences Center, Toronto, Ontario; Institute for Health Policy, Management, and Evaluation, University of Toronto
  • Diana E. Magee Division of Urology, Princess Margaret Hospital, University Health Network, Toronto, Ontario; Institute for Health Policy, Management, and Evaluation, University of Toronto
  • Douglas C. Cheung Division of Urology, Princess Margaret Hospital, University Health Network, Toronto, Ontario; Institute for Health Policy, Management, and Evaluation, University of Toronto
  • Rano Matta Division of Urology, Sunnybrook Health Sciences Center, Toronto, Ontario; Institute for Health Policy, Management, and Evaluation, University of Toronto
  • Girish S. Kulkarni Division of Urology, Princess Margaret Hospital, University Health Network, Toronto, Ontario; Institute for Health Policy, Management, and Evaluation, University of Toronto
  • Robert K. Nam Division of Urology, Sunnybrook Health Sciences Center, University of Toronto, Toronto, Ontario; Institute for Health Policy, Management, and Evaluation, University of Toronto
Keywords: prostatic neoplasms, neoplasm metastasis, drug therapy, docetaxel, abiraterone acetate, decision support techniques

Abstract

Introduction: Our aim was to determine whether androgen deprivation therapy (ADT) with abiraterone acetate (AA) or ADT with docetaxel chemotherapy (DC) resulted in improved quality-adjusted life years (QALYs) among men with de novo metastatic castration-sensitive prostate cancer (mCSPC) and the cost effectiveness of the preferred strategy using decision analytic techniques.

Methods: A microsimulation model with a lifetime time horizon was constructed. Our primary outcome was QALYs. Secondary outcomes included cost, incremental cost effectiveness ratio (ICER), unadjusted overall survival (OS), rates of second- and third-line therapy, and adverse events. A systematic literature review was used to generate probabilities and utilities to populate the model. The base case was a 65-year-old patient with de novo mCSPC.

Results: A total of 100 000 microsimulations were generated. Initial AA resulted in a gain of 0.45 QALYs compared to DC (3.36 vs. 2.91 QALYs) with an ICER of $276 251.82 per QALY gained with initial AA therapy. Median crude OS was 51 months with AA and 48 months with DC. Overall, 46.6% and 42.6% of patients received second-line therapy and 8.7% and 7.9% patients received third-line therapy in the AA and DC groups, respectively. Grade 3/4 adverse events were experienced in 17.6% of patients receiving initial AA and 22.3% of patients receiving initial DC.

Conclusions: Although ADT with AA results in a gain in QALYs and crude OS compared to DC, AA therapy is not a cost-effective treatment strategy to apply uniformly to all patients. The availability of AA as a generic medication may help to close this gap. The ultimate choice should be based on patient and tumor factors.

Published
2020-03-29
How to Cite
Hird, A. E., Magee, D. E., Cheung, D. C., Matta, R., Kulkarni, G. S., & Nam, R. K. (2020). Abiraterone vs. docetaxel for metastatic hormone-sensitive prostate cancer: A microsimulation model. Canadian Urological Association Journal, 14(9), E418-27. https://doi.org/10.5489/cuaj.6234
Section
Original Research