Cost-effectiveness of enzalutamide versus apalutamide versus androgen deprivation therapy alone for the treatment of metastatic castration-sensitive prostate cancer in Canada

Abstract

Aims

There are no direct comparisons of the relative cost-effectiveness of second-generation anti-androgens (enzalutamide and apalutamide) used in managing metastatic castration-sensitive prostate cancer (mCSPC) in Canada. This study compared the cost-effectiveness of enzalutamide versus apalutamide versus androgen deprivation therapy (ADT) alone (standard of care) in patients with mCSPC from the Canadian public payer perspective using a Markov model with a 15-year time horizon.

Materials and methods

Efficacy data for enzalutamide and ADT alone were informed by the ARCHES and ENZAMET clinical trials, while a Bayesian network meta-analysis enabled comparison with apalutamide and ADT alone.

Results

Over the 15-year period, enzalutamide achieved the highest number of life-years (LY, 7.6) and quality-adjusted life-years (QALY, 5.62) compared with apalutamide (LY, 6.1; QALY, 4.59) and ADTs (LY, 4.9; QALY, 3.61). Enzalutamide incurred the most costs ($349,345) compared with apalutamide ($294,349) and ADT ($162,550). Sequential analysis showed that enzalutamide lies on the cost-effectiveness frontier with ADT alone (incremental cost-effectiveness ratio: $92,868/QALY), with apalutamide extendedly dominated through enzalutamide and ADT alone.

Limitations

Limitations include the heterogeneity of the studies included in the network meta-analysis and the validations for the treatment sequencing assumptions in the modeling.

Conclusions

Enzalutamide was the most effective treatment option for mCSPC in the Canadian market, with the greatest LYs and QALYs, and incurred the most costs.

Keywords:

• Enzalutamide
• apalutamide
• metastatic castration-sensitive prostate cancer
• androgen deprivation therapy
• cost-effectiveness

JEL classification codes:

• C11
• C15
• I11

Transparency

Declaration of funding

The study was funded by Astellas Pharma Inc. and Pfizer Inc., the co-developers of enzalutamide. The sponsors had a role in the study design, data analysis and interpretation, and writing of the report. All authors had full access to all data and the corresponding author had final responsibility for the decision to submit for publication. The manuscript was written with editorial support from medical writers, funded by the sponsors. The authors developed the analysis plan and all stages of the manuscript in collaboration with Astellas Pharma Inc. and Pfizer Inc.

Declaration of financial/other relationships

FS has received grants from Astellas, AstraZeneca, Bayer, BMS, Janssen, Merck, Myovant, Pfizer, and Sanofi; consulting fees from Amgen, Astellas, AstraZeneca, Bayer, BMS, Janssen, Merck, Myovant, Pfizer, and Sanofi; and honoraria from Amgen, Astellas, AstraZeneca, Bayer, BMS, Janssen, Merck, Myovant, Pfizer, and Sanofi. AC is an employee of Astellas Pharma Inc. BH is an employee of Astellas Pharma Inc. SM is an employee of IQVIA, which received funding from Astellas to conduct the statistical analyses for this work under consultancy contract. AG is an employee of Astellas Pharma Inc. SN has received grant support from Astellas and honoraria from Astellas and Janssen. BS has no competing interests to declare.

Peer reviewers on this manuscript have received an honorarium from JME for their review work but have no other relevant financial relationships to disclose.

Author contributions

FS: Conceptualization, Data curation, Formal analysis, Investigation, Supervision, Writing – original draft. AC: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Validation, Visualization, Writing – review & editing. BH: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Validation, Visualization, Writing – review & editing. SM: Conceptualization, Formal analysis, Methodology, Visualization, Writing – review & editing. AG: Conceptualization, Methodology, Data interpretation, Writing – review & editing. SN: Methodology, Visualization, Writing – review & editing. BS: Conceptualization, Methodology, Supervision, Writing – review & editing.

Acknowledgements

The development of the economic model was supported by Gittan Blezer from IQVIA Inc. Medical writing support was provided by Aitor Alvarez-Fernandez, PhD, and Paul Littlebury, PhD, from Bioscript and editorial assistance was provided by Stephanie Rippon, MBio, and Jane Beck, MA, from Complete HealthVizion, all funded by the study sponsors.

Data availability statement

Researchers may request access to anonymized participant-level data, trial-level data, and protocols from Astellas sponsored clinical trials at www.clinicalstudydatarequest.com. For the Astellas criteria on data sharing, see: https://clinicalstudydatarequest.com/Study-Sponsors/Study-Sponsors-Astellas.aspx.