Real-World Study Shows Equivalent Survival Outcomes for Abiraterone and Enzalutamide in Veterans with Metastatic Prostate Cancer

A comprehensive real-world study of veterans with metastatic hormone-sensitive prostate cancer (搜索)搜索该疾病 (mHSPC) has revealed identical survival outcomes between abiraterone查看药品详情 and enzalutamide查看药品详情, providing crucial comparative effectiveness data that has been lacking in clinical practice. The research, conducted within the Veterans Affairs (搜索)搜索该词条 healthcare system, represents the first direct comparison of these two widely used androgen receptor (搜索)搜索该靶点 inhibitors in a real-world clinical setting.

Equivalent Survival Across Patient Populations

The study analyzed all patients with mHSPC who initiated either abiraterone查看药品详情 or enzalutamide查看药品详情 between July 2017 and April 2023. Using inverse probability weighting analysis with abiraterone as reference, researchers found weighted median overall survival was comparable across the entire cohort at 36.2 months (P = .32). This equivalence held true across key subgroups, including Black veterans (39.7 months, P = .90) and those with cardiovascular disease (搜索)搜索该疾病 (31.5 months, P = .30).

"This is the first direct comparison of abiraterone查看药品详情 and enzalutamide查看药品详情 for mHSPC in a clinical practice setting," lead researcher Schoen told Federal Practitioner. "At the population level, there are no differences based on initial treatment choice."

Study Demographics and Clinical Characteristics

The patient populations were well-matched across treatment groups. Median ages were 73 years for abiraterone查看药品详情 patients and 74 years for enzalutamide查看药品详情 patients (P = .29). Racial distribution was similar between groups: abiraterone (68.1% White, 25.0% Black, 6.9% other/unknown) and enzalutamide (66.6% White, 27.0% Black, 6.4% other/unknown; P = .74).

The groups also showed similar rates of common comorbidities, including diabetes (搜索)搜索该疾病 (40.5% vs 46.3%, respectively, P = .07), peripheral vascular disease (搜索)搜索该疾病 (40.2% vs 37.6%, respectively, P = .44), and chronic pulmonary disease (搜索)搜索该疾病 (37.0% vs 40.5%, P = .29).

Cost Considerations Drive Treatment Selection

Within the VA system, abiraterone查看药品详情 has emerged as the preferred treatment option primarily due to economic factors. "In the VA, the preference for most patients is abiraterone since it is the least expensive agent," Schoen explained. The availability of a generic version for several years has further enhanced its cost-effectiveness profile.

The preference for abiraterone查看药品详情 is also influenced by clinical familiarity. "Abiraterone has been on the market for the longest, and therefore clinicians are familiar with its use," Schoen noted. However, he acknowledged that "clinicians have little idea of the comparative efficacy between these 2 agents."

Data from a 2025 study by Schoen and colleagues revealed significant growth in androgen receptor (搜索)搜索该靶点 inhibitor use, with 53.7% of veterans with mHSPC receiving such therapy in 2022, up from 16.9% in 2017.

Treatment Selection Considerations

Given the equivalent efficacy demonstrated in the study, researchers suggest that treatment decisions should be guided by cost and toxicity profiles rather than survival expectations. "The authors suggest that the cost and toxicities of the medications should guide clinician decisions," Schoen said.

Specific safety considerations include abiraterone查看药品详情's potential to worsen diabetes (搜索)搜索该疾病, as it is administered with prednisone查看药品详情 and could increase cardiovascular event risk. Conversely, enzalutamide查看药品详情 presents more drug-drug interaction concerns, particularly with anticoagulants commonly used in cancer patients.

Expert Commentary on Real-World Evidence Value

Hematologist-oncologist Natalie Reizine, MD, of the University of Illinois College of Medicine查看公司主页, Chicago, who was not involved in the study, emphasized the value of real-world data given clinical trial limitations. "It's difficult to compare clinical trials because they enroll different groups of patients," she explained. Clinical trials often exclude patients with significant comorbidities such as cardiovascular disease (搜索)搜索该疾病 or poorly controlled diabetes (搜索)搜索该疾病, yet "in real life, many of our patients have other medical problems that we have to manage."

Reizine particularly highlighted the study's diverse patient population as a significant strength. "Black men are very underrepresented in clinical trials. Many clinical trials that lead to drug approval will have only few or no Black men at all, yet these drugs go on to be widely prescribed to all men with prostate cancer (搜索)搜索该疾病."

Clinical Implications and Treatment Guidance

The study findings were described as "reassuring" by Reizine, especially considering previous studies suggesting abiraterone查看药品详情 and prednisone查看药品详情 may be associated with worse cardiovascular outcomes. "This study showed that in this VA population, even for patients who had cardiovascular disease (搜索)搜索该疾病, there was not a difference in how they did."

For treatment selection, Reizine recommended considering comorbidities and potential drug interactions. "One of the big reasons that you may not be able to safely prescribe enzalutamide查看药品详情, for instance, is if a patient is on an anticoagulant, which is incredibly common in cancer patients. Enzalutamide has more drug-drug interactions than abiraterone查看药品详情 and prednisone查看药品详情."

Additional Treatment Options

Beyond abiraterone查看药品详情 and enzalutamide查看药品详情, Schoen noted that newer agents apalutamide查看药品详情 and darolutamide查看药品详情 represent "viable options." Chemotherapies and certain targeted drugs are also available but "are only used in a select group of patients."

The study was supported by the American Society of Clinical Oncology查看公司主页 Conquer Cancer Foundation, the Prostate Cancer Foundation (搜索)搜索该公司, and the Blavatnik Family Foundation. The authors acknowledged limitations including the observational cohort design and data constraints.