Real-world economic burden of metastatic castration-resistant prostate cancer before and after first-line therapy initiation.

Aims: To describe healthcare costs of patients with metastatic castration-resistant prostate cancer (mCRPC) initiating first-line (1 L) therapies from a US payer perspective.

Methods: Patients initiating a Flatiron oncologist-defined 1 L mCRPC therapy (index date) on or after mCRPC diagnosis were identified from linked electronic medical records/claims data from the Flatiron Metastatic Prostate Cancer (PC) Core Registry and Komodo's Healthcare Map. Patients were excluded if they initiated a clinical trial drug in 1 L, had <12 months of insurance eligibility prior to index, or no claims in Komodo's Healthcare Map for the Flatiron oncologist-defined index therapy. All-cause and PC-related total costs per-patient-per-month (PPPM), including costs for services and procedures from medical claims (i.e. medical costs) and costs from pharmacy claims (i.e. pharmacy costs), were described in the 12-month baseline period before 1 L therapy initiation (including the baseline pre- and post- mCRPC progression periods) and during 1 L therapy (follow-up).

Results: Among 459 patients with mCRPC (mean age 70 years, 57% White, 16% Black, 45% commercially-insured, 43% Medicare Advantage-insured, and 12% Medicaid-insured), average baseline all-cause total costs (PPPM) were $4,576 ($4,166 pre-mCRPC progression, $8,278 post-mCRPC progression). Average baseline PC-related total costs were $2,935 ($2,537 pre-mCRPC progression, $6,661 post-mCRPC progression). During an average 1 L duration of 8.5 months, mean total costs were $13,746 (all-cause) and $12,061 (PC-related) PPPM. The cost increase following 1 L therapy initiation was driven by higher PC-related outpatient and pharmacy costs. PC-related medical costs PPPM increased from $1,504 during baseline to $5,585 following 1 L mCRPC therapy initiation.

Limitations: All analyses were descriptive; statistical testing was not performed.

Conclusion: Incremental costs of progression to mCRPC are significant, with the majority of costs driven by higher PC-related costs. Using contemporary data, this study highlights the importance of utilizing effective therapies that slow progression and reduce healthcare resource demands despite the initial investment in treatment costs.