Real-World Outcomes Among US Veterans Health Administration Patients Newly Diagnosed with Metastatic Renal Cell Carcinoma and Treated with First-Line Monotherapy.

INTRODUCTION: Substantial unmet needs exist among patients with metastatic renal cell carcinoma (mRCC). This retrospective study evaluated treatment patterns as well as clinical and economic outcomes associated with first-line monotherapy among patients with mRCC in the USA. METHODS: Newly diagnosed patients with mRCC initiating at least one first-line therapy (1L) from 1 October 2013 to 31 March 2018 (index date = 1L start date) were identified from the US Veterans Health Administration database. Treatment patterns, clinical outcomes (time to next treatment [TNT] defined by earliest of switch to non-index therapy or re-initiation of index therapy after a more than 90-day gap, time to treatment discontinuation [TTD], overall survival [OS]), and costs were evaluated among patients treated with tyrosine kinase inhibitors (TKI), mammalian target of rapamycin inhibitors (mTOR), immune checkpoint inhibitors (ICI), and other monotherapies. Standard descriptive statistics were presented. The Kaplan-Meier method was used to evaluate clinical outcomes. RESULTS: Of 759 patients (median age 68.0 years), 85.0%, 8.0%, 4.3%, and 2.6% were treated with TKI, mTOR, ICI, or other therapy in 1L, respectively. Advancement rates (to second-line [2L] therapy) ranged from 10.0 (ICI) to 45.1 per 100 person years (TKI). The 12-month OS rates ranged from 47.4% (TKI) to 67.7% (mTOR). The median TNT ranged from 3.8 (mTOR) to 9.6 months (ICI), and median TTD ranged from 2.3 (mTOR) to 4.7 months (TKI). Total all-cause mean costs per patient per month ranged from $12,466 (mTOR) to $19,812 (ICI). CONCLUSION: These results indicate high unmet medical needs among patients with mRCC treated with 1L monotherapies. Novel combination therapies (e.g., ICI + ICI, ICI + TKI) may improve front-line outcomes for patients with poor prognoses.