Sorafenib for Desmoid Tumors. A Cost Analysis: Too Much for Too Little?

Abstract Background: A recent randomized trial showed that sorafenib increased progression free survival (PFS) in patients with desmoid tumors despite many patients experiencing stable disease or spontaneous regression without treatment. Using these trial data, we completed a cost analysis of sorafenib efficacy through two years of treatment. Methods: 2019 Medicare Part D rates for sorafenib were used (dose 400 mg/day, cost $309/day). Yearly costs per progression and objective response were calculated. Radiologic progression and response were defined using Response Evaluation Criteria in Solid Tumors (RECIST). Patients with disease progression were separately analyzed in two groups: both clinical and radiologic (CAR), and radiologic alone. Results: 84 previously randomized patients were analyzed (placebo: 35, sorafenib: 49). After 1 year, sorafenib was associated with 43% absolute risk reduction (ARR) of CAR progression and number-needed-to-treat (NNT) of 2.3 patients/year, costing $259,406. After 2 years, ARR was 48% and NNT of 2.1 patients/year, costing $473,697. When assessing only patients with RECIST defined radiologic progression, sorafenib patients had ARR of 13.9% with NNT 7.2 and estimated costs of $812,052 at one year. Two-year ARR was 17.5% with NNT 5.7 and estimated costs $1,285,052. Sorafenib patients experienced improved RECIST partial response rates at 1 and 2 years of 14.7% and 14.3%, with NNT 6.8 and 6.9, and costs of $766,938 and $1,556,433; respectively. Conclusion: For the treatment of desmoid tumors, Sorafenib led to improved PFS, but at a substantial cost per patient. Beneficial RECIST outcomes were less likely and at higher cost. Patients should be informed of possible benefits of treatment versus potential financial burden.