The impact of biological and targeted synthetic disease-modifying antirheumatic drugs on patient costs: a cross-sectional study.

OBJECTIVES: Financial toxicity, defined as the detrimental impact of treatment-related costs on patients' lifestyles, has gained increasing recognition and is now managed similarly to treatment-related physical toxicities. We aimed to investigate the association between the use of biologic or targeted synthetic disease-modifying anti-rheumatic drugs (bDMARDs or tsDMARDs, respectively) and financial toxicity in patients with rheumatoid arthritis. METHODS: A cross-sectional study was conducted using data from the NinJa 2020 database. Exposure was defined as the use of bDMARDs or tsDMARDs. Financial toxicity was assessed using the 11-item COmprehensive Score for financial Toxicity (COST). Multivariable linear regression analysis was performed to evaluate the association between bDMARD or tsDMARD use and financial toxicity, with adjustments for age, sex, disease activity, type of employment, marital status and cancer diagnosis within 1 year. RESULTS: Among 1,732 patients (mean age: 66.3 years; women: 80.8%), 29.3% and 6.8% used bDMARDs and tsDMARDs, respectively. The mean COST score was 25.3 (standard deviation, 6.6). The use of bDMARDs or tsDMARDs was significantly associated with greater financial toxicity (-1.82 points) after adjusting for covariates. Furthermore, higher out-of-pocket expenses for DMARDs were associated with increased financial toxicity in patients with rheumatoid arthritis. Every JPY 10000 (USD 94.3) increase in co-payment corresponded to a 0.42-point decline in the COST score. CONCLUSIONS: The use of bDMARDs or tsDMARDs is associated with increased financial toxicity among patients with rheumatoid arthritis. Clinicians should proactively consider the financial implications of these therapies, engage in shared decision-making, and explore strategies to reduce costs or offer treatment alternatives while maintaining effective disease control.