BACKGROUND

Rheumatoid arthritis is a progressive disease that requires continuous treatment. Despite the excellent results, treatment with biologics and target-specific disease-modifying anti-rheumatic drugs often has to be interrupted due to insufficient therapeutic effectiveness, toxicity, or side effects.

PURPOSE

The purpose of this study is to identify the reasons and factors influencing treatment discontinuation with biologic and target-specific drugs among the Bulgarian patients with rheumatoid arthritis.

PATIENTS AND METHODS

This is a single-centre, retrospective observational cohort study, that includes 154 patients with seropositive rheumatoid arthritis, who underwent a total of 221 therapeutic courses with biologic and target-specific drugs over a period of 12 years.

RESULTS

Out of the 221 therapeutic courses, 103 (46.6%) were discontinued. Due to an initial lack of efficacy, treatment was interrupted in 38 of cases (36.9%). A secondary lack of efficacy led to the discontinuation of 24 treatment regimens (23.3%). Allergic reactions and "other" reasons necessitated the cessation of therapy in 41 cases (39.8%). The male gender (HR = 2.111; 95%CI 1.261-3.535), age below 59 years (HR = 1.791, 95%CI 1.162-2.760), shorter disease duration (HR = 0.995, 95%CI 0.993-0.998), co-morbidity with diabetes mellitus (HR = 3.463, 95%CI 1.189-10.090), cerebrovascular disease (HR = 2.490, 95%CI 1.215-5.102), and the type of medication were identified as factors influencing the interruption of treatment. Age (p = 0.012), disease duration (р=0.06), and therapy duration (р<0.01) have a significant impact on the reasons for treatment discontinuation.

CONCLUSIONS

Awareness of the reasons and factors influencing the discontinuation of treatment with biologic and target-specific drugs is crucial for improving existing therapeutic strategies and developing futures ones.