4CPS-087 Adalimumab persistence in clinical practice at a regional hospital

• Published in: European journal of hospital pharmacy. Science and practice 2024-03, Vol.31 (Suppl 1), p.A93-A94
• Main Authors: Martínez González, J, Castro Salinas, P, Charques Trallero, V, Retamero Delgado, A, Mendiola García, S, Serrais Benavente, J, Ferràndez Martí, D
• Format: Article
• Language: English
• Subjects: Arthritis; Biological products; Conflicts of interest; Monoclonal antibodies; Section 4: Clinical pharmacy services
• ISSN: 2047-9956; 2047-9964
• DOI: 10.1136/ejhpharm-2024-eahp.191

Background and ImportanceCurrently, biosimilar drugs are a great cost-effective alternative to maintain the public health system sustainable.Aim and ObjectivesTo analyse persistence between biosimilar and originator adalimumab, as well as predictors associated with a higher risk of discontinuation.Material and MethodsRetrospective study conducted in a regional hospital with a reference area of 133,734 inhabitants.All patients who have been treated in our hospital with originator or biosimilar adalimumab were included. Patients switching were excluded.Variables studiedsex, age, treatment, indication, starting and ending date, previous treatments and reason for interruption.Kaplan-Meier method was used to analyse the 48 month retention rate and compared by a stratified log rank test. A Cox proportional hazards regression analysis stratified by age, sex, indication, year of prescription and reason for interruption was done.Statistical analysis was performed using SPSS Statistics v22. Categorical variables are shown with percentages and quantitative variables with median and interquartile range.ResultsThe study included 401 patients, 222 women (55.4%), median age 54.0 (43.0–63.0) years. Adalimumab biosimilar was indicated in 185 (46.1%) patients. Treatment duration for the originator vs biosimilar was 21.9 (5.7–61.8) vs 9.3 (5.0–20.7) months.Indication distribution137 (34.2%) rheumatoid arthritis, 74 (18.5%) psoriasis, 63 (15.7%) Chron disease, 50 (12.5%) psoriatic arthritis, 50 (12.5%) spondyloarthitis, 21 (5.2%) hidradenitis suppurativa, 3 (0.7%) ulcerative colitis, 2 juvenile idiopathic arthritis (0.5%), 1 SAPHO (0.2%).Main reasons for stopping adalimumab74 (18.5%) no response, 58 (14.5%) adverse effect, 47 (11.7%) loss of effectiveness and 33 (8.2%) remission.The overall 48-month retention rate was 17.2%. Estimated proportions of patients maintaining originator and biosimilar were 30.1% vs 2.2% after 48 months. Originator showed a higher survival retention (HR 0.42, 95% CI 0.34–0.53, p