Background The treatment of Rheumatoid Diseases (including RA, AS, PsA) has evolved in recent years with continued development and introduction of subcutaneous (SC) TNF-alpha blockers.
Objectives The objective of this study is to compare treatment persistence among the available SC TNF-alpha blocker: adalimumab (ADA), certolizumab (CDP), etanercept (ETA), or golimumab (GLM) by RD patients.
Methods A retrospective cohort study was conducted using data from the National Swedish Prescription and Patient Registries. Adult (≥18 years old) RD patients, with at least one prescription of ADA, CDP, ETA, or GLM from rheumatoid related departments (Rheumatoid, Rehabilitation, Orthopedics, or other department where the prescriber was a rheumatologist) between May 2010 and December 2012 were extracted, with the first prescription date serving as the index date. Patients were required to have lived in Sweden for 12 months prior the index date (baseline period). Propensity score matching was used to enhance comparability in the observed baseline characteristics of the patients in paired groups treated with individual index subcutaneous biologic. The matching variables were: age, sex, index year, Charlson Comorbidity Index Scores (0, 1, 2+), methotrexate treatment during baseline period, and hospitalization during baseline period. Persistence with index subcutaneous biologic was defined as time (in consecutive days) from treatment initiation until treatment discontinuation (continuous ≥60-day lapse in medication coverage). A Kaplan-Meier time-to-event (“survival”) analysis was performed to estimate the proportion of patients who remained persistent to index subcutaneous biologic following the index date and up to three years thereafter. Patients were right censored for the first of death, emigration, three years of follow-up, or data limit of the Prescription Register (July 2014), Comparisons of persistence between groups were conducted using the log rank test.
Results A total of 4,905 RD patients who met the criteria were identified. Among these patients, 1,824 (37%), 622 (13%), 1,705 (35%), and 754 (15%) were treated with ADA, CDP, ETA, and GLM, respectively. The mean (SD) age of the patients was 52 (15) years with 62% being female. The crude persistence estimates with the four treatments are presented in Figure 1. After propensity score matching, 738 GLM patients were compared to 738 ADA patients with the proportion of patients persistent at three years estimated at 39.5% vs 31.1% (p=0.025), respectively. The corresponding numbers for the GLM to ETA comparison were 754 patients in each group, with 39.5% vs 30.0% (p<0.01) being persistent after three years, respectively. The corresponding numbers for the GLM to CP comparison were 484 patients in each group, with 38.3% vs 31.2% (p=0.55) being persistent after three years, respectively
Conclusions The results show that biologic naïve RD patients 3 years after treatment initiation with GLM had significantly higher persistent rate than ETA and ADA in Sweden. Further research is needed to explore the association of treatment patterns with the real-life clinical, economic and humanistic outcomes.
Disclosure of Interest A. Svedborn: None declared, J. Dalen: None declared, R. Lyu Employee of: Merck, Q. Ding Employee of: Merck, S. Sajjan Employee of: Merck, V. Sazonov Employee of: Merck, C. Black Employee of: Merck, S. Kachroo Employee of: Merck