1209: Impact of Change in Disease Modifying Antirheumatic Drug Therapy on Disease Activity Measures: Findings from a Large Contemporaneous Real-World Longitudinal Database of Psoriatic Arthritis Patients

Zhaohui Su¹, Lauren Stevens², Tom Brecht¹, Jessica Paulus¹ and Stefan Weiss³, ¹OM1, Inc., Boston, MA, ²OM1, Inc., Lexington, KY, ³OM1, Inc., Chapel Hill, NC

Background/Purpose: While many clinical trials provide direct comparisons between biologic disease modifying antirheumatic drugs (bDMARD) and nonbiologic DMARDs (nDMARD), there is a need for to better understand the effectiveness of these therapies in routine clinical practice. We evaluated changes in disease activity measures associated with a change in DMARD therapy among a large cohort of patients with Psoriatic Arthritis (PsA) treated in routine clinical practice.

Methods: The OM1 platform collects, links, and leverages, structured and unstructured data from electronic medical records (EMR) and other sources in an ongoing and continuously updating manner. The OM1 PremiOM-PsA dataset includes data on approximately 55,000 patients. This analysis included patients who were treated with nDMARD at any time from January 2013 through May 2022 who had not previously received a bDMARD, and whom added or switched to either another nDMARD or to a bDMARD during the observation period (date of change in therapy is the index date). Established American College of Rheumatology endpoints for standard disease activity measures (RAPID-3, CDAI, DAS28) were used to define remission. Advanced natural language processing was used to estimate missing disease activity categories. Drug eras were defined using Observational Medical Outcomes Partnership (OMOP) definitions. Survival analyses were conducted to evaluate time to initial remission and confirmed remission, defined as 2 consecutive disease activity scores denoting remission, after index. To reduce the impact of subsequent treatment changes, follow-up was censored at 12 months. Patients who switched DMARDs or added another nDMARD after index, but subsequently switched to a bDMARD before achieving remission status were considered as treatment failures.

Results: This analysis included 1,257 patients who met study inclusion criteria, had disease activity measures at baseline, and were not in remission at index date. A total of 687 (54.6%) added or switched to another nDMARD and 570 (45.4%) added or switched to a bDMARD. There were an average of 4.0 disease activity measures per patient and a total of 5,002 disease activity measures during the 12 month follow-up period. A larger proportion of patients in the bDMARD group achieved initial remission (19.1% versus 12.5%, p< 0.05) and confirmed remission (6.5% versus 3.6%, p< 0.05) compared to the nDMARD group. Time to remission was similar between the bDMARD group and the nDMARD group (mean (SD) 4.8 (3.1) months bDMARD v. 4.8 (3.3) months nDMARD, p=0.63), among those who achieved remission status and excluding patients considered treatment failures.

Conclusion: Disease activity improved with changes in DMARD therapy. The addition of bDMARDs was associated with a higher proportion of patients reaching remission. This study expands on prior observational studies in a much larger and contemporaneous cohort of patients under conditions of routine clinical practice. Further research is needed to assess the impact of specific bDMARDs on time to remission.

Disclosures: Z. Su, OM1, Inc.; L. Stevens, OM1, Inc.; T. Brecht, OM1, Inc.; J. Paulus, None; S. Weiss, OM1.