Background/Purpose: To identify opportunities to optimize treatment of AS, an understanding of the treatment approaches and patient characteristics is necessary. This study describes comorbidities, comedications, and biologic treatment patterns, including any gender differences, in AS patients initiating biologics in the real-world setting.

Methods: This retrospective observational study analyzed US commercial claims data (IBM® MarketScan®) from 2012–2017. AS patients newly initiating a biologic (1st claim [index date] and no claims for ≥1 year prior), ≥18 years old, with continuous enrollment in the 12-months preceding (baseline) and following (follow-up) the index date were identified. Diagnoses were based on ICD 9/10 codes. Persistence was defined as treatment with the index biologic with gaps of ≤90 days over 12 months. The following treatment outcomes were also assessed: 110% of the label-recommended dose for ≥30 days (above-label dosing), new biologic initiation within 90 days of discontinuing index biologic (switch), and index biologic cessation ( >90 days with no treatment [non-switch discontinuation]). Patients were categorized based on the first event experienced.

Results: A total of 1,526 patients met the inclusion criteria. Women (n=668) were more likely than men (n=858) to have ≥1 claim at baseline for anxiety (17% vs 8%), depression (23% vs 10%), fatigue (29% vs 21%) and fibromyalgia (≥2 codes) (16% vs 6%). At baseline, women were more likely to have ≥1 claim for an opioid (59% vs 50%) or an NSAID (72% vs 67%) and to have claims for ≥2 different NSAIDs (33% vs 23%). The same trend was present in follow-up comparing women to men for opioids (69% vs 63%) and NSAIDs (75% vs 66%). The most common index biologics were adalimumab (52%) and etanercept (31%). Persistence of the index biologic at 12 months was 50% and was lower in women (43%) vs men (55%). The most frequent treatment outcome assessed was non-switch discontinuation (35%), followed by switching (16%) and above label dosing (16%). Among those who discontinued without switching, 14% restarted their index biologic within 6 months. Women were more likely to switch than men (20% vs 13%) and were less likely to be receiving a biologic (index or otherwise) at 12 months (71% vs 78%).

Conclusion: Index biologic treatment included primarily adalimumab and etanercept. The comorbidity and treatment exposures depict a more complex profile for women vs men, which may be important to consider when determining the best approach to disease management. Further real-world studies on treatment patterns are needed to understand factors leading to poor persistence and how best to optimize treatment.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/gender-differences-in-comorbidities-and-treatment-utilization-among-ankylosing-spondylitis-patients-initiating-a-biologic-in-a-real-world-setting/