BACKGROUND: Immune-mediated inflammatory diseases (IMIDs) share similar disease development pathways and pharmacological treatment modalities. First line therapy recommendations for patients newly diagnosed with IMIDs are non-biologic (traditional) medica-tions, such as methotrexate or corticosteroids. Non-adherence to treat-ment has been associated with recurrence and progression of disease. Adding or switching to a biologic specialty medication is indicated for patients with increased severity. Understanding early first line treatment patterns and the progression to specialty medication use could inform patient management strategies.
OBJECTIVE: To identify and describe a cohort of new users with IMID initiating first line treatment, and to describe one year post-initiation treatment patterns, including adherence to first line therapy.
METHODS: We conducted a retrospective observational cohort study using administrative claims data. The study cohorts consisted of patients aged 18-89 years indexed on the first line prescription claim (1/01/2014-12/31/2015), 12 months pre- and post-index continuous enrollment, evidence of select joint, skin, gastrointestinal (GI) conditions within 90 days of index, and naïve to first line and specialty medications in the pre-index period. Post-index treatment patterns were described.
RESULTS: New user cohorts for selected joint (n = 3,163), skin (n = 3,732), and GI (n = 1,530) conditions were identified. For all conditions, patients were majority female with an average age greater than 65 years. Co-occurrence of conditions was most common for selected joint conditions (8.0%), and least common for selected GI (3.8%) conditions. The majority (95.8%) of first line new users started on mono-therapy. Adherence to first line therapy based on proportion of days covered (> 0.8) in the post-index period was low for joint (19.9%), skin (43.7%), and GI (5.3%) conditions. Few patients switched or added a specialty therapy within one year within the cohorts (joint [< 1%], skin [< 1%], and GI [1.5%] conditions).
CONCLUSIONS: Adherence to first line therapy and escalation to specialty treatment were found to be low among cohorts of new users of non-specialty medications with IMIDs within a year of initiating a non-specialty first line therapy. Given the risk of increased disease severity and escalation to specialty treatment for patients with IMIDS beyond one year, healthcare clinicians should focus on scalable interventions that help patients with early adherence to first line therapy. Time to escalation to specialty medication beyond one year may war-rant additional study.
