Compared with patients without access restrictions to biologic or targeted synthetic disease-modifying antirheumatic drugs (DMARDs) or with psoriatic arthritis (PsA) only, patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) whose insurance plans restrict access to these DMARDs have lower odds of treatment effectiveness, according to study results published in PharmacoEconomics Open.
According to the researchers, novel DMARDs can slow disease progression in RA and PsA; however, many health insurance plans require prior authorization or step therapy for access to these treatments. The objective of this study was to compare treatment effectiveness in patients with RA or PsA with and without plan-level access restrictions to biologic or targeted synthetic DMARDs, and also to compare medication adherence between each group.
Researchers used the IBM MarketScan Commercial Claims and Encounters Database to analyze data from patients aged 18 to 64 years with RA or PsA with ≥1 claims for subcutaneous biologic DMARDs between January 2014 and December 2015. Patients included in the study were stratified into 1 of 2 cohorts: RA with or without PsA, and PsA only. The primary outcome was treatment effectiveness during the 12 months after the first DMARD claim; the secondary outcome was adherence to the index medication. Multivariate analysis was used to examine differences in the primary outcome of treatment effectiveness between patients with and without DMARD access restrictions.
Researchers revealed that among patients with RA (n=3993) and PsA (n=1713), 34.2% and 35.1%, respectively, had plan-level access restrictions. Among patients with access restrictions, 70.5% and 78.9% of patients with RA and PsA, respectively, had plans that required step therapy. The odds of treatment effectiveness during the 12-month follow-up were 19% lower among patients with RA (odds ratio [OR], 0.81; 95% CI, 0.67-0.98; P =.033) and 27% lower among patients with PsA whose plans included step therapy (OR, 0.73; 95% CI, 0.5-0.98; P =.037) compared with patients whose plans did not include step therapy. The odds of medication adherence among patients enrolled in plans with vs without step therapy were 19% lower among patients with RA (OR, 0.81; 95% CI, 0.68-0.96; P =.014) and 29% lower among patients with PsA (OR, 0.71; 95% CI, 0.54-0.94; P =.017).
Study limitations included possible miscoding or undercoding of the datasets used, lack of control for several baseline characteristics and medication use behaviors in patients, and the inability to generalize data for patients who were uninsured or had other types of insurance plans.
Researchers concluded, “Compared with patients in plans without access restrictions or with PsA only, patients [with] RA and PsA in insurance plans with step therapy had lower odds of treatment effectiveness, mainly [because of] lower odds of adhering to treatment, during the 12 months [after] subcutaneous [biologic] DMARD initiation.”
Disclosure: This clinical trial was supported by Elli Lilly and Company. Please see the original reference for a full list of authors’ disclosures.
Boytsov N, Zhang X, Evans KA, Johnson BH. Impact of plan-level access restrictions on effectiveness of biologics among patients with rheumatoid or psoriatic arthritis. Pharmacoecon Open. 2020;4(1):105-117.