Comparison of Real-World Treatment Patterns Among Biologic-Experienced Patients with Psoriasis Treated with Ixekizumab or Secukinumab Over 18 Months

INTRODUCTION: Real-world data comparing effectiveness of ixekizumab (IXE) and secukinumab (SEC) among biologic-experienced patients are limited. This study compared treatment patterns over 18 months among biologic-experienced patients with psoriasis receiving IXE or SEC in the USA. METHODS: A retrospective observational study using administrative claims data from IBM(®) Watson Health MarketScan(®) Research Databases included adult patients with ≥ 1 inpatient or ≥ 2 non-diagnostic (≥ 30 days apart) outpatient claim/s with diagnosis of psoriasis between March 1, 2015 and October 31, 2019, and ≥ 1 claim/s for index drugs, IXE or SEC, between March 1, 2016 and October 31, 2019. Patients had to have ≥ 1 claim/s for biologics indicated for psoriasis in the 6-month pre-period. During the 18-month follow-up, treatment adherence (proportion of days covered [PDC]), high adherence (PDC ≥ 80%), persistence, discontinuation, reinitiation, and switching were assessed. To address cohort imbalances, inverse probability of treatment weighting was employed. Logistic regression was used to estimate odds ratio for high adherence. Cox proportional hazard models were used to estimate hazard ratio for non-persistence, discontinuation, and switching. RESULTS: Overall, 411 IXE and 780 SEC users were included. After weighting, IXE users had significantly higher rate of high treatment adherence (42% vs. 35%, p = 0.019), higher persistence rate (44.9% vs. 36.9%, p = 0.007), lower discontinuation rate (48.4% vs. 56.0%, p = 0.012), and lower switching rate (26.6% vs. 34.0%, p = 0.009) compared with SEC users. After multivariable adjustment, compared with SEC, IXE use was associated with 36% higher odds of high treatment adherence (OR 1.36, 95% CI 1.05–1.74), 20% lower risk of treatment non-persistence (HR 0.80, 95% CI 0.68–0.93), 19% lower risk of discontinuation (HR 0.81, 95% CI 0.68–0.96), and 25% lower risk of switching (HR 0.75, 95% CI 0.60–0.93). CONCLUSION: This study suggests that IXE treatment is associated with significantly higher adherence rates and significantly lower non-persistence, discontinuation, and switching compared with SEC treatment.