Background: There is a paucity of long-term real-world evidence comparing the effectiveness of ixekizumab (IXE) and adalimumab (ADA). We compared real-world treatment patterns of IXE-treated and ADA-treated patients with psoriasis over 24 months in the United States.
Methods: A retrospective observational study was conducted using IBM Watson Health MarketScan® databases. Adult patients with psoriasis having ≥1 claim for IXE or ADA from March 1, 2016 – October 31, 2019 were identified. Inverse probability of treatment weighting (IPTW) was used to address cohort imbalances. Cox proportional hazards models were used to estimate the risks of non-persistence, discontinuation, and switching. Logistic regression was used to estimate odds of high adherence. Persistence, adherence, discontinuation, reinitiation, and dosing and switching rates were also analyzed.
Results: The final cohorts comprised 475 IXE users and 3159 ADA users over 24 months. IXE users demonstrated higher adherence (36.3% vs 28.8%; P<0.001) and persistence rates (35.2% vs 28.8%; P=0.004), and a lower discontinuation rate (59.1% vs 65.3%; P=0.007) compared to ADA users. IXE users had a higher likelihood of being treatment-adherent compared to ADA users (OR=1.52, 95% CI: 1.24–1.87), a lower risk of non-persistence (HR=0.84, 95% CI: 0.75–0.95), and a lower risk of discontinuation (HR=0.83, 95% CI: 0.74–0.94), respectively. Switching rates were similar in both groups (31.2% vs 30.0%; P=0.608).
Conclusion: IXE users had better treatment adherence and persistence, and a lower risk of discontinuation compared to ADA users over 24 months. There was no difference in the risk of switching between IXE and ADA. J Drugs Dermatol. 2022;21(4):399-407. doi:10.36849/JDD.6336.