Real-World Characteristics and Treatment Patterns in Patients with Urticaria Initiating Omalizumab in the United States

BACKGROUND: Omalizumab is indicated for the management of chronic idiopathic urticaria (CIU) in patients aged 12 years or older with persistent hives that are not adequately controlled by H1 antihistamines. While its safety and efficacy in CIU patients have been evaluated in multiple clinical trials, real-world use of omalizaumab in CIU has not been well characterized. OBJECTIVE: To assess demographics, clinical characteristics, and treatment patterns of CIU patients who initiated omalizumab to better understand the usage of this agent in CIU management in the real world. METHODS: This retrospective cohort study used medical and pharmacy claims data in the United States from the HealthCore Integrated Database to identify patients with CIU newly treated with omalizumab (≥ 4 omalizumab claims within 6 months of the initial claim) between March 21, 2014, and October 31, 2015 (study intake period). The index date was defined as the date of the first claim for omalizumab during the study intake period. Demographic and clinical characteristics were described for patients treated with omalizumab, as were treatment patterns associated with omalizumab and concomitant medications associated with CIU treatment. Descriptive and inferential statistics were reported. The Kaplan-Meier method was used to examine omalizumab treatment patterns. RESULTS: This study included 298 omalizumab-treated patients (mean [SD] age of 43.5 [13.64] years; 70.8% female); approximately 84% were seen by an allergist/immunologist. All patients had ≥ 12 months of continuous enrolment and a subset of 138 patients had ≥ 18 months of follow-up. For patients with ≥ 12 months of post-index follow-up, 12.1% (n = 36), 28.5% (n = 85), and 32.9% (n = 98) discontinued omalizumab within the 6-month, 12-month, and the entire post-index periods (mean 530 days), respectively; the mean number of days patients were continuously treated with omalizumab was 443.1 (95% CI = 425.0-461.3); the probabilities of continuous treatment (95% CI) were 0.879 (0.836-0.911), 0.711 (0.656-0.759), and 0.647 (0.585-0.703) for the 6-, 12-, and 18-month post-index periods, respectively. For the 98 patients who discontinued omalizumab during the entire post-index period, 28.6% restarted omalizumab after the first discontinuation within the post-index period (mean time from first discontinuation to first restart=329 days). Use of medications such as oral corticosteroids, montelukast, cyclosporine, and prescription H1 and H2 antihistamines decreased during the 1- to 6-month and 7- to 12-month post-index periods compared with those within the 6-month pre-index period. CONCLUSIONS: In this cohort of CIU patients who were newly prescribed omalizumab, the majority were treated by allergists/immunologists as expected, and approximately 60% of patients continued on therapy beyond 18 months. Concomitant medication use decreased after omalizumab initiation. These data on the real-world use of omalizumab for CIU may help to better inform decision-making processes for health care payers by quantifying omalizumab and concomitant medication treatment patterns over a longer time frame relative to previous studies.