Utilization patterns and characteristics of users of biologic anti‐inflammatory agents in a large, US commercially insured population

Abstract We report utilization patterns and characteristics of patients treated with biologic anti‐inflammatory agents in a large commercially insured patient population in the United States. We identified adult (age ≥18 years) patients receiving biologic anti‐inflammatory agents between 1 January 2012 and 31 March 2019 across the five Research Partners in the Biologic and Biosimilars Collective Intelligence Consortium's Distributed Research Network. We examined the number of incident use episodes for each biologic, as well as patient demographic and clinical characteristics. Curated data and analytic tools from the Food and Drug Administration's Sentinel System were used to perform the analyses. We identified 90,360 incident episodes of tumor necrosis factor‐alpha inhibitors (TNFi) and 70,506 incident episodes of non‐TNFi medications. Adalimumab was the most common TNFi drug (47% of all TNFi episodes) and showed a steady increase in utilization during the study period compared to other TNFi agents. Rituximab was the most commonly initiated non‐TNFi medication (44% of non‐TNFi episodes). Other non‐TNFi agents, namely, ustekinumab, vedolizumab, and secukinumab, demonstrated notable increases in utilization over time. Biosimilar use was limited; we observed 653 incident episodes for infliximab‐dyyb and 39 incident episodes for infliximab‐abda. As more biologics enter the market, greater variation in the use of biologics with similar indications and between biologic originators and biosimilars is anticipated. Because information on efficacy and safety at the time of drug approval is limited, post‐marketing surveillance and research is needed to monitor medication safety and evaluate effectiveness between biologic drugs using real‐world data.

each biologic, as well as patient demographic and clinical characteristics. Curated data and analytic tools from the Food and Drug Administration's Sentinel System were used to perform the analyses. We identified 90,360 incident episodes of tumor necrosis factor-alpha inhibitors (TNFi) and 70,506 incident episodes of non-TNFi medications. Adalimumab was the most common TNFi drug (47% of all TNFi episodes) and showed a steady increase in utilization during the study period compared to other TNFi agents. Rituximab was the most commonly initiated non-TNFi medication (44% of non-TNFi episodes). Other non-TNFi agents, namely, ustekinumab, vedolizumab, and secukinumab, demonstrated notable increases in utilization over time. Biosimilar use was limited; we observed 653 incident episodes for infliximab-dyyb and 39 incident episodes for infliximab-abda. As more biologics enter the market, greater variation in the use of biologics with similar indications and between biologic originators and biosimilars is anticipated. Because information on efficacy and safety at the time of drug approval is limited, post-marketing surveillance and research is needed to monitor medication safety and evaluate effectiveness between biologic drugs using real-world data.

| INTRODUC TI ON
Since the first biologic agent, recombinant human insulin, was approved in 1982, biologics have accounted for one of the fastest growing segments of the prescription drug market in the United States (US). 1,2 Biologic anti-inflammatory agents are used for the treatment of various, and oftentimes multiple, inflammatory diseases, including, but not limited to, rheumatoid arthritis (RA), psoriasis, Crohn's disease, ulcerative colitis, and multiple sclerosis. 3 Compared to chemically synthesized small-molecule drugs, large molecule biological medications are structurally more complex, and have the potential to be more targeted therapies. They also have limitations such as efficacy and safety concerns related to immunogenicity, and inherent natural variability. 4,5 Furthermore, the introduction of biosimilars has introduced even more complexity and opportunity into the real-world assessment of biologics for the treatment of anti-inflammatory disease.
This Short Report presents usage patterns and characteristics of patients treated with biologic anti-inflammatory agents in a large distributed network of commercially insured patients in the United States.
Whereas previous utilization studies have generally focused on single or selected biologic agents (e.g., tumor necrosis factor (TNF)-alpha inhibitors (TNFi) only) and have typically not considered indications across all therapeutic areas, our descriptive report provides a broad perspective of all relevant agents, indications, and all therapeutic areas.

| MATERIAL S AND ME THODS
We used data from the distributed research network (DRN) of the Biologics and Biosimilars Collective Intelligence Consortium (BBCIC), a non-profit research consortium dedicated to investigation of the real-   Tildrakizumab-asmn was not included in the analyses as there were <10 episodes for this product. Data are based on incident episodes, not unique users, except for the data stratified by sex that are based on unique users. The number of incident episodes may not be the same as the number of unique users. Individuals were counted multiple times if inclusion/exclusion criteria for incident episodes were met.
Sum of the numbers within a category may not be 100.0% because of rounding.

| RE SULTS
Over 30 million eligible health plan members who contributed more than 75 million person-years met the study eligibility criteria. We identified 160,866 incident episodes across all study medications, including 90,360 incident episodes of TNFi products and 70,506 incident episodes for non-TNFi medications (Table 1). We did not include tildrakizumab-asmn as there were As shown in Table 1   warranted. Also, further research on potential factors associated with utilization patterns will be informative, including cost of treatments, route of administration, prevalence of indications, adverse drug events, step therapy, patient and provider preferences, and pharmacy benefit programs. Ongoing monitoring of biologics utilization patterns will help strategically identify future research priorities.