SAFETY OF BRAND-NAME INFLIXIMAB VERSUS BIOSIMILARS IN INFLAMMATORY BOWEL DISEASE: REAL-WORLD EVIDENCE FROM U.S. CLAIMS DATA
Author(s)
Ning Lyu, MS, PhD1, Michaela Tracy, MD,MPH2, Benjamin N. Rome, MD3, Timothy Savage, MD3;
1Brigham and Women's Hospital and Harvard Medical School, Division of pharmacoepidemiology and Pharmacoeconomics and Harvard-MIT center for regulatory science, Boston, MA, USA, 2Boston Children's Hospital and Harvard Medical School, Boston, MA, USA, 3Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
1Brigham and Women's Hospital and Harvard Medical School, Division of pharmacoepidemiology and Pharmacoeconomics and Harvard-MIT center for regulatory science, Boston, MA, USA, 2Boston Children's Hospital and Harvard Medical School, Boston, MA, USA, 3Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
OBJECTIVES: Infliximab is widely used for the treatment of inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis. Biosimilar infliximab products were approved as lower-cost alternatives to the originator; however, real-world safety evidence in biosimilar users remains limited. This study compared the risk of infections between brand-name infliximab and biosimilars in patients with IBD.
METHODS: We conducted a cohort study using two US nationwide healthcare databases (2018 - 2025). Patients < 65 years with IBD who were biologic naïve and newly initiated on brand-name infliximab or a biosimilar were included. Serious infections were defined as infections requiring hospitalization. Outpatient infections were defined as a diagnosis with a targeted antimicrobial dispensed within one day. Within each database, 1:1 propensity score matching was applied to balance baseline demographic and clinical characteristics. Database-specific estimates were pooled using fixed-effects meta-analysis. Incidence rates and adjusted hazard ratios (aHRs) were estimated over 180 days of follow-up. Subgroup analyses were conducted by age group and IBD subtype.
RESULTS: In total, 3,791 patients initiated infliximab biosimilars and 6,881 initiated brand-name infliximab. After matching, 3,198 patients were included in each exposure group. The incidence rate of serious infections was 65 per 1,000 person-years among biosimilar users and 61 per 1,000 person-years among originator users, with no significant difference between groups (aHR 1.03; 95% CI, 0.78-1.44). For outpatient infections, incidence rates were 283 and 312 per 1,000 person-years, respectively, with no significant difference observed (aHR 0.92; 95% CI, 0.79-1.08). Findings were consistent across age groups, IBD subtypes.
CONCLUSIONS: In this real-world study of patients with IBD, infliximab biosimilars and the brand-name showed similar risks of serious and outpatient infections. These findings support the clinical comparability of biosimilars and may inform payer coverage, formulary decisions, and policies aimed at improving access to biologic therapies while controlling costs.
METHODS: We conducted a cohort study using two US nationwide healthcare databases (2018 - 2025). Patients < 65 years with IBD who were biologic naïve and newly initiated on brand-name infliximab or a biosimilar were included. Serious infections were defined as infections requiring hospitalization. Outpatient infections were defined as a diagnosis with a targeted antimicrobial dispensed within one day. Within each database, 1:1 propensity score matching was applied to balance baseline demographic and clinical characteristics. Database-specific estimates were pooled using fixed-effects meta-analysis. Incidence rates and adjusted hazard ratios (aHRs) were estimated over 180 days of follow-up. Subgroup analyses were conducted by age group and IBD subtype.
RESULTS: In total, 3,791 patients initiated infliximab biosimilars and 6,881 initiated brand-name infliximab. After matching, 3,198 patients were included in each exposure group. The incidence rate of serious infections was 65 per 1,000 person-years among biosimilar users and 61 per 1,000 person-years among originator users, with no significant difference between groups (aHR 1.03; 95% CI, 0.78-1.44). For outpatient infections, incidence rates were 283 and 312 per 1,000 person-years, respectively, with no significant difference observed (aHR 0.92; 95% CI, 0.79-1.08). Findings were consistent across age groups, IBD subtypes.
CONCLUSIONS: In this real-world study of patients with IBD, infliximab biosimilars and the brand-name showed similar risks of serious and outpatient infections. These findings support the clinical comparability of biosimilars and may inform payer coverage, formulary decisions, and policies aimed at improving access to biologic therapies while controlling costs.
Conference/Value in Health Info
2026-05, ISPOR 2026, Philadelphia, PA, USA
Value in Health, Volume 29, Issue S6
Code
CO42
Topic
Clinical Outcomes
Topic Subcategory
Comparative Effectiveness or Efficacy
Disease
SDC: Gastrointestinal Disorders, SDC: Infectious Disease (non-vaccine), STA: Biologics & Biosimilars