Switching and Discontinuation Patterns Among Patients Stable on Originator Infliximab Who Switched to an Infliximab Biosimilar or Remained on Originator Infliximab

Abstract

Objective

To compare switching and discontinuation patterns of patients stable on originator infliximab (IFX) who switched to an IFX biosimilar (switchers) or remained on originator IFX (continuers) in the United States.

Methods

Symphony Health Solutions’ Patient Transactional Datasets (10/2012–03/2019) were used to identify adults with ≥2 claims for either rheumatoid arthritis (RA), psoriatic arthritis, plaque psoriasis, ankylosing spondylitis, or inflammatory bowel disease (IBD); and ≥1 claim for originator or biosimilar IFX. The index date was the first IFX biosimilar claim for switchers or a random originator IFX claim for continuers. All patients were required to have ≥5 originator IFX claims during the 12 months pre-index (prevalent population). The subset of patients with ≥12 months of observation prior to the first originator IFX claim was also analyzed (incident population). Switchers were matched 1:3 to continuers. Discontinuation was defined as having ≥120 days between 2 consecutive index treatment claims.

Results

Prevalent switchers (N=1109) were 3.57-times more likely than continuers (N=3327) to switch to another originator biologic (hazard ratio [HR]=3.57, p<0.001). Of 249 prevalent switchers who switched to another originator biologic, 200 (80.3%) switched back to originator IFX. Incident switchers (N=571) were 2.55-times more likely than continuers (N=1713) to switch to another originator biologic (HR=2.55, p<0.001). Of 118 incident switchers who switched to another originator biologic, 90 (76.3%) switched back to originator IFX. Prevalent switchers were 1.25-times more likely than continuers to discontinue index therapy (HR=1.25, p<0.001). Similar results were observed in RA (prevalent population; switching: HR=3.49, p<0.001; discontinuation: HR=1.23, p=0.009) and IBD (prevalent population; switching: HR=3.82, p<0.001; discontinuation: HR=1.29, p=0.003) subgroups.

Conclusion

Patients switching from originator to biosimilar IFX were more likely to switch to another originator biologic (notably back to originator IFX) and discontinue index treatment than those remaining on originator IFX; however, reasons for switching are unknown.

Keywords:

• biosimilars
• chronic inflammatory disease
• treatment discontinuation
• infliximab
• treatment switching

Abbreviations

AS, ankylosing spondylitis; CD, Crohn’s disease; CI, confidence interval; CID, chronic inflammatory disease; DMARD, disease modifying anti-rheumatic drug; FDA, Food and Drug Administration; GPI, Generic Product Identifier; HCPCS, Healthcare Common Procedure Coding System; HIPAA, Health Insurance Portability and Accountability Act; HR, hazard ratio; ICD-9/10-CM, International Classification of Diseases, 9th/10th Revision, Clinical Modification; IBD, inflammatory bowel disease; IFX, infliximab; KM, Kaplan–Meier; NMS, non-medical switching; NSAID, non-steroidal anti-inflammatory drug; PDE4, phosphodiesterase-4; PsA, psoriatic arthritis; PSM, propensity score matching; PsO, plaque psoriasis; Quan-CCI, Quan-Charlson Comorbidity Index; RA, rheumatoid arthritis; SD, standard deviation; SHS, Symphony Health Solutions; UC, ulcerative colitis; US: United States.

Acknowledgments

Medical writing assistance was provided by Isabelle Ghelerter and Christine Tam, employees of Analysis Group, Inc.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

LM, MHL, BE, and PL are employees of Analysis Group, Inc., a consulting company that has provided paid consulting services to Janssen Scientific Affairs, LLC, which funded the development and conduct of this study and manuscript. IL, RM, KW, and TF are employees of Janssen Scientific Affairs, LLC and stockholders of Johnson & Johnson, the parent company of Janssen Pharmaceuticals, which manufactures and sells Remicade (infliximab). The authors report no other conflicts of interest for this work.

Additional information

Funding

This research was funded by Janssen Scientific Affairs, LLC. The sponsor was involved in the study design, interpretation of results, manuscript preparation, and publication decisions.