Treatment patterns of rheumatoid arthritis in Japanese hospitals and predictors of the initiation of biologic agents

Abstract

Objective: To describe the usage of different biologic agents for rheumatoid arthritis (RA) in Japan over time and to identify factors that affects the decision to initiate treatment with biologic agents. Determinants of a switch to another biologic agent for patients who are already on biologic treatment were also analyzed.

Research design and methods: We utilized a hospital claims database containing 36,504 Japanese patients with a confirmed RA diagnosis. To analyze the determinants of treatment choices, we applied logistic regression analysis taking into account socio-demographic and medical factors.

Results: Analyses determined that 11.8% of diagnoses and 25.4% of treated patients in Japan receive a biologic agent. Significant factors associated with biologic treatment initiation include younger age, female sex, and a higher comorbidity index. The route of administration plays a major role when it comes to a switch between different biologic agents.

Conclusions: The lower likelihood of elderly patients to be initiated on biologic treatment might be explained by the risk aversion of Japanese physicians’ and patients who are afraid of the potential side effects of biologics. This finding is also consistent with the notion of an age bias that impedes elderly patients from optimal access to biologic treatment. Because claims data does not contain clinical parameters such as disease activity the results should be validated in a clinical context.

Keywords:

• Age bias
• Japan
• Rheumatoid arthritis
• Treatment initiation
• Treatment switch

Notes

Transparency

Declaration of funding

This study was funded by Janssen Pharmaceutical KK, who had no role in the study design, data collection, data analysis, data interpretation, or writing of the report. The corresponding author had the final responsibility for the decision to submit for publication. The findings and conclusions in this manuscript do not necessarily reflect the view of Janssen Pharmaceutical KK.

Declaration of financial/other relationships

J.M. and R.S. have disclosed that they are affiliated with Janssen Pharmaceutical KK, a company that markets drugs for the treatment of RA.

CMRO peer reviewer 1 has disclosed that she is an employee of Corrona LLC. Peer reviewer 2 has disclosed that he has received grants from BMS, Roche, Merck, AbbVie, Janssen, Pfizer and Eli Lilly; he is also a consultant to BMS, AbbVie and Janssen. Peer reviewers 3 and 4 have no relevant financial or other relationships to disclose.

Acknowledgments

The authors would like to thank the department of Health Economics, Janssen Pharmaceutical KK, for allowing us to conduct this study. We also want to thank to J. Ludovic Croxford for proof reading and editing the manuscript.

Notes

1. Actemra is a registered trade name of Genentech USA, Inc., South San Francisco, CA, USA

2. Orencia is a registered trade name of Bristol-Myers Squibb Company, New York, NY, USA

3. Enbrel is a registered trade name manufactured by Immunex Corporation, Thousand Oaks, CA 91320. Marketed by Amgen Inc, Thousand Oaks, CA, USA

4. Remicade is a registered trade name of Janssen Biotech, Inc, Horsham, PA, USA

5. Humira is a registered trade name of AbbVie Inc., North Chicago, IL, USA

6. Simponi is a registered trade name of Janssen Biotech, Inc, Horsham, PA, USA

7. Cimzia is a registered trade name of UCB Group of Companies, Smyrna, GA, USA

8. Xeljanz is a registered trade name of Pfizer Inc., New York, NY, USA