Uptake of Biosimilars and Its Economic Implication for the Treatment of Patients with Rheumatoid Arthritis in Korea

Drug Persistence and Incidence of Active Tuberculosis of Tumor Necrosis Factor Alpha Inhibitors Versus Tocilizumab as the First-Line Biological Treatment in Patients with Rheumatoid Arthritis: A Nationwide Population-Based Retrospective Cohort Analysis

INTRODUCTION

Drug persistence may be a surrogate marker that reflects both long-term efficacy and safety in clinical settings, and tuberculosis (TB) is considered as one of the most important opportunistic infections after the biological treatment in rheumatoid arthritis (RA). We aimed to compare drug persistence and incidence of TB between tumor necrosis factor alpha (TNFα) inhibitors and tocilizumab in patients with RA using data from the Korean Health Insurance Review and Assessment Service database.

METHODS

In this analysis, 5449 patients with RA who started TNFα inhibitors, such as adalimumab, etanercept, infliximab, and golimumab or tocilizumab, as the first-line biological therapy between January 2014 and December 2017 were analyzed and followed up until December 2019. Drug persistence was defined as the duration from initiation to first discontinuation, and TB was defined as the prescription of > 2 anti-TB medications after the initiation of biologics.

RESULTS

TNFα inhibitors and tocilizumab were prescribed in 4202 (adalimumab, 1413; etanercept, 1100; infliximab, 769; golimumab 920) and 1247 patients with RA, respectively. During the analysis period, 2090 (49.7%) and 477 (38.3%) patients with RA discontinued TNFα inhibitors and tocilizumab, respectively, and 42 patients with RA developed TB (TNFα inhibitors, 33; tocilizumab, 9). After adjustment for confounding factors, TNFα inhibitors were significantly associated with a higher risk of discontinuation compared with tocilizumab (hazard ratio (HR) 1.63, p < 0.001). In subgroup analysis, all types of TNFα inhibitors, except for infliximab, demonstrated a significantly lower persistence rate compared with tocilizumab. There was no significant difference in TB incidence between tocilizumab and TNFα inhibitors. In subgroup analysis, infliximab has a significantly higher risk of TB compared with tocilizumab (HR 2.84, p = 0.02).

CONCLUSION

In this analysis, tocilizumab had longer persistence than TNFα inhibitors with a similar incidence of TB. Our analysis has limitations: (1) The HIRA database lacks clinical details like disease activity and joint damage extent, potentially influencing the analysis results. (2) Reasons for discontinuing biological agents were not available. (3) TB diagnoses may be inaccurate because of missing microbiological results. (4) We did not analyze the impact of treating latent TB infection on TB development post-biological treatment, despite mandatory screening in Korea.

Reduced economic disparity in biologics use for psoriasis after introducing the reducing copayment program

Biologics for psoriasis are efficient and safe, but very expensive. We investigated the association of the reducing copayment program (RCP) with changes in biologics use patterns depending on the income levels of patients with moderate-to-severe psoriasis. This nationwide cohort study included patients identified as having moderate-to-severe psoriasis between 2014 and 2020. Logistic regression models were used to estimate the odds ratio for the use of biologics according to income levels. Among 57,139 patients with moderate-to-severe psoriasis, 3464 (6.1%) used biologics for psoriasis from 2014 to 2020. After the introduction of RCP in 2017, the proportion of patients with moderate-to-severe psoriasis using biologics rapidly increased from 5.0% in 2016 to 19.2% in 2020; the increase was more remarkable in patients with the lowest or mid-low income compared to those with Medical Aid. Drug survival of biologics was higher in patients with the highest income before the RCP, but became comparable between those with high and low incomes after RCP introduction. The introduction of RCP was associated with an increased use of biologics in patients with moderate-to-severe psoriasis of all income levels; however, the effect was more pronounced in low-income patients. The RCP may contribute to alleviating the disparity in access to biologics.

Long-term effectiveness and safety of infliximab-biosimilar: A multicenter Phoenix retrospective cohort study

BACKGROUND

Infliximab (IFX) effectively treats patients with inflammatory bowel disease (IBD). IFX-biosimilar (IFX-BS) has the same amino acid sequence as that of the IFX originator, and its increasing use is expected to reduce national healthcare costs. Long-term efficacy and safety of IFX-BS in patients with Crohn's disease (CD) and ulcerative colitis (UC) have not been completely investigated.

METHODS

We conducted a retrospective, multicenter observational study of patients with IBD who received IFX-BS treatment at three hospitals between October 2016 and April 2022. Clinical data were collected from electronic medical records and evaluated for achieving clinical remission (CR) using Crohn's disease activity index (CDAI) and partial Mayo (pMayo) score, persistency of long-term IFX-BS administration, and clinical response rate in the bio-naïve and bio-failure groups.

RESULTS

A total of 117 patients with IBD (90 CD and 27 UC) were included. The study findings indicated that both bio-naïve and bio-failure groups of patients with UC showed similar effectiveness of IFX-BS. The treatment persistence rate in patients with CD was significantly higher in the bio-naïve (P = 0.042) and switch (P = 0.010) groups than in the bio-failure group. In the former two groups, the treatment persistence rate was high at two years after administration (more than 80%). In patients with UC, the findings indicated higher treatment persistence rate in the switch group than in the bio-naïve group. Univariable and multivariable analyses for treatment persistence rate showed that the albumin level at the initial IFX-BS administration and groups (bio-naïve, bio-failure and switch) were effective factors for patients with CD. Adverse events were reported in 18 patients (15.4%).

CONCLUSION

The present study demonstrates the long-term effectiveness and safety of IFX-BS. In addition to the favorable remission induction in the bio-naïve and bio-failure groups, we demonstrated remission maintenance and treatment persistence rates beyond two years. Albumin level and groups were associated with better treatment persistence in patients with CD.

Anticytokine Treatment of Rheumatoid Arthritis: An Observational Report

Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology, characterized by symmetrical arthritis, and deterioration of articular cartilage and epiphyses leading to progressive destruction and deformation of joints, resulting in disability. The purpose of this chapter is to evaluate the effects of treatment with anti-inflammatory biologic medication, Enbrel (Etanercept), during therapeutic rehabilitation in RA patients. The sample comprised 10 hospitalized patients (8 females and 2 males) of the mean age of 32.2 ± 13.4 years treated with Enbrel in 2008-2010. The drug was administered subcutaneously in a dose of 50 mg once a week. Outcomes consisted of differences in the Disease Activity Score (DAS-28) and the degree of joint impairment based on the Health Assessment Questionnaire (HAQ) noted 2 months after treatment onset. The average pre-/post-treatment DAS-28 score was 4.1/2.6, with improvement in 9 patients. The average HAQ score was 1.5/0.6, respectively. We conclude that treatment with Enbrel significantly reduces RA activity and improved joint impairment. The beneficial influence of the drug enabled an earlier commencement of physical rehabilitation, which may have a preventive bearing on the development of disability.