Blog

Understanding Remission: Predictors of Low Disease Activity in Rheumatoid Arthritis Patients Experiencing Inadequate Response to b/tsDMARDS

Objective

🎯 This study aimed to identify predictors of treatment response in patients who previously experienced an inadequate response to a bDMARD or tsDMARD.

Methods

Study design: New-user retrospective cohort study

Data source: OM1 PremiOMTM RA (OM1, Boston, MA), a multisource real-world dataset with linked claims and EHR data on patients with RA in the USA

Study population: Adult patients with moderate-to-severe RA who initiated a b/tsDMARD between January 2013 to June 2024 and had used a different b/tsDMARD in the previous year.

  • Patients had at least 365 days of baseline data available prior to and including the index date

  • Patients had at least one CDAI score >10 in the 90 days prior to and including the index date (baseline), and at least one CDAI score in the 180 days following the index date (follow-up)

  • Initiation of pre-specified b/tsDMARDs of interest: bDMARDs (abatacept, adalimumab, certolizumab, etanercept, golimumab, infliximab, rituximab, sarilumab, tocilizumab) and tsDMARDS (baricitinib, tofacitinib, upadacitinib)

Data Analysis:

  • Primary outcome was LDA (CDAI <10.0) or remission (CDAI <2.8) measured at 6 months post treatment initiation

  • Risk ratios and 95% CI were estimated using log-binomial regression to model the probability of achieving LDA/remission with baseline characteristics as predictors at 6- and 12-months follow-up

  • Predictors included age, sex, race, ethnicity, insurance type, obesity, overweight AND weight-related comorbidity, fibromyalgia, depression, anxiety, COPD, cardiovascular disease, history of type 1 or 2 diabetes, RA disease duration, RF status, anti-CCP status, CRP level, baseline CDAI score, number of prior RA therapies used, prior use of GLP-1 antagonist, corticosteroids, bDMARDS, tsDMARDS, csDMARDS, csDMARDS, and whether the index treatment was a bDMARD vs. a tsDMARD.

  • Estimated CDAI (eCDAI), a validated machine learning algorithm that estimates a patient’s CDAI score using clinical notes,3 was used to supplement missing CDAI scores beyond 6 months of follow-up.

Results

  • At the 6-month follow-up, the mean CDAI decreased from 24.3 to 17.6, with 31.0% of patients achieving LDA/remission after 6 months of follow-up.

  • Patients who achieved LDA/remission at 6 months were more likely to be White, have commercial insurance, reside in the Northeast, have a lower BMI, and less likely to be overweight or have a weight-related comorbidity.

  • Patients who achieved LDA/remission at 6 months were more likely to have moderate disease activity, have RA for ≥2 years, and less likely to have comorbidities, including fibromyalgia.

  • Patients with obesity, osteoporosis, COPD, fibromyalgia, higher baseline CDAI scores, or those who initiated bDMARDs (vs. tsDMARDs) were less likely to achieve LDA/remission at 6 months.

Multivariable associations of baseline characteristics on achieving LDA/remission at 6-month follow-up.

Statistical significance is denoted by values in bold red

C-Statistic=0.65 (A measure of the model’s ability to classify subjects achieving LDA at 6 months)

Note: The statistical significance observed for the ‘Unknown’ race category and CRP levels <3 mg/L may be influenced by missing data. Similarly, key laboratory variables such as RF status and anti-CCP status also had missing data. As a result, interpretation of findings related to these variables is limited and warrants caution.

Conclusion

  • In this large real-world study of patients with moderate-to-severe RA and prior inadequate response to biologic/targeted synthetic DMARDs, over two-thirds (69%) and approximately two-thirds (≈63%) of those who started a new b/tsDMARDs failed to achieve low disease activity/remission at 6- and 12-month follow-up, respectively.

  • Patients with obesity, comorbidities such as COPD, fibromyalgia, and osteoporosis, higher baseline CDAI scores, and those treated with bDMARDs (vs. tsDMARDs) at index were less likely to achieve LDA/remission after 6 months of follow-up. Similar results for obesity and other comorbidities were observed at the 12- month follow-up.

  • These findings highlight the significant impact of obesity and comorbidities on the clinical management of RA, aligning with the ACR guidelines, which recommend maintaining a healthy weight to optimize long-term RA outcomes.5

  • Future research should explore the interaction between comorbidities and RA disease activity to enable targeted interventions that improve outcomes.

Poster & Supplemental Materials

View the full poster and supplemental materials here.

References

  1. Jahid M, et al. Mediterr J Rheumatol. 2023;34(3):284–291.

  2. Deson S., Int. J. Clin. Rheumatol. 2024;19(6):208–210.

  3. Spencer AK, et al. RMD Open. 2021;7(3):e001781.

  4. FDA, 2025. Obesity and Overweight: Guidance for Industry. Available at:

    https://www.fda.gov/media/71252/download

  5. England BR, et al. Arthritis Rheumatol. 2023;1299–1311.



Related articles

See all