Patients with rheumatoid arthritis (RA) who had no prior exposure to biologic disease-modifying antirheumatic drugs (bDMARDs) were more likely to achieve clinical response with abatacept, according to study results published in Arthritis Research & Therapy.
Investigators analyzed data from the Swedish Rheumatology Quality Register, a nationwide clinical register of patients with chronic inflammatory joint diseases, including RA, in Sweden. Patients with RA who began abatacept treatment between April 2006 and November 2017 were included in analyses. Drug survival, defined as time from abatacept initiation to discontinuation, was calculated using the Kaplan-Meier method. Disease activity and abatacept efficacy were evaluated using the Health Assessment Questionnaire Disability Index (HAQ-DI) and Disease Activity Score-28 with C-reactive protein (DAS28-CRP); clinical response to abatacept was defined according to the European League Against Rheumatism (EULAR) criteria. Efficacy outcomes were evaluated at 6 and 12 months. Multivariate regression was performed to identify baseline predictors of abatacept response. Covariates included sex, prior DMARD exposure, baseline methotrexate use, baseline glucocorticoids, baseline DAS28 and HAQ-DI, disease duration, age, and route of abatacept administration.
Data from 2716 patients with RA were included in analyses. Overall, 75% of patients remained on abatacept treatment at 6 months, and 55% remained on the treatment at 12 months. Mean disease course duration at abatacept initiation was 14.2 years, with mean baseline HAQ-DI and DAS28-CRP scores of 1.25 and 4.66, respectively. A total of 17% of patients were bDMARD-naive at baseline, 27% had been exposed to 1 previous bDMARD, and 56% to ≥2 previous bDMARDs. Median drug survival on abatacept was 1.74 years (95% CI, 1.58-1.90 years); 2.23 years (95% CI, 1.69-2.76 years), 1.68 years (95% CI, 1.34-2.01 years), and 1.56 years (95% CI, 1.35-1.76 years) for patients who were bionaive, exposed to 1 previous bDMARD, and exposed to ≥2 previous bDMARDs, respectively. Researchers observed a statistically significant difference in drug survival between bionaive- and bDMARD-experienced patients (P =.001).
Compared with patients who received ≥2 bDMARDs, bionaive patients were less likely to discontinue treatment over time; there was no difference among the subsets of bDMARD-experienced patients.
Multivariate analysis indicated that men were more likely than women to achieve “good” EULAR response at 6 months (adjusted odds ratio [aOR], 2.28; 95% CI, 1.45-3.57) and 12 months (aOR, 2.14; 95% CI, 1.44-3.19). Being bionaive at baseline was also independently associated with good EULAR response at 6 months (aOR, 3.59; 95% CI, 2.25-5.72) and 12 months (aOR, 4.29; 95% CI, 2.77-6.65). Greater HAQ-DI scores, age, and glucocorticoid levels at baseline were negatively associated with good response at both follow-up time points.
Results from the nationwide prospective cohort study identified the absence of prior bDMARD exposure as an independent predictor of abatacept response. According to the investigators, the difference in drug response between men and women with RA warrants further investigation.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Cagnotto G, Willim M, Nilsson J-Å, et al. Abatacept in rheumatoid arthritis: survival on drug, clinical outcomes, and their predictors—data from a large national quality register. Arthritis Res Ther. 2020;22(1):15.