Anti-TNF Therapies Have Changed Remission Rates, Disease Activity in RA

Among patients with rheumatoid arthritis (RA) treated with antitumor necrosis factor (TNF) agents, rates of low sustained remission and low disease activity are significantly different than when anti-TNF therapies were first available, according to research published in Rheumatology.

Researchers investigated the frequency of sustained remission and low disease activity in patients with RA who received treatment with anti-TNF therapies, as well as the predictors associated with these outcomes and how these outcomes have changed over 12 years.

Data were collected from the British Society for Rheumatology Registry for Rheumatoid Arthritis, a national prospective, longitudinal, observational study of the long-term safety of biologic agents. Remission and low disease activity were defined based on Disease Activity Score 28/erythrocyte sedimentation rate thresholds (remission <2.6; low disease activity 2.6 to <3.2).

In total, 14,436 patients with RA were enrolled between 2001 and 2013. Two subgroups were noted: 13,115 patients who registered between 2001 and 2010 and 1321 patients who registered between 2010 and 2013. In the 2001 to 2010 subgroup, anti-TNF therapies were equally split between etanercept, infliximab, and adalimumab; certolizumab was added in 2010.

Among the whole cohort, 14.9% of patients achieved 1 or more instances of sustained remission. Within the subgroups, the proportion of patients achieving remission increased to 21.4% between 2001 to 2010 and 29.6% between 2010 to 2013. Only 26.3% of patients in the whole cohort achieved sustained disease activity; of those patients, 56.4% were also in sustained remission.

Predictors of sustained remission included treatment with adalimumab (vs etanercept), baseline methotrexate therapy, higher patient global assessment scores, and status as a former smoker (vs current smoker). Within the 2001 to 2010 cohort, never-smoker status, higher swollen joint count, and more recent initiation of anti-TNF therapies were also associated with an improved likelihood of sustained remission. In all analyses, poor baseline functional status was the only variable that was linked with a reduced likelihood of achieving sustained remission.

Predictors of sustained low disease activity included baseline methotrexate use, increasing swollen joint count, recent initiation of anti-TNF therapy, and former smoker status, in both the whole cohort and the 2001-2010 subgroup. Additionally, for those in the 2001-2010 subgroup, higher patient global assessment scores were also linked with sustained low disease activity.

Study limitations included the observational nature of the study, potential unidentified selection biases, the differing sample size between the 2 subgroups, and a lack of stratification by anti-TNF agent.

“These results change assumptions about the treatment of [patients with RA] with anti-TNF and show that patients treated in clinical practice today and the associations with sustained remission and [low disease activity] are significantly different from when anti-TNF first became available,” concluded researchers.

Drs Hamann and Hyrich report disclosures. For a complete list, please see the full text of the study online.

Reference

Hamann PDH, Pauling JD, McHugh N, Shaddick G, Hyrich K. Predictors, demographics and frequency of sustained remission and low disease activity in anti-tumour necrosis factor-treated rheumatoid arthritis patients [published online June 1, 2019]. Rheumatology. doi: 10.1093.rheumatology.kez188