Background/Purpose: The purpose of this study was to
describe the treatment patterns in biologic naïve initiators of TNF-inhibitors
(TNFi) based on their disease activity over a 1-year follow-up period from a
national cohort of patients with rheumatoid arthritis (RA).

Methods: Using data from the Corrona registry, biologic
naïve RA patients were identified between 1/1/2006 and 8/31/2013 who had
initiated their first TNFi (the index date) after any prior use of ≥1 conventional
disease modifying anti-rheumatic drug (cDMARD). The patients were categorized
into disease activity strata defined by the lowest level of disease activity
reached using the Clinical Disease Activity Index (CDAI) across all visits
reported while on TNFi therapy in Corrona during the 1 year follow-up period
including the index date. The mutually exclusive strata are as follows: sustained
remission – attained remission (CDAI ≤2.8) on at least 2 consecutive
visits; remission – attained remission on at least one visit; sustained LDA – remission
was never attained on any visits, but reached low disease activity (LDA; 2.8<
CDAI ≤10) on at least 2 consecutive visits; LDA – attained LDA; and moderate/high
disease activity (MDA/HDA) (CDAI>10) – never achieved remission or LDA on
any visit. Patients were compared on demographics, RA disease characteristics,
and treatment patterns. Comparisons across these disease activity strata were
performed with one-way ANOVA for continuous variables and chi-square test for
categorical variables.

Results: There were 1931 RA patients who met
inclusion criteria of whom 15% achieved sustained remission (n=286), 22%
remission (n=426), 14% sustained LDA (n=271), 23% LDA (n=436) and 27% MDA/HDA
(n=512). The groups differed in terms of demographics (Table 1). Those with
higher levels of disease activity (MDA/HDA) were older at disease onset, had
higher baseline levels of disease activity and greater functional impairment
based on the modified Health Assessment Questionnaire (mHAQ). There were
significant differences between the groups in terms of combination therapy
(Table 1). Higher disease activity was associated with less use of methotrexate
(MTX) based combination therapy (e.g, more use of TNFi monotherapy or combination
therapy with a non- MTX cDMARD). Switching to another TNFi occurred in 14% of
the population, 6.5 to 8.4 months after initiation, on average. At the study
conclusion, 331 (17%) had discontinued TNFi therapy with 99% switching to a
non-TNFi biologic. Those with higher levels of disease activity switched more
frequently to both another TNFi or to a non-TNFi biologic.

Conclusion: Majority of patients (63%) did not
achieve remission or sustained remission. Those in the lower disease activity
strata were more likely to have been prescribed a TNFi with MTX as compared to
MTX monotherapy or in combination with a non-MTX cDMARD, while those with higher
disease activity were more likely to have been switched to another biologic.