MRI inflammation may indicate RA patients most suited to combination therapy
medwireNews: Patients with early rheumatoid arthritis (RA) and high levels of inflammation on hand–wrist magnetic resonance imaging (MRI) derive greater benefit from combination therapy than those with low levels of inflammation, study findings indicate.
The post hoc analysis of the phase IIIb AVERT trial showed that patients with high inflammation who received combination therapy were significantly more likely to achieve remission according to a number of disease activity indices than those who received monotherapy.
By contrast, there was no significant difference in remission rates between the two treatment groups for the patients with low inflammation on MRI.
The analysis included data for 225 methotrexate-naïve patients with seropositive early RA (persistent symptoms for ≤2 years) who were randomly assigned to receive abatacept 125 mg/week plus methotrexate 7.5 mg/week, titrated to 15–20 mg/week within 6–8 weeks (n=114) or methotrexate monotherapy (n=111).
On unilateral hand–wrist contrast‐enhanced MRI, 44.7% and 44.1% of patients in the combination and monotherapy groups, respectively, had high levels of inflammation at baseline, defined as synovitis and osteitis in more than three joints, or a combined score of more than nine with osteitis double-weighted due to its greater ability to predict structural damage progression and greater effect on erosion development.
At 12 months, remission rates were significantly higher among the patients who received abatacept plus methotrexate relative to those who received methotrexate alone for the SDAI (≤3.3; 45.1 vs 16.3%), CDAI (≤2.8; 47.1 vs 20.4%), and Boolean scores (tender joint count ≤1, swollen joint count ≤1, CRP ≤1 mg/dL, and patient’s global assessment of disease activity ≤1; 39.2 vs 16.3%).
The proportion of patients achieving DAS28-CRP below 2.6 was also higher with combination therapy versus monotherapy (60.8 vs 40.8%), but not significantly so.
For patients with low inflammation at baseline, the remission rates were numerically, but not significantly, higher in the patients who received abatacept compared with those who did not.
Writing in Arthritis Care and Research, Philip Conaghan (University of Leeds, UK) and co-investigators say their findings show that “abatacept plus [methotrexate] was more effective than [methotrexate] at inducing remission in patients with RA irrespective of baseline levels of MRI inflammation, but that the benefit seen with combination therapy was greater in patients with higher baseline inflammation than in those with lower baseline inflammation.”
They continue: “Thus, we speculate that presence of high MRI inflammation and potentially other poor prognostic factors could be used to risk-stratify patients and determine who might derive the greatest benefit from initiation of abatacept therapy.”
However, the researchers stress that “caution must be exercised during this stratification and MRI inflammation must be considered in the context of other biomarkers in order to prevent suboptimal treatment of patients considered to have a better prognosis (patients with low MRI inflammation).”
By Laura Cowen
medwireNews is an independent medical news service provided by Springer Healthcare. © 2019 Springer Healthcare part of the Springer Nature group