Objectives: Predicted versus observed radiographic progression in early rheumatoid arthritis (POPeRA) was applied to demonstrate how various treatment modalities affect and potentially minimise radiographic progression over time.
Methods: The POPeRA method utilises the baseline radiographic score and patient-reported symptom duration to predict radiographic outcomes. It was applied at baseline, 2, and 5 years to patients with eRA from the randomised Finnish RA Combination trial (FIN-RACo) (n=144) and New Finnish RA Combination Therapy (NEO-RACo) (n=90) trials. For FIN-RACo, patients were randomised either to a single DMARD (sulfasalazine, with or without prednisolone) or to combination therapy (methotrexate+sulfasalazine+hydroxychloroquine, i.e. triple therapy, with prednisolone). In NEO-RACo, all patients were assigned intensified combination therapy (including 7.5 mg prednisolone/day) plus a randomised 6-month induction of either placebo or anti-TNF treatment (infliximab).
Results: In FIN-RACo, combination versus monotherapy resulted in superior outcomes in the change from predicted progression over 2 and 5 years (mean 35.7% reduction vs. -32.9%, a worsening from predicted, p=0.001; 34.2% vs. -17.8%, p=0.003, respectively). In NEO-RACo, combination+anti-TNF induction led to significantly greater reductions from predicted progression than combination+placebo, both at 2 and 5 years of follow-up (98.5% vs. 83.4%, p=0.005; 92.4% vs. 82.5%, p=0.027, respectively). Importantly, anti-TNF add-on led to superior reductions from predicted among RF-positive patients (2 years: 97.4% vs. 80.4%, p=0.009; 5 years: 90.2% vs. 80.1%, p=0.030), but not among RF-negative patients.
Conclusions: These results confirm that conventional combination therapy in eRA has a long-term radiographic benefit versus monotherapy. Through POPeRA, it was made evident that anti-TNF induction therapy for 6 months further increases the long-term radiographic benefit of combination therapy in RF-positive patients.