Background/Purpose: : Previous controlled clinical trials have shown that concurrent methotrexate (MTX) therapy may enhance the efficacy of anti-TNF agents. However, real-world data on the benefits of combination therapy with MTX and golimumab (GLM) are scarce. This aim of this analysis was to compare the baseline profile of patients initiating MTX+GLM compared to patients treated with GLM monotherapy and to assess the impact of concomitant MTX treatment on GLM effectiveness.   

Methods: Biologic Treatment Registry Across Canada (BioTRAC) is an ongoing, prospective registry of patients initiating treatment for rheumatoid arthritis, ankylosing spondylitis, or PsA with infliximab or GLM. PsA patients treated with GLM enrolled since 2010 were included in this analysis. Descriptive statistics were produced for clinical outcome measures and patient reported outcomes at baseline, 6 and 12 months of treatment. Within-group changes were assessed for statistical significance with the Wilcoxon t-test. 

Results:

There were 152 PsA patients included in this analysis. Mean (SD) age was 51.3 (13.4) years and disease duration was 4.3 (5.0) years. The majority of patients (94.7%) in the GLM+MTX group received a high MTX dose (≥15 mg/week). 51.8% of patients had a MTX history for the GLM group vs 64.2% for the GLM+MTX group. Baseline patient characteristics and disease parameters were comparable for GLM vs. GLM+MTX although a higher proportion in the GLM group had dactylitis (39.3% vs. 21.1%. P=0.023). Statistically significant and clinically meaningful improvements were observed upon 6 months of treatment in both groups for all disease parameters which were sustained over 12 months of treatment, with the exception of PASI and HAQ-DI in the GLM group which did not reach statistical significance (Table 1). Upon adjusting for baseline levels, patients in the GLM+MTX group experienced greater improvements in most disease parameters although statistical significance was achieved only for TJC.  

Table 1: Disease parameters for GLM vs. GLM+MTX at baseline and 12 months

¹ Represents within group P-value assessed with Wilcoxon test

² Represents between group P-value at 12 months of treatment assessed with linear regression adjusting for baseline disease parameters

The proportion of patients achieving minimal disease activity (MDA) was comparable between groups with GLM=56.0% vs. GLM+MTX=50.0% at 6 months, and GLM=47.1% vs. GLM+MTX=51.4% at 12 months.  

Conclusion: The results of this analysis have shown that treatment with GLM, with or without MTX, is effective in reducing symptom severity and improving disease outcomes over a 12 month period in PsA patients. However, concomitant treatment with MTX may confer additional benefits. Additional analyses with larger sample sizes are required.   

ACR Meeting Abstracts - https://acrabstracts.org/abstract/impact-of-methotrexate-on-the-real-world-effectiveness-of-golimumab-in-psoriatic-arthritis/