Evaluation of a modified ACR20 scoring system in patients with rheumatoid arthritis receiving treatment with etanercept

Objective: To evaluate a modified American College of Rheumatology 20 ( mACR20) scoring system for patients with rheumatoid arthritis. Methods: The data were evaluated from one study on patients with methotrexate ( MTX)- naive early rheumatoid arthritis ( ERA) and another study on patients with DMARD-refractory late rheumatoid arthritis ( LRA). For mACR20 scoring, acute- phase reactant measurements were excluded, and 20% improvement from baseline was determined by 2 or 3 of the 4 remaining ACR components. Results: For full joint counts with data from patients with ERA, marked differences favoured 25 mg etanercept ( ETN) over 10 mg ETN by using the unmodified ACR20 ( 69% v 55%), the mACR20(3 of 4) ( 63% v 49%) and the mACR20(2) (of 4) ( 72% v 58%). An assessment of 28 joints showed similar findings. In the trial on patients with LRA, considerably more patients in both ETN groups achieved a clinical response compared with placebo by using the ACR20, the mACR20(3 of 4) and the mACR20(2 of 4), whether using full or 28 joint counts. The mACR20(3 of 4) and full joint counts with data on patients with ERA showed a marked difference between the MTX and 10 mg ETN groups ( 63% v 49%), which was not observed with the ACR20. Conclusion: Patterns of improvement indicated by mACR20 scores were consistent with standard ACR20 scores.