Background/Purpose: Abatacept (ABT), a T-cell selective costimulatory regulator, went on the market in Japan in September 2010, with a number of reports issued on its effectiveness since. However, no report has been made on the correlation between ABT and rheumatoid factor (RF). We examined the correlation between ABT and RF.

Methods: Among the 143 patients with rheumatoid arthritis who were given ABT at Tsurumai Biologics Communication between September 2010 and August 2011, 89 cases whose RF was measured before and after the ABT administration with week 24 follow-up observation. The subjects were sorted into two groups according to the Simplified Disease Activity Index at week 24 after ABT administration: a good response (GR) group (n=35) that exhibited remission and low disease activity and a poor response (PR) group (n=54) that exhibited moderate and high disease activity. The correlation between the ABT responsiveness and the RF was examined for these groups. In addition, the cases with high disease activity at week zero were selected for a sub-analysis to determine the correlation between the change in disease activity and RF at 24 weeks and the correlation between the effect of ABT and RF at week 24 in terms of the duration of disease, whether or not methotrexate was concurrently used, and the history of pre-biologics administration.

Results: The percentage of men was higher and the disease activity tended to be lower at week zero in the GR group. The RF was 148.5 mg/dl and 341.1 mg/dl at week zero for the GR group and the PR group and 126.8 mg/dl and 194 mg/dl at the 24th week, respectively. In the group consisting only of subjects with high disease activity, the subjects whose disease activity had improved low at week 24 displayed significantly lower RF values at both week zero and week 24 than those whose disease activity had not improved at week 24. The sub-analysis revealed that the bio naive patients who had experienced a crisis less than two years earlier had a significantly lower RF value at week zero and maintained the low level through to week 24. No significant difference was observed in RF change over time between those with and without concurrent methotrexate administration.

Conclusion: We conclude that the lower the RF was at the time of ABT administration, the more effective it was. The RF tended to be lower for the bio naive subjects who had experienced a crisis less than two years earlier. The RF can be a predictive factor for ABT.

---

« Back to 2012 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/correlation-between-abatacept-and-rheumatoid-factor-can-rheumatoid-factor-be-a-predictive-factor-for-abatacept/