Table 2.

Mean changes in serum anti-cyclic citrullinated peptide (CCP) and rheumatoid factor (RF) levels

	Abatacept	Placebo
Serum anti-CCP (U/ml)
Baseline (month 6 analysis)*	227.6 (289.8)	145.5 (98.2)
Month 6*	133.1 (198.2)	161.9 (155.3)
Mean change from baseline to month 6 (95% CI)*	−94.5 (−156 to −33.0)	16.3 (−28.8 to 61.5)
Baseline (year 1 analysis)†	270.0 (325.4)	212.9 (131.3)
Year 1†	263.5 (430.0)	362.4 (314.2)
Mean change from baseline to year 1 (95% CI)†	−6.5 (−110 to 97.4)	149.5 (3.8 to 295.1)
Serum RF (U/ml)
Baseline (month 6 analysis)‡	167.5 (249.8)	63.5 (92.0)
Month 6‡	42.4 (46.3)	61.5 (82.9)
Mean change from baseline to month 6 (95% CI)‡	−125 (−218 to −32.1)	−2.0 (−15.4 to 11.5)
Baseline (year 1 analysis)§	137.0 (212.1)	54.9 (51.5)
Year 1§	96.3 (109.7)	47.1 (53.9)
Mean change from baseline to year 1 (95% CI)§	−40.7 (−133.0 to 51.3)	−7.8 (235.2 to 19.6)

^*n=21 and 19;

^†n=14 and 10;

^‡n=22 and 20;

^§n=15 and 10, for abatacept and placebo, respectively.