A Study Exploring the Safety, Tolerability and Efficacy of a 4 Week Course of INCB018424 in Subjects With Active Rheumatoid Arthritis

The ACR 20 is defined as ≥ 20% improvement in tender joint count plus ≥ 20% improvement in swollen joint count plus ≥ 20% improvement in 3 of the following 5 criteria: subject's assessment of pain, Subject's global assessment of disease activity (PGA), Physician's global assessment of disease activity (PHGA), subject's self-assessed disability Health Assessment Questionnaire (HAQ), and Erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP), whichever shows the greatest change.

The ACR 50 is defined as ≥ 50% improvement in tender joint count plus ≥ 50% improvement in swollen joint count plus ≥50% improvement in 3 of the following 5 criteria: subject's assessment of pain, PGA, PHGA, subject's self-assessed disability HAQ, and ESR or CRP, whichever shows the greatest change.

The ACR 70 is defined as ≥ 70% improvement in tender joint count plus

≥ 70% improvement in swollen joint count plus ≥ 70% improvement in 3 of the following 5 criteria: subject's assessment of pain, PGA, PHGA, subject's self-assessed disability HAQ, and ESR or CRP, whichever shows the greatest change.

Calculation of the disease activity score 28 (DAS 28) score was based on the tender joint count, plus swollen joint count, plus PGA, plus Erythrocyte sedimentation rate (ESR). The DAS28-ESR is expressed as units on a scale with the minimum score=0 (best) to maximum score=10 (worst). Remission was defined as DAS28-ESR <2.6. The mean change from baseline (which represent decreases in the DAS 28 ESR scores) are shown as positive numbers in these analyses.

Calculation of the disease activity score 28 (DAS 28) score was based on the tender joint count, plus swollen joint count, plus PGA, plus C-reactive protein (CRP). A higher score indicated more disease activity. The mean change from baseline (which represent decreases in the DAS 28 CRP scores) are shown as positive numbers in these analyses. The DAS28 provides a score on a scale from 0 to 10 indicating the current activity of the rheumatoid arthritis (>5.1=high disease activity; <3.2=low disease activity; <2.6=remission).

Subjects who achieved low disease activity based on the DAS 28 ESR (score <3.2). Subjects who achieved low disease activity were classified as responders in this analysis.

Subjects who achieved low disease activity based on the DAS 28 CRP (score <3.2). Subjects who achieved low disease activity were classified as responders in this analysis.

Subjects who achieved inactive disease based on the DAS 28 ESR (score <2.6). Subjects who achieved low disease activity were classified as responders in this analysis.

Subjects who achieved inactive disease based on DAS 28 CRP (score <2.6). Subjects who achieved low disease activity were classified as responders in this analysis.