Effect of a CCR5 antagonist on clinical, inflammatory, and bone remodeling processes of collagen-induced arthritis (CIA). CIA was induced in 10 susceptible rhesus monkeys. One group of five animals received prophylactic treatment with the low-molecular-weight CCR5 antagonist SCH-X twice daily for 45 days by intramuscular injection, while a second group of five animals received saline solution for the same period. Treatment was started on the day of CIA induction. Results are expressed as the mean maximum change (± standard deviation), which was deduced from the highest measured increase or decrease of the depicted parameter relative to the start of treatment. The figure shows a significant effect (Student's t-test; P < 0.05) of SCH-X treatment on serum levels of C-reactive protein (CRP) (a), albumin (c), and alkaline phosphatase (AP) (d), as well as the excretion rates of hydroxylysylpyridinoline (HP) (e) and lysylpyridinoline (LP) (f). The effect on body weight (b) was not statistically significant. Histology confirmed the lower-joint destruction in the group treated with SCH-X (see ref ).