BERKELEY, Calif., Jan. 7, 2013 (GLOBE NEWSWIRE) -- XOMA Corporation (Nasdaq:XOMA), a leader in the discovery and development of therapeutic antibodies, today announced preliminary top-line data from an interim analysis of its Phase 2 proof-of-concept (POC) study to evaluate the safety and efficacy of gevokizumab, a potent modulator of interleukin-1 beta (IL-1 beta), for the treatment of the inflammatory facial lesions seen in patients with moderate to severe acne vulgaris. The Phase 2 POC study is a double-blind randomized comparison of gevokizumab 0.2mg/kg and 0.6mg/kg versus placebo given subcutaneously once per month for three consecutive months. Investigators have enrolled a total of approximately 125 patients to date, and the interim results are based on up to 92 patients with available data. In line with FDA guidance, inflammatory lesion counts, the primary endpoint in this trial, and overall acne severity as assessed by responder analysis of the Investigator Global Assessment (IGA), defined as at least a two-point improvement on a five-point scale, were measured at different time points up to Day 84. The study was designed to have 80 percent power to detect at least an absolute difference of 15 versus placebo in the mean inflammatory lesion count at Day 84 with statistical significance defined as p≤ 0.10. The 0.6mg/kg dose group showed a statistically significant reduction of 19 in mean inflammatory lesion count on Day 42 compared to a reduction of 13 in the placebo treated group (p=0.077). Each of the groups had a mean baseline of approximately 31 inflammatory lesions. The magnitude of the difference was substantially maintained throughout the study, but differences at later measurement points were not statistically significant. The 0.6mg/kg dose group demonstrated both a clinically and statistically significant improvement in IGA at Day 84, showing a 31 percent responder rate versus a 5 percent responder rate in the placebo group (p= 0.031). The 0.2mg/kg dose group showed no clinically or statistically significant differences from placebo at any time point in inflammatory lesion count or in IGA.