In autoimmune disease, rituximab as well as other anti-CD20 antibodies currently being considered for commercialization have focused on a different dosing schedule in rheumatoid arthritis, and use fixed dosages rather than variable doses based on body surface area. In addition, recent studies of these newer anti-CD20 antibodies in rheumatoid arthritis have reported that lower doses indeed appear effective when administered twice, 2 weeks apart. Based upon these considerations, patients in this study will receive hA20 twice, 2 weeks apart, and administered at one of 3 dose levels.