ABETIMUS SODIUM AS MAINTENANCE THERAPY FOR LUPUS NEPHRITIS:
PROTOCOL OVERVIEW AND PROGRESS UPDATE FOR THE PHASE 3 ASPEN STUDY

M. Tansey, M.D., M. Linnik, Ph.D (La Jolla Pharmaceutical Company, San Diego, CA, USA)

Objectives: Abetimus sodium (abetimus) is designed to maintain remission in lupus nephritis (LN) by reducing anti-dsDNA antibodies and inducing B cell tolerance. The ASPEN study (Abetimus Sodium in Patients with a History of Lupus Nephritis) is an ongoing study evaluating abetimus at higher doses and in larger numbers of patients than previous studies.

Patients and Methods: Patients must have a diagnosis of systemic lupus erythematosus (SLE), documented SLE renal disease within four years, and anti-dsDNA antibodies ≥ 10 IU/ml (Farr). Patients are excluded if active SLE renal disease occurred within three months prior to randomization and if current immunotherapy and steroid use exceeds defined levels. Patients are randomized 1:1:1 to placebo, abetimus 300 mg, or abetimus 900 mg weekly for 52 weeks. The primary endpoint is time to first renal flare and secondary endpoints include reductions in proteinuria and time to first major SLE flare.

Results and Conclusion: As of 2/11/2008, 607 patients have been enrolled at approximately 130 sites in 23 countries. Interim analysis of anti-dsDNA antibodies at eight weeks demonstrated highly significant dose dependent reductions. The Data Monitoring Board completed two interim safety reviews without identifying any safety issues. The ASPEN study will provide definitive data on the efficacy and safety of abetimus 300 mg/wk and 900 mg/wk in maintenance of remission in LN.

Poster Session
7th European Lupus Meeting
Amsterdam, The Netherlands
May 7, 2008