Patrick Nachman, MD | University of Minnesota

Ignacio Sanz, MD | Emory University

University of Alabama at Birmingham | Birmingham, AL

Stanford University | Stanford, CA

The Lundquist Institute | Torrance, CA

Mayo Clinic Jacksonville | Jacksonville, FL

National Institutes of Health Clinical Center | Bethesda, MD

University of Minnesota | Minneapolis, MN

Columbia University | New York, NY

University of North Carolina | Chapel Hill, NC

Ohio State University | Columbus, OH

University of Pennsylvania | Philadelphia, PA

Providence Medical Research Center | Spokane, WA

REBOOT is a two-part clinical study of adults with primary membranous nephropathy that will investigate whether belimumab and rituximab is safe and more effective at blocking the immune attack on the kidneys compared to rituxumab alone

Part A is an open-label PK (pharmacokinetic) study to compare belimumab exposure between participants who have "low" proteinuria between 4-8g/day and "high" proteinuria more than 8g/day. If belimumab exposure levels is not comparable between the low and high proteinuria groups, the belimumab dose will be increased for participants with high proteinuria during Part B of the study. Participants in Part A will also receive rituxumab.

Part B is a prospective, randomized, phase II, double-blind, placebo-controlled, multicenter clinical trial in adults with primary membranous nephropathy. Participants will be randomized to two treatment arms. Both arms will receive rituximab at weeks 4 and 6. Participants in the experimental arm will receive belimumab weekly for 52 doses. Participants in the control arm will receive a weekly placebo in the place of belimumab. After 52 weeks, all participants will be followed on no study medication and then assessed for the primary endpoint of complete remission at week 104 and at week 156 to determine if treatment with belimumab and rituximab results in a more durable remission than rituximab alone.