Welcome to the CALIBRATE Study

The objective of the CALIBRATE study is to determine if treating lupus nephritis with a combination of rituximab (Rituxan®) and cyclophosphamide (Cytoxan®), or a combination of rituximab and cyclophosphamide followed by treatment with belimumab (Benlysta®) is safe and if this drug combination can block the immune system attacks on the kidney.

About the Investigational Study Drugs: Rituximab and Belimumabfalse

Rituximab is a medication that decreases a certain type of immune cell, called B cells, which are known to have a role in autoimmune diseases like lupus nephritis. Once B cells are reduced, the disease may become less active or even inactive. However, the body will make new B cells, and the new B cells may cause your disease to become active again. Belimumab works by decreasing the new B cells your body makes and may even change the type of type of B cells that grow back. Giving belimumab after rituximab could possibly help create changes in the immune system that keep lupus nephritis from coming back. 

Rituximab is approved by the FDA for treating some autoimmune diseases and cancers, but is not approved for lupus nephritis. Belimumab is approved by the FDA for use in treating patients with lupus, but not lupus nephritis. Therefore, the combination of rituximab plus cyclophosphamide and belimumab is considered an experimental treatment and will be evaluated for safety and efficacy in this study.

Participating in the CALIBRATE Study

All participants in the CALIBRATE study will receive intravenous (IV) infusions of Solu-Medrol®, rituximab and cyclophosphamide at weeks 0 and 2. Oral prednisone will be taken daily.

Participants will be randomly assigned to one of two groups at week 4:

  • The Rituximab/Cyclophosphamide (RC) Group, which will continue to take oral prednisone through week 48.
  • The Rituximab/Cyclophosphamide/Belimumab (RCB) Group, which will receive IV belimumab at weeks 4,6,8 and then every 4 weeks through week 48 in addition to prednisone.

You cannot choose your group. A computer randomly picks who receives the study drug.

For those in the RCB group, IV Belimumab will be discontinued after week 48. All participants (RCB and RC groups) will continue to take oral prednisone through week 96. 

The study visits are summarized below:

GROUPTREATMENT PERIOD - 48 weeks (11 months)FOLLOW-UP PERIOD - 48 WEEKS (11 months)
Rituximab/CyclophosphamideIV infusions given at week 0 and 2; Study visits at week 4, 6, 8, and then every 4 weeks through week 48 (no infusions)Visits every 12 weeks (no infusions)
Rituximab/Cyclophosphamide /BelimumabIV infusions given at week 0, 2, 4, 6, 8, and then every 4 weeks through week 48Visits every 12 weeks (no infusions)