Welcome to the REBOOT Study

The REBOOT study will test whether a combination of two different drugs, belimumab (Benlysta®) and rituximab (Rituxan®), is safe and if this combination is more effective at blocking the immune attack on the kidney in patients with Primary Membranous Neuropathy (MN) compared to rituximab alone.

About the Investigational Study Drug

Rituximab is a medication that works by blocking B cells (an immune cell that is known to have a role in autoimmune diseases like Primary MN). Rituximab is approved by the FDA for use in rheumatoid arthritis, vasculitis, and certain types of cancers. A few studies have shown that rituximab can be effective in treating some people with Primary MN, but is not FDA approved for Primary MN. 

Belimumab is a medication that blocks different types of B cells than rituximab. Belimumab is approved by the FDA for systemic lupus erythematosus (SLE).

REBOOT will investigate whether belimumab, when combined with rituximab, will help remove more B cells than rituximab alone, which may help treat Primary MN. The study will also look at whether belimumab treatment will change the type of B cells that re-grow after treatment with rituximab, which may help Primary MN from coming back.

The combination of belimumab and rituximab is considered experimental for Primary MN.

REBOOT Part A

People with Primary MN lose more protein in their urine because the filters in their kidneys may be damaged. It is possible that some belimumab may also be lost in the urine because of this. To make up for this loss, people with higher levels of protein in their urine may need a higher dose of belimumab than the FDA approved dose. One purpose of Part A is to measure belimumab in the blood to determine if people with more protein in their urine should receive a higher dose of belimumab.

All Part A participants will receive belimumab injections under the skin (subcutaneously) once a week for 1 year. They will also receive an infusion of rituximab at the 4th and 6th week of the study.  Participants will then be followed for an additional 2 years to determine if Primary MN gets better or worse after stopping study treatment.

 

Treatment Phase
(Weeks 0 to 51)

Follow-up Phase
(Weeks 52 to 156)

All Part A Participants

Belimumab weeks 0-51
Rituximab weeks 4 and 6

Follow for safety and Primary MN status

REBOOT Part B

Part B participants will be randomly assigned to 1 of 2 treatment groups. One group will receive weekly subcutaneous belimumab (self-injections under the skin) for 1 year. The other group will receive weekly subcutaneous belimumab placebo (an inactive substance that looks like the drug) for 1 year. All participants will receive intravenous (IV) rituximab at weeks 4 and 6.  Participants will be followed for an additional 2 years to determine if Primary MN gets better or worse after stopping study treatment.

You cannot choose your group. A computer will randomly pick which group you will be in. This study is double-blinded which means that during the study neither you nor your study doctor will know whether you are receiving belimumab or belimumab placebo.

 

Treatment Phase
(Weeks 0 to 51)

Follow-up Phase
(Weeks 52 to 156)

Part B Group 1

Belimumab weeks 0-51
Rituximab weeks 4 and 6

Follow for safety and Primary MN status

Part B Group 2

Belimumab placebo weeks 0-51
Rituximab weeks 4 and 6

Follow for safety and Primary MN status

If Part A shows that people with a higher amount of protein in their urine should receive a higher dose of subcutaneous belimumab, participants with higher urine protein will take 2 belimumab injections per week.