NCT06918990 · National Institute of Allergy and Infectious Diseases (NIAID)
Treatment of Antibody-Mediated Rejection (ABMR) With CarBel
(CarBel)
What this study is about
The purpose of this study is to see: 1. If using these two drugs (carfilzomib and belatacept) together is safe 2. If the use of these two study drugs in addition to the usual immunosuppression for kidney transplant patients can improve your transplanted kidney function by lowering the antibodies you have against your transplanted kidney 3.
View original scientific description
The purpose of this study is to see: 1. If using these two drugs (carfilzomib and belatacept) together is safe 2. If the use of these two study drugs in addition to the usual immunosuppression for kidney transplant patients can improve your transplanted kidney function by lowering the antibodies you have against your transplanted kidney 3. If the study drugs effect the immune cells that were responding to your donor kidney.
Interventions
BIOLOGICAL
Carfilzomib
Administered by intravenous infusion over 60 minutes.
BIOLOGICAL
Belatacept
Administered by intravenous infusion over 30 minutes.
Primary outcome measures
Proportion of subjects who do not meet a stopping rule for safety and remain free of all of the following: Grade 3 or higher infusion reaction, Grade 3 or higher infections, and any malignancy excluding localized non-melanomatous skin cancer.
Time frame: 3-months post randomization and 12-months post receipt of Investigational Therapy (IT)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Able to understand and agree to participate in the study.
- Have received a kidney transplant from a living or deceased donor (including re-transplants).
- Men and women must agree to use birth control during the study and for 3 months after the last dose of study drugs, or be surgically sterile or post-menopausal.
- Heart function must be good enough (LVEF of at least 40%) without severe heart issues or high blood pressure in the lungs.
- Must have been previously exposed to the Epstein-Barr Virus (EBV).
- Diagnosed with specific types of kidney transplant rejection based on criteria, with certain conditions on timing and treatment history.
- Kidney function must be at a certain level (eGFR of at least 30 ml/min/1.73 m²).
- Patient is ≥6-months post-transplant or is \<6 months post-transplant but has documentation that they have been offered and/or received the local standard of care treatment prior to enrollment.
- Must have a measurable level of specific antibodies against the donor kidney (HLA DSA) with a certain intensity.
- Up-to-date vaccinations according to guidelines for transplant patients.
- Must have a negative tuberculosis (TB) test and chest x-ray before enrollment, no symptoms or known contact with TB, and not have recently traveled to or lived in areas with high TB rates. If previously infected with TB, must have completed treatment and have a recent negative chest x-ray.
- If previously infected with COVID-19, must be fully recovered for at least 21 days before joining the study. No COVID-19 test required for those without symptoms.
Exclusion criteria
- Unable or unwilling to give consent or follow study rules.
- Kidney transplant with incompatible blood types.
- Very high levels of protein in urine, indicating severe kidney issues.
- Previously had a non-kidney organ or bone marrow transplant.
- Any other medical issues that might increase risk, make following the study rules hard, or affect study results, as judged by the study doctor.
- Heart attack within the last year, uncontrolled chest pain, or signs of a recent heart problem on an ECG.
- Severe heart failure (Class 3 or higher).
- Irregular heartbeats that can't be controlled with medication.
- Participants who are actively receiving any of the therapies listed below, or who have previously received these therapies without meeting the required washout period prior to the qualifying biopsy and donor-specific antibody (DSA) assessment:
- ≥4 weeks since last dose: IVIG (intravenous immunoglobulin), therapeutic plasma exchange (TPE)
- ≥6 weeks since last dose: Proteasome inhibitors
- ≥3 months since last dose: Eculizumab; lymphocyte-depleting agents (e.g., rabbit anti-thymocyte globulin, alemtuzumab); anti-CD20 agents
- ≥6 months since last dose: Anti-CD38 agents; anti-IL-6 agents
- Used any experimental drug not specified within the last 4 weeks or longer if the drug stays in the body longer.
- Serious medical or mental health issues that could interfere with the study.
- Cancer diagnosis or treatment within the past 2 years, except for certain skin cancers or cancers with a high cure rate.
- Known allergy to Captisol® (used in the study drug).
- Very low blood counts (hemoglobin, neutrophils, or platelets).
- Positive for HIV, Hepatitis B, or Hepatitis C, unless Hepatitis C was successfully treated.
- Severe infections needing treatment in the last 4 weeks.
- Specific kidney infection (BK nephropathy) or high levels of BK virus.
- Certain kidney biopsy results indicating other types of rejection or kidney diseases.
- Treated for a specific viral infection (CMV) in the last 90 days or resistant to certain CMV treatments.
- Received a live vaccine in the last 4 weeks.
- Severe liver disease or abnormal liver tests.
- Pregnant or breastfeeding women. Women who can become pregnant must have a negative pregnancy test or proof they are not pregnant.
- Any other significant medical condition that could interfere with the study according to the doctor.
- Kidney rejection within 6 months post-transplant without standard care.
- Confirmed severe protein levels in urine.
- Underwent certain treatments from the time of entry DSA result and biopsy screening.
- History of multiple unprovoked blood clots.
- Diagnosed with Atypical Hemolytic Uremic Syndrome (aHUS).
Where
- Birmingham, Alabama
- Phoenix, Arizona
- Los Angeles, California
- Chicago, Illinois
- St Louis, Missouri
- New York, New York
- Durham, North Carolina
- Cincinnati, Ohio
- Cleveland, Ohio
- Madison, Wisconsin
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 10, 2026 · Source of record for eligibility and locations