A Pilot Study to Assess the Efficacy of Rituximab Therapy in Patients With Treatment Resistant Idiopathic Focal Segmental Glomerulosclerosis (FSGS): Integrating an Assessment of the Relevance of suPAR and Activation of Podocyte β3 Integrin
Overview
- Phase
- Phase 2
- Intervention
- Not specified
- Conditions
- Primary Focal Segmental Glomerulosclerosis
- Sponsor
- Mayo Clinic
- Enrollment
- 9
- Locations
- 4
- Primary Endpoint
- Changes in Proteinuria (With Stable Renal Function)
- Status
- Completed
- Last Updated
- 6 years ago
Overview
Brief Summary
The purpose of this study is to determine whether Rituximab therapy is safe and effective in treating patients with the kidney condition, focal segmental glomerulosclerosis (FSGS), that is no longer responsive to traditional therapies.
Detailed Description
This is a pilot trial to assess the safety, feasibility and efficacy of Rituximab therapy in 20 adult and pediatric patients with either steroid and/or calcineurin inhibitor resistant FSGS or with a significant intolerance or contraindication to the use of these agents. In addition to clinical criteria, elevated levels of suPAR will define inclusion. Changes in the baseline levels of the potential biomarkers (suPAR, as well as activation of beta-3 integrin) in response to treatment will be compared to clinical measures of efficacy. Participants will have a screening/baseline visit to confirm eligibility within 6 weeks prior to the first of two Rituximab infusions (at Day 1 and Day 15). Participants will then attend follow up visits at 1, 3, 6 and 12 months after Rituximab treatment to assess adverse events and collect safety blood and urine samples.
Investigators
Fernando Fervenza
PI
Mayo Clinic
Eligibility Criteria
Inclusion Criteria
- •FSGS involving native kidneys with a diagnostic biopsy performed within the last 3 years
- •Patients \>6 years of age and \< 80 years of age
- •suPAR \> 3500 pg ml-1
- •Treatment with an ACEI and/or ARB as tolerated for at least 3 months prior to enrollment to with a target a systolic blood pressure ≤ 140 mmHg and a diastolic pressure ≤ 90 mmHg in adults and blood pressure readings less than the 95th percentile for age, gender and height in children in at least 75% of readings
- •Proteinuria ≥ 3.0 grams as measured by 24-hour urine collection in adults and urine protein:creatinine ratio ≥ 1.0 in the first morning urine in children, despite ACE inhibitor / ARB treatment as tolerated and a minimum of 8 weeks of prednisone therapy at ≥ 1 mg/kg/day, a trial of calcineurin inhibitor for=\> 3 months or a contraindication/intolerance to such therapy (diabetes, osteoporosis/osteonecrosis, age \>60, BMI ≥35)
- •Negative serum pregnancy test (for women of child bearing age)
- •Men and women of reproductive potential must agree to use an acceptable method of birth control during treatment and for twelve months (1 year) after completion of the trial
- •Able and willing to give written informed consent and comply with study requirements
Exclusion Criteria
- •Estimated GFR \< 40 ml/min per1.73m
- •The rationale is that patients with advanced renal failure may progress rapidly towards ESRD.
- •Collapsing variant of FSGS, as it is rare and has been associated with an aggressive course
- •Concurrent use of immunosuppressive therapy with the exceptions of prednisone 10 mg/day. Patients who are taking other immunosuppressive therapy, must be off immunosuppressive medications for equal to or \> 3 months prior to enrollment into the study with the exception of patients demonstrating significant worsening of proteinuria (of \>30% above baseline) during the washout period. These resistant patients can be treated after 1 month of washout due to the high likelihood of progression and/or lack of delayed (previous) immunosuppression effect.
- •Patients with medical conditions that may cause FSGS (e.g. HIV, lymphoma, heroin use) or have a secondary form of FSGS due to hyperfiltration injury (massive obesity, vesicoureteral reflux, or renal mass reduction)
- •Type 1 or type 2 diabetes mellitus as diabetic glomerulosclerosis may be contributing to proteinuria in these patients
- •History of serious recurrent or chronic infection
- •Presence or suspicion of active infection including TB, HIV, Hepatitis B and HCV with positive tests for Hepatitis B surface antigen (HBsAg), Hepatitis B core antibody (HBcAb), Hepatitis B virus (HBV), Hepatitis C serology, HIV serology or a positive TB skin test, which require further investigation to rule out active disease (ie. chest x-ray)
- •Known active infection requiring hospitalization or treatment with intravenous antibiotics within 4 weeks or oral antibiotics within 2 weeks of the study initiation
- •Low immunoglobulins (level to be based on age)
Outcomes
Primary Outcomes
Changes in Proteinuria (With Stable Renal Function)
Time Frame: Baseline, 12 months
The amount of protein in excreted urine measured by grams per day (g/day). Remission status defined by the following criteria at 12 months: * Complete Remission - Proteinuria \< 0.5 g/day * Partial Remission - Improvement in proteinuria by \> 50% and to a level between 0.5-3.5g/day * Incomplete Remission - Improvement in proteinuria equal to or \>50%, but residual proteinuria still \>3.5g/day
Secondary Outcomes
- Change in Activation of Podocyte β3 Integrin(Baseline, 1, 3, 6, 12 months)
- Change in suPAR Levels(Baseline, 1, 3, 6 and 12 months)
- Number of Subjects With Complete or Partial Remission Following Treatment(12 months)