A Phase 2/3 Trial of the Efficacy and Safety of Bardoxolone Methyl in Patients With Alport Syndrome - CARDINAL

This international, multi-center, Phase 2/3 trial will study the safety, tolerability, and efficacy of bardoxolone methyl in qualified patients with Alport syndrome. The Phase 2 portion of the trial will be open-label and enroll up to 30 patients. The Phase 3 portion of the trial will be double-blind, randomized, placebo-controlled and will enroll up to 180 patients.

Patients in the Phase 2 cohort will receive bardoxolone methyl throughout the study. Patients in the Phase 3 cohort will be randomized 1:1 to either bardoxolone methyl or placebo and randomization will be stratified by baseline albumin to creatinine ratio (ACR). Patients randomized to placebo will remain on placebo throughout the study, undergoing sham titration.

All patients in the study will follow the same visit and assessment schedule. Following randomization on Day 1, patients will be scheduled to be assessed during treatment at Weeks 1, 2, 4, 6, 8, 12, 24, 36, 48, 52, 64, 76, 88, 100, and 104 and by telephone contact on Days 3, 10, 21, 31, 38, and 45. Patients will not receive study drug during a 4-week withdrawal period between Weeks 48 and 52. They will re-start treatment at Week 52 at the same dose they received at Week 48 and will continue study drug treatment through Week 100. Patients will also be scheduled to be assessed at an in person follow up visit at Week 104, four weeks after the end of treatment.

Inclusion criteria

• Male and female patients 12 ≤ age ≤ 60 upon study consent;
• Diagnosis of Alport syndrome by genetic testing (documented mutation in a gene associated with Alport syndrome, including COL4A3, COL4A4, or COL4A5) or histologic assessment using electron microscopy;
• Screening eGFR ≥ 30 and ≤ 90 mL/min/1.73 m2. The two eGFR values collected at Screen A and Screen B visits used to determine eligibility must have a percent difference ≤ 25%;
• Albumin to creatinine ratio (ACR) ≤ 3500 mg/g at Screen B visit;
• If receiving an angiotensin-converting enzyme (ACE) inhibitor and/or an angiotensin II receptor blocker (ARB), the medications must remain the same for at least 6 weeks prior to the Screen A visit and during Screening. The dosage of ACE inhibitor and/or ARB must also be stable for 2 weeks prior to the Screen A visit and remain the same through Day 1 (i.e., no change in dosage or medication). Patients not taking an ACE inhibitor and/or ARB because of a medical contraindication must have discontinued treatment at least 8 weeks prior to the Screen A visit;
• Adequate bone marrow reserve and organ function at the Screen A visit
• Able to swallow capsules;
• Willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures;

Exclusion criteria

• Prior exposure to bardoxolone methyl;
• Ongoing chronic hemodialysis or peritoneal dialysis therapy;
• Renal transplant recipient;
• B-type natriuretic peptide (BNP) level > 200 pg/mL at Screen A visit;
• Uncontrolled diabetes (HbA1c > 11.0%) at Screen A visit;
• Acute dialysis or acute kidney injury within 12 weeks prior to Screen A visit or during Screening;
• Serum albumin < 3 g/dL at Screen A visit;
• History of clinically significant left-sided heart disease and/or clinically significant cardiac disease, including but not limited to any of the following:
• Uncontrolled systemic hypertension as evidenced by sitting systolic blood pressure (BP) > 160 mm Hg or sitting diastolic BP > 100 mm Hg at Screen A visit after a period of rest;
• Systolic BP < 90 mm Hg at Screen A visit after a period of rest;
• History of malignancy within 5 years prior to Screen A visit, with the exception of localized skin or cervical carcinomas;
• Systemic immunosuppression for more than 2 weeks, cumulatively, within the 12 weeks prior to randomization or anticipated need for immunosuppression during the study;
• Untreated or uncontrolled active bacterial, fungal, or viral infection;
• Participation in other interventional clinical studies within 30 days prior to Day 1;
• Unwilling to practice acceptable methods of birth control (both males who have partners of child-bearing potential and females of childbearing potential) during Screening, while taking study drug, and for at least 30 days after the last dose of study drug is ingested;
• Women who are pregnant or breastfeeding;
• Known hypersensitivity to any component of the study drug