Reata Pharmaceuticals will present promising data of its investigational therapy bardoxolone methyl in the treatment of rare forms of chronic kidney disease, including Alport syndrome, the company announced.
Results of two Phase 2 clinical trials will be presented through four scientific posters during the annual American Society of Nephrology Kidney Week 2018 taking place Oct. 23-28 in San Diego.
Bardoxolone methyl, formerly known as RTA 402, is an oral therapy that works by reducing inflammation and oxidative stress, and restoring the activity of mitochondria (the cells’ powerhouses), potentially improving kidney function.
The presentation, “One-Year Data Report from “CARDINAL”: A Phase 2/3 Study of Bardoxolone Methyl in Patients with Alport Syndrome,” will focus on the one-year data of the open-label, dose-escalating Phase 2 part of the CARDINAL study (NCT03019185), which is evaluating the safety and effectiveness of bardoxolone methyl in 30 Alport patients.
The trial’s primary goal in Phase 2 is the increase in estimated glomerular filtration rate (eGFR) — which assesses the patient’s kidney function — with bardoxolone methyl, compared with levels at the study’s start (baseline).
After one year of bardoxolone treatment, patients undergo a four-week withdrawal period where no therapy is administered, after which, at week 52, treatment is restarted through week 100.
As of May 15, among the 30 enrolled patients, 13 (43%) had received treatment for 48 weeks, and eight patients (26%) had reached the week 52 visit.
At baseline, the patients’ eGFR, or kidney function, was declining at an average annual rate of 4.2 mL/min/1.73 m2.
Bardoxolone methyl treatment for 48 weeks resulted in a significant improvement in kidney function from baseline, with an increase in eGFR of 14 mL/min/1.73 m2. Even with a four-week withdrawal after that, eGFR still remained above the baseline levels, with an increase of 5.6 mL/min/1.73 m2.
The most commonly reported adverse event was mild to moderate muscle spasms, with no evidence of muscle toxicity. At the time of the analysis, no treatment-related adverse events were observed, and no patient had stopped treatment.
These findings showed that “BARD [bardoxolone methyl] was generally well tolerated and produced improvements in kidney function that were sustained for up to one year and remained significantly above baseline following treatment withdrawal,” the researchers wrote.
Phase 3 of the trial is expected to enroll up to 180 Alport patients across more than 60 sites worldwide. Patients will be randomized to receive either bardoxolone methyl or a placebo for one year.
The other three posters will reveal the interim results of the ongoing Phase 2 PHOENIX study (NCT03366337), which is evaluating the safety and effectiveness of bardoxolone methyl in patients with other rare kidney diseases, including autosomal dominant polycystic kidney disease (ADPKD), IgA Nephropathy (Berger’s disease), and chronic kidney disease associated with Type 1 diabetes.
So far, the trial, which is still recruiting, has enrolled 31 patients with ADPKD, 26 with Berger’s disease, and 19 with kidney disease associated with Type 1 diabetes.
Interim results showed that bardoxolone methyl was generally well-tolerated and that it significantly increased the eGFR of patients, ranging from 7.8 mL/min/1.73 m2 to 12 mL/min/1.73 m2 between the three groups.
The researchers noted that while these results suggest durable improvements in patients’ kidney function, additional studies are required to access the long-term effects of bardoxolone methyl on eGFR in patients with these rare chronic kidney diseases.