Kidney Week

Abstract: SA-PO765

Mechanism of Action of Veverimer, a First-in-Class, Orally Administered, Nonabsorbed, Counterion-Free Hydrochloric Acid Binder for the Treatment of Metabolic Acidosis in CKD

Session Information

• CKD: Mechanisms - III
  November 09, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 2103 CKD (Non-Dialysis): Mechanisms

Authors

• Shao, Jun, Tricida, Inc., South San Francisco, California, United States

Jun Shao,

• Biyani, Kalpesh N., Tricida, Inc., South San Francisco, California, United States

Kalpesh N. Biyani,

• Kade, Matthew, Tricida, Inc., South San Francisco, California, United States

Matthew Kade,

• Kierstead, Paul, Tricida, Inc., South San Francisco, California, United States

Paul Kierstead,

• Gbur, Randi, Tricida, Inc., South San Francisco, California, United States

Randi Gbur,

• Tabakman, Scott, Tricida, Inc., South San Francisco, California, United States

Scott Tabakman,

• Nguyen, Son H., Tricida, Inc., South San Francisco, California, United States

Son H. Nguyen,

• Buysse, Jerry M., Tricida, Inc., South San Francisco, California, United States

Jerry M. Buysse,

• Klaerner, Gerrit, Tricida, Inc., South San Francisco, California, United States

Gerrit Klaerner,

Background

Current management of metabolic acidosis in patients with CKD relies on dietary protein restriction to reduce metabolic acid production or neutralization of retained acid with orally administered bicarbonate. Veverimer is being developed to provide a novel treatment modality for metabolic acidosis: endogenous acid removal. Veverimer is a free-amine polymer designed to combine high capacity and high selectivity for binding and removing HCl from the GI tract. It does not deliver sodium or other counterions and may therefore be appropriate for all patients with CKD and metabolic acidosis, including those with common sodium-sensitive comorbidities.

Methods

The binding capacity of veverimer and its selectivity for chloride over other anions were assessed in vitro in matrices mimicking the pH and ionic conditions of the human GI tract. Proof-of-concept of the efficacy of veverimer to increase serum bicarbonate was provided using a rat model of adenine-induced nephropathy and chronic metabolic acidosis. The bioavailability of veverimer was assessed in ADME studies in rats and dogs dosed with ¹⁴C-labeled veverimer.

Results

In vitro, veverimer had a maximum binding capacity of 10.7 ± 0.4 mmol HCl per gram of polymer with significant binding capacity (> 5 mmol/g) across the entire range of physiologically relevant human GI pH (1.5 to 7). Upon protonation, veverimer bound chloride with high specificity, with little to no binding of phosphate, citrate or taurocholate. Administration of veverimer to rats with adenine-induced nephropathy and chronic metabolic acidosis resulted in a significant increase in fecal chloride excretion and a dose-dependent increase in serum bicarbonate to within the normal range, compared to untreated controls. ADME studies demonstrated that veverimer was not absorbed from the GI tract into the systemic circulation.

Conclusion

Endogenous acid removal through binding to veverimer, an orally-administered, non-absorbed polymer that is then excreted, provides a potential new mechanism for treating metabolic acidosis in patients with CKD.

Funding

• Commercial Support –