Patiromer enables more persistent use of spironolactone in patients with resistant hypertension and chronic kidney disease (CKD), whether or not they also have type 1 or type 2 diabetes mellitus, according to results from a new AMBER analysis presented during the American Society of Nephrology’s Kidney Week 2020 Reimagined virtual conference.
Of 295 patients in the original AMBER trial, 145 (49%) had diabetes and 150 (51%) did not. Baseline mean serum potassium was 4.76 mEq/L in the diabetes group and 4.67 mEq/L in the group without diabetes. Per protocol, all patients had an estimated glomerular filtration rate of 25 to 45 mL/min/1.73 m2 and systolic blood pressure of 135 to 160 mmHg before randomization.
At 12 weeks, significantly more patients treated with patiromer than with placebo remained on spironolactone therapy whether they had diabetes (83.6% vs 65.3%) or not (87.8% vs 67.1%), respectively, Rajiv Agarwal, MD, of the Indiana University School of Medicine in Indianapolis, Indiana, reported. Patiromer recipients could tolerate a higher cumulative spironolactone dose than placebo recipients: 438.7 mg more in users with diabetes vs 317.8 mg more in users without diabetes. Automated office blood pressure decreased significantly from baseline in patiromer-treated patients with and without diabetes.
Fewer patients taking patiromer than placebo discontinued spironolactone. Hyperkalemia (serum potassium 5.5 mEq/L or greater) occurred less with patiromer, regardless of diabetes status: 41.1% vs 72.2% of patiromer and placebo recipients, respectively, with diabetes and 29.7% vs 56.6%, respectively, of patients without diabetes.
“Results of the primary endpoint in the subgroups with and without [diabetes mellitus] were consistent with those seen in the overall population, with no significant difference between subgroups,” Dr Agarwal said.
Patiromer’s safety profile was consistent with previous reports, including in patients with and without diabetes, he noted. A total of 60% of patiromer users and 61% of placebo recipients with diabetes experienced adverse events compared with 46% and 51%, respectively, of patients without diabetes. Four patients had serum magnesium levels of less than 1.4 mg/dL but none lower than 1.2 mg/dL, including 2 patiromer and 1 placebo recipient with diabetes and 1 patiromer recipient without diabetes. No patient experienced cardiac arrhythmia associated with low magnesium, neuromuscular abnormalities, or serum potassium levels less than 3.5 mEq/L.
Disclosure: This clinical trial was supported by Relypsa, Inc. Please see the original reference for a full list of authors’ disclosures.
Agarwal R, Rossignol P, Arthur S, et al. Patiromer to enable spironolactone in patients with resistant hypertension and CKD (AMBER): results in the prespecified subgroup with diabetes. Presented at: Kidney Week 2020 Reimagined, October 19-25, 2020. Poster SA-OR20.