Background: Hyperkalemia occurs frequently in diabetes. Sodium zirconium cyclosilicate (SZC), an oral, selective potassium (K) binder, rapidly reduces K in patients (pts) with hyperkalemia and has been shown to maintain normokalemia for up to 1 y. We compared the response to SZC in adults with and without diabetes mellitus (DM, type 1/2) in a 12 month, global, multicenter, single arm study (N=751; NCT02163499).

Methods: K was measured in serum or whole blood by iSTAT. During the correction phase (CP), pts received 10 g SZC TID (24–72 h) until iSTAT K 3.5–5.0 mmol/L was achieved. During the maintenance phase (MP), pts with iSTAT K 3.5–5.0 mmol/L received SZC titrated to K ≤5.0 mmol/L (5 g to start, min 5 g QOD, max 15 g QD) for ≤1 y. There were no diet or RAASi use restrictions. Mean K and AEs were compared between pts with and without DM.

Results: At baseline (BL), DM (n=468) vs non-DM pts (n=278) were heavier (mean 90.0 vs 79.9 kg); older (mean 64.7 vs 61.9 y); had worse renal function (mean eGFR 40.4 vs 58.2, with 83.7% vs 59.2% having eGFR <60 mL/min/1.73 m2); more hypertension (89.5% vs 71.6%) and prior edema (34.2% vs 15.1%); and received more RAASi (70.5% vs 54.6%), diuretics (50.4% vs 24.8%), and other drugs. Both groups had comparable K at BL (mean serum and iSTAT K 5.6 and 5.5 mmol/L, respectively). In CP, 81.4% and 82.8% of pts with and without DM, respectively, achieved iSTAT K ≤5.0 mmol/L by 24 h. At 72 h, >99% pts in each group achieved mean iSTAT K 3.5–5.0 mmol/L. MP was completed by 60.5% and 65.8% pts and mean (SD) SZC doses were 7.4 (2.6) and 6.9 (2.6) g in those with and without DM. More DM (43.6%) vs non-DM (31.3%) pts received the 10 g SZC QD dose over the 12 months, at last dose. By day 8, mean increases in bicarbonate from CP BL were 1.07 and 0.77 mmol/L. Overall for months 3–12, 88.3% vs 88.5% achieved a mean serum K ≤5.1 mmol/L; rates were 97.8% vs 96.3% for iSTAT K. Normokalemia was maintained up to 12 months (Figure), at which time mean iSTAT K was 4.50 and 4.45 mmol/L. In MP, 72.6% vs 53.6% had ≥1 AE and 27.6% vs 11.5% had ≥1 serious AE. Common AEs (>5%) were hypertension, oedema, urinary tract infection, nausea, constipation, anemia, upper respiratory tract infection, vomiting, and acute renal failure, all of which were more common in DM pts. Sixty-three (13.5%) DM and 24 (8.6%) non-DM pts had edema or peripheral edema, most of which were mild.

Conclusions: In both DM and non-DM pts with hyperkalemia, SZC rapidly reduced K and maintained normokalemia for up to 1 y. AE profiles were consistent with prior studies and pts’ comorbid conditions.

IMAGE 1: