New Therapeutic Approaches for the Treatment of Hyperkalemia in Patients Treated with Renin-Angiotensin-Aldosterone System Inhibitors

Effectiveness, safety, and treatment pattern of sodium zirconium cyclosilicate in Chinese patients with hyperkalemia: interim analysis from a multicenter, prospective, real-world study (Actualize Study)

Introduction: Sodium zirconium cyclosilicate (SZC) is a nonabsorbed cation-exchanger approved in China for the treatment of hyperkalemia [HK; serum potassium (sK+) levels >5.0 mmol/L]. This is the first real-world study aimed to assess the effectiveness, safety, and treatment patterns of SZC in Chinese patients with HK. Here we present the results of the first interim analysis. Methods: This multicenter, prospective, cohort study included patients aged ≥18 years with documented HK within 1-year before study enrollment day. These patients were followed up for 6 months from the enrollment day after initiating SZC treatment. The treatment was categorized into correction phase (FAS-P1) and maintenance phase (FAS-P2 new and ongoing users). Subgroup analysis was performed in patients on hemodialysis (FAS-H). The primary objective was evaluation of safety profile of SZC; secondary objectives included assessment of treatment patterns of SZC and its effectiveness. Results: Of 421 screened patients, 193, 354, and 162 patients were enrolled in the FAS-P1, FAS-P2, and FAS-H groups, respectively. sK+ levels were reduced significantly from 5.9 mmol/L to 5.0 mmol/L after the correction phase. For the maintenance phase, the mean sK+ levels were maintained at 5.2 mmol/L and 5.0 mmol/L in the FAS-P2 new and ongoing user, respectively, and 5.3 mmol/L in the FAS-H subgroup. A considerable proportion of patients showed normokalemia after 48 h of SZC treatment (FAS-P1:51.3%) which was maintained up to 6 months in the maintenance phase (FAS-P2:44%). SZC was well-tolerated. Conclusion: SZC was effective and safe for the treatment of HK in real-world clinical practice in China.

Real-World Modifications of Renin-Angiotensin-Aldosterone System Inhibitors in Patients with Hyperkalemia Initiating Sodium Zirconium Cyclosilicate Therapy: The OPTIMIZE I Study

INTRODUCTION

Hyperkalemia (HK) may result in disruptions of guidelines-concordant renin-angiotensin-aldosterone system inhibitors (RAASi), a standard of care in persons with chronic kidney disease (CKD). Such disruptions-dose reduction or discontinuation-diminish the benefits of RAASi, placing patients at risk of serious events and renal dysfunction. This real-world study evaluated RAASi modifications among patients who initiated sodium zirconium cyclosilicate (SZC) for HK.

METHODS

Adults (≥ 18 years) initiating outpatient SZC (index date) while on RAASi were identified from a large US claims database (January 2018-June 2020). RAASi optimization (maintain same or up-titration of RAASi dosage), non-optimization (down-titration of RAASi dosage or discontinuation), and persistence were descriptively summarized following index. Predictors of RAASi optimization were assessed using multivariable logistic regression models. Analyses were conducted by subgroups, including patients without end-stage kidney disease (ESKD), with CKD, and with CKD + diabetes.

RESULTS

A total of 589 patients initiated SZC during RAASi therapy (mean age 61.0 years, 65.2% male), and 82.7% patients (n = 487) kept RAASi after index (mean follow-up  = 8.1 months). Most patients (77.4%) optimized RAASi therapy after initiating SZC; 69.6% maintained the same dosage while 7.8% had up-titrations. A similar rate of RAASi optimization was observed among subgroups without ESKD (78.4%), with CKD (78.9%), and with CKD + diabetes (78.1%). At 1-year post-index, 73.9% of all patients who optimized RAASi were still on therapy, while only 17.9% of patients who did not optimize therapy were still on a RAASi. Among all patients, predictors of RAASi optimization included fewer prior hospitalizations (odds ratio = 0.79, 95% CI [0.63-1.00]; p < 0.05) and fewer prior emergency department (ED) visits (0.78 [0.63-0.96]; p < 0.05).

CONCLUSION

Consistent with clinical trial findings, nearly 80% of patients who initiated SZC for HK optimized their RAASi therapy. Patients may require long-term SZC therapy to encourage continuation of RAASi therapy especially after inpatient and ED visits.

Hyperkalemia and the Use of New Potassium Binders a Single Center Experience from Vestfold Norway (The PotBind Study)

Purpose

Hyperkalemia is a common metabolic complication of chronic kidney disease (CKD) and is associated with several serious adverse events. We aimed to treat/prevent hyperkalemia using the new of potassium-binders, allowing maintained renin-angiotensin-aldosterone system inhibitors (RAASi) treatment in proteinuric CKD and/or congestive heart failure (CHF) patients.

Patients and Methods

We conducted a retrospective cohort study in long-term users of potassium binders for chronic hyperkalemia. Patients aged 18 years and older, treated with potassium-binders and who met the reimbursement criteria and indication for RAASi treatment were included.

Results

Fifty-seven percent of the patients were males and mean age was 65 years. During the study period, no patients were admitted to hospital due to hyperkalemia after initiation of potassium binders. Potassium maximum values were significantly lower after treatment. Few patients reported major side effects, and discontinuation was mostly due to normokalemia. We found no significant changes in bicarbonate, serum creatinine or GFR stage after starting potassium binder treatment. All patients on RAASi treatment before initiating potassium-binders were retained on RAASi treatment.

Conclusion

New potassium binders in clinical practice are an easy and safe treatment with few side effects and good tolerance, that significantly lowers the risk of hyperkalemia. Furthermore, and most importantly, patients can be maintained on RAASi treatment.

[Recurrent hyperkalaemia management and use of renin-angiotensin-aldosterone system inhibitors: Analysis of French data from the PROKALE multinational European study]

INTRODUCTION

Recurrent hyperkalaemia may result in underutilisation of renin-angiotensin-aldosterone system inhibitors. We report an analysis of French data from the PROKALE retrospective study, which assessed the management of recurrent hyperkalaemia in five European countries.

PATIENTS AND METHODS

A retrospective chart review including patients not on dialysis with two or more hyperkalaemia episodes≥5.5 mEq/L documented within a 12-month observation period was performed.

RESULTS

In France, 115 physicians (57 nephrologists et 58 cardiologists) participated in the study and 295 patients were studied in this analysis. Mean age was 68 years; 212 patients (71.9%) had chronic kidney disease, 108 (36.6%) had chronic heart failure and 102 (34.6%) had diabetes mellitus. The mean number of documented hyperkalaemic episodes was 2.3. A total of 90 hospitalizations occurred during the observation period, of which 24 (26.7%) were directly related to a hyperkalaemic episode. At the time of the first documented hyperkalaemic episode, measures used for the management of hyperkalaemia included loop diuretics (144 patients [48.8%]), sodium/calcium polystyrene sulphonate (135 patients [45.8%]), a low-potassium diet (31 patients [10.5%]) and sodium bicarbonate (31 patients [10.5%]). Between the two consecutive hyperkalaemic episodes documented, the proportion of patients on renin-angiotensin-aldosterone system inhibitors treatment decreased from 42.4% to 34.6%.

CONCLUSION

Renin-angiotensin-aldosterone system inhibitors treatment interruptions were observed in the setting of recurrent hyperkalaemic episodes. Recurrent hyperkalaemia is a major cause of hospitalizations. More effective strategies for the prevention of recurrent hyperkalaemia are needed.

The pharmacotherapeutic management of hyperkalemia in patients with cardiovascular disease

Introduction: Patients with cardiovascular diseases (CVD) are at increased risk of hyperkalemia, particularly when treated with renin-angiotensin-aldosterone inhibitors (RAASIs). Because the occurrence or fear of hyperkalemia, RAASIs are frequently down-titrated or discontinued in patients with CVD, with consequent worse outcomes than patients who remain on maximum doses.Areas covered: This article reviews potassium homeostasis, epidemiology, risk factors, and outcomes of hyperkalemia, and efficacy and safety of the drugs used for acute and chronic treatment of hyperkalemia. A literature search was carried out using the PubMed and guidelines for the management of hyperkalemia.Expert opinion: The emergency treatment of hyperkalemia is not supported by high-quality evidence and clinical trials did not report drug effects on clinical outcomes. Two potassium binders, patiromer and sodium zirconium cyclosilicate, represent a new approach in the treatment of chronic hyperkalemia as they may allow the titration and maintenance of guidelines-recommended doses of RAASIs in patients with CVD who otherwise would not tolerate them due to the risk of hyperkalemia.Further studies are needed to evaluate the safety and efficacy of drug therapy and support the development of guidelines for acute and chronic hyperkalemia.

Clinical Management of Hyperkalemia

Hyperkalemia is an electrolyte abnormality with potentially life-threatening consequences. Despite various guidelines, no universally accepted consensus exists on best practices for hyperkalemia monitoring, with variations in precise potassium (K⁺) concentration thresholds or for the management of acute or chronic hyperkalemia. Based on the available evidence, this review identifies several critical issues and unmet needs with regard to the management of hyperkalemia. Real-world studies are needed for a better understanding of the prevalence of hyperkalemia outside the clinical trial setting. There is a need to improve effective management of hyperkalemia, including classification and K⁺ monitoring, when to reinitiate previously discontinued renin-angiotensin-aldosterone system inhibitor (RAASi) therapy, and when to use oral K⁺-binding agents. Monitoring serum K⁺ should be individualized; however, increased frequency of monitoring should be considered for patients with chronic kidney disease, diabetes, heart failure, or a history of hyperkalemia and for those receiving RAASi therapy. Recent clinical studies suggest that the newer K⁺ binders (patiromer sorbitex calcium and sodium zirconium cyclosilicate) may facilitate optimization of RAASi therapy. Enhancing the knowledge of primary care physicians and internists with respect to the safety profiles of these newer K⁺ binders may increase confidence in managing patients with hyperkalemia. Lastly, the availability of newer K⁺-binding agents requires further study to establish whether stringent dietary K⁺ restrictions are needed in patients receiving K⁺-binder therapy. Individualized monitoring of serum K⁺ among patients with an increased risk of hyperkalemia and the use of newer K⁺-binding agents may allow for optimization of RAASi therapy and more effective management of hyperkalemia.

Safety and Efficacy of Adding Dapagliflozin to Furosemide in Type 2 Diabetic Patients With Decompensated Heart Failure and Reduced Ejection Fraction

Background: Heart failure is the most common cause of hospitalization in elderly patients. It is likely that many of the mechanisms that contribute to reductions in systolic and diastolic function, seen in diabetic patients, place them at an increased risk of heart failure. Diuretic therapy, especially loop diuretics, is the usual way of managing congestion, particularly in volume-overloaded patients. Little is known about the beneficial effect of dapagliflozin when added to loop diuretics in managing patients with decompensated heart failure. Aim: To assess the effect of the addition of dapagliflozin to furosemide in managing decompensated patient with heart failure and reduced left ventricular ejection fraction in terms of weight loss and dyspnea improvement. Patients and Methods: The study included 100 type 2 diabetic patients who were admitted with decompensated heart failure. The study population was randomly divided into two arms. Serum electrolytes and kidney functions were followed up during their hospital stay. Results: With dapagliflozin, there was a statistically significant difference between the two groups regarding the change in body weight and body mass index. The diuresis parameters including urine output, total fluid loss, and fluid balance also showed a statistically significant difference in favor of the use of dapagliflozin, with no significant change in serum potassium or kidney functions. There was significant improvement in patient-reported dyspnea scores with the use of dapagliflozin. Conclusions: Dapagliflozin may provide a new drug option in the treatment of heart failure especially among vulnerable group of diabetics. It had no remarkable effects on serum potassium level and kidney functions. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04385589.

Effects of Sodium-Glucose Co-transporter 2 Inhibition with Empaglifozin on Renal Structure and Function in Non-diabetic Rats with Left Ventricular Dysfunction After Myocardial Infarction

Background

The use of sodium–glucose co-transporter 2 inhibitors (SGLT2i) is currently expanding to cardiovascular risk reduction in non-diabetic subjects, but renal (side-)effects are less well studied in this setting.

Methods

Male non-diabetic Sprague Dawley rats underwent permanent coronary artery ligation to induce MI, or sham surgery. Rats received chow containing empagliflozin (EMPA) (30 mg/kg/day) or control chow. Renal function and electrolyte balance were measured in metabolic cages. Histological and molecular markers of kidney injury, parameters of phosphate homeostasis and bone resorption were also assessed.

Results

EMPA resulted in a twofold increase in diuresis, without evidence for plasma volume contraction or impediments in renal function in both sham and MI animals. EMPA increased plasma magnesium levels, while the levels of glucose and other major electrolytes were comparable among the groups. Urinary protein excretion was similar in all treatment groups and no histomorphological alterations were identified in the kidney. Accordingly, molecular markers for cellular injury, fibrosis, inflammation and oxidative stress in renal tissue were comparable between groups. EMPA resulted in a slight increase in circulating phosphate and PTH levels without activating FGF23–Klotho axis in the kidney and bone mineral resorption, measured with CTX-1, was not increased.

Conclusions

EMPA exerts profound diuretic effects without compromising renal structure and function or causing significant electrolyte imbalance in a non-diabetic setting. The slight increase in circulating phosphate and PTH after EMPA treatment was not associated with evidence for increased bone mineral resorption suggesting that EMPA does not affect bone health.

Electronic supplementary material

The online version of this article (10.1007/s10557-020-06954-6) contains supplementary material, which is available to authorized users.

Potassium binders for chronic hyperkalaemia in people with chronic kidney disease

BACKGROUND

Hyperkalaemia is a common electrolyte abnormality caused by reduced renal potassium excretion in patients with chronic kidney diseases (CKD). Potassium binders, such as sodium polystyrene sulfonate and calcium polystyrene sulfonate, are widely used but may lead to constipation and other adverse gastrointestinal (GI) symptoms, reducing their tolerability. Patiromer and sodium zirconium cyclosilicate are newer ion exchange resins for treatment of hyperkalaemia which may cause fewer GI side-effects. Although more recent studies are focusing on clinically-relevant endpoints such as cardiac complications or death, the evidence on safety is still limited. Given the recent expansion in the available treatment options, it is appropriate to review the evidence of effectiveness and tolerability of all potassium exchange resins among people with CKD, with the aim to provide guidance to consumers, practitioners, and policy-makers.

OBJECTIVES

To assess the benefits and harms of potassium binders for treating chronic hyperkalaemia among adults and children with CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 10 March 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-randomised controlled studies (quasi-RCTs) evaluating potassium binders for chronic hyperkalaemia administered in adults and children with CKD.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risks of bias and extracted data. Treatment estimates were summarised by random effects meta-analysis and expressed as relative risk (RR) or mean difference (MD), with 95% confidence interval (CI). Evidence certainty was assessed using GRADE processes.

MAIN RESULTS

Fifteen studies, randomising 1849 adult participants were eligible for inclusion. Twelve studies involved participants with CKD (stages 1 to 5) not requiring dialysis and three studies were among participants treated with haemodialysis. Potassium binders included calcium polystyrene sulfonate, sodium polystyrene sulfonate, patiromer, and sodium zirconium cyclosilicate. A range of routes, doses, and timing of drug administration were used. Study duration varied from 12 hours to 52 weeks (median 4 weeks). Three were cross-over studies. The mean study age ranged from 53.1 years to 73 years. No studies evaluated treatment in children. Some studies had methodological domains that were at high or unclear risks of bias, leading to low certainty in the results. Studies were not designed to measure treatment effects on cardiac arrhythmias or major GI symptoms. Ten studies (1367 randomised participants) compared a potassium binder to placebo. The certainty of the evidence was low for all outcomes. We categorised treatments in newer agents (patiromer or sodium zirconium cyclosilicate) and older agents (calcium polystyrene sulfonate and sodium polystyrene sulfonate). Patiromer or sodium zirconium cyclosilicate may make little or no difference to death (any cause) (4 studies, 688 participants: RR 0.69, 95% CI 0.11, 4.32; I2 = 0%; low certainty evidence) in CKD. The treatment effect of older potassium binders on death (any cause) was unknown. One cardiovascular death was reported with potassium binder in one study, showing that there was no difference between patiromer or sodium zirconium cyclosilicate and placebo for cardiovascular death in CKD and HD. There was no evidence of a difference between patiromer or sodium zirconium cyclosilicate and placebo for health-related quality of life (HRQoL) at the end of treatment (one study) in CKD or HD. Potassium binders had uncertain effects on nausea (3 studies, 229 participants: RR 2.10, 95% CI 0.65, 6.78; I2 = 0%; low certainty evidence), diarrhoea (5 studies, 720 participants: RR 0.84, 95% CI 0.47, 1.48; I2 = 0%; low certainty evidence), and vomiting (2 studies, 122 participants: RR 1.72, 95% CI 0.35 to 8.51; I2 = 0%; low certainty evidence) in CKD. Potassium binders may lower serum potassium levels (at the end of treatment) (3 studies, 277 participants: MD -0.62 mEq/L, 95% CI -0.97, -0.27; I2 = 92%; low certainty evidence) in CKD and HD. Potassium binders had uncertain effects on constipation (4 studies, 425 participants: RR 1.58, 95% CI 0.71, 3.52; I2 = 0%; low certainty evidence) in CKD. Potassium binders may decrease systolic blood pressure (BP) (2 studies, 369 participants: MD -3.73 mmHg, 95%CI -6.64 to -0.83; I2 = 79%; low certainty evidence) and diastolic BP (one study) at the end of the treatment. No study reported outcome data for cardiac arrhythmias or major GI events. Calcium polystyrene sulfonate may make little or no difference to serum potassium levels at end of treatment, compared to sodium polystyrene sulfonate (2 studies, 117 participants: MD 0.38 mEq/L, 95% CI -0.03 to 0.79; I2 = 42%, low certainty evidence). There was no evidence of a difference in systolic BP (one study), diastolic BP (one study), or constipation (one study) between calcium polystyrene sulfonate and sodium polystyrene sulfonate. There was no difference between high-dose and low-dose patiromer for death (sudden death) (one study), stroke (one study), myocardial infarction (one study), or constipation (one study). The comparative effects whether potassium binders were administered with or without food, laxatives, or sorbitol, were very uncertain with insufficient data to perform meta-analysis.

AUTHORS' CONCLUSIONS

Evidence supporting clinical decision-making for different potassium binders to treat chronic hyperkalaemia in adults with CKD is of low certainty; no studies were identified in children. Available studies have not been designed to measure treatment effects on clinical outcomes such as cardiac arrhythmias or major GI symptoms. This review suggests the need for a large, adequately powered study of potassium binders versus placebo that assesses clinical outcomes of relevance to patients, clinicians and policy-makers. This data could be used to assess cost-effectiveness, given the lack of definitive studies and the clinical importance of potassium binders for chronic hyperkalaemia in people with CKD.

Potassium Intake and Blood Pressure: A Dose-Response Meta-Analysis of Randomized Controlled Trials

Background

Epidemiologic studies, including trials, suggest an association between potassium intake and blood pressure (BP). However, the strength and shape of this relationship is uncertain.

Methods and Results

We performed a meta‐analysis to explore the dose‐response relationship between potassium supplementation and BP in randomized‐controlled trials with a duration ≥4 weeks using the recently developed 1‐stage cubic spline regression model. This model allows use of trials with at least 2 exposure categories. We identified 32 eligible trials. Most were conducted in adults with hypertension using a crossover design and potassium supplementation doses that ranged from 30 to 140 mmol/d. We observed a U‐shaped relationship between 24‐hour active and control arm differences in potassium excretion and BP levels, with weakening of the BP reduction effect above differences of 30 mmol/d and a BP increase above differences ≈80 mmol/d. Achieved potassium excretion analysis also identified a U‐shaped relationship. The BP‐lowering effects of potassium supplementation were stronger in participants with hypertension and at higher levels of sodium intake. The BP increase with high potassium excretion was noted in participants with antihypertensive drug‐treated hypertension but not in their untreated counterparts.

Conclusions

We identified a nonlinear relationship between potassium intake and both systolic and diastolic BP, although estimates for BP effects of high potassium intakes should be interpreted with caution because of limited availability of trials. Our findings indicate an adequate intake of potassium is desirable to achieve a lower BP level but suggest excessive potassium supplementation should be avoided, particularly in specific subgroups.

Efficacy and safety of sodium zirconium cyclosilicate for hyperkalaemia: the randomized, placebo-controlled HARMONIZE-Global study

Aims

Sodium zirconium cyclosilicate (SZC, formerly ZS‐9) is a selective K⁺ binder to treat adults with hyperkalaemia. HARMONIZE‐Global examined the efficacy and safety of SZC among outpatients with hyperkalaemia from diverse geographic and ethnic origins.

Methods and results

This phase 3, randomized, double‐blind, placebo‐controlled study recruited outpatients with serum K⁺ ≥5.1 mmol/L (measured by point‐of‐care i‐STAT device) at 45 sites in Japan, Russia, South Korea, and Taiwan. Following open‐label treatment with thrice‐daily SZC 10 g during a 48 h correction phase (CP), patients achieving normokalaemia (K⁺ 3.5–5.0 mmol/L) were randomized 2:2:1 to once‐daily SZC 5 g, SZC 10 g, or placebo during a 28 day maintenance phase (MP). The primary endpoint was mean central‐laboratory K⁺ level during days 8–29 of the MP. Of 267 patients in the CP, 248 (92.9%) entered the MP. During the CP, mean central‐laboratory K⁺ was reduced by 1.28 mmol/L at 48 h vs. baseline (P < 0.001). During the MP (days 8–29), SZC 5 and 10 g once‐daily significantly lowered mean central‐laboratory K⁺ by 9.6% and 17.7%, respectively, vs. placebo (P < 0.001 for both). More patients had normokalaemia (central‐laboratory K⁺ 3.5–5.0 mmol/L at day 29) with SZC 5 (58.6%) and 10 g (77.3%) vs. placebo (24.0%), with the greatest number of normokalaemic days in the 10‐g group. The most common adverse events with SZC were mild or moderate constipation and oedema.

Conclusions

Normokalaemia achieved during the CP was maintained over 28 days with SZC treatment among outpatients with hyperkalaemia.

Steroidogenic acute regulatory protein/aldosterone synthase mediates angiotensin II-induced cardiac fibrosis and hypertrophy

Aldosterone produced in adrenal glands by angiotensin II (Ang II) is known to elicit myocardial fibrosis and hypertrophy. This study was designed to test the hypothesis that Ang II causes cardiac morphological changes through the steroidogenic acute regulatory protein (StAR)/aldosterone synthase (AS)-dependent aldosterone synthesis primarily initiated in the heart. Sprague-Dawley rats were randomized to following groups: Ang II infusion for a 4-week period, treatment with telmisartan, spironolactone or adrenalectomy during Ang II infusion. Sham-operated rats served as control. Relative to Sham rats, Ang II infusion significantly increased the protein levels of AT1 receptor, StAR, AS and their tissue expression in the adrenal glands and heart. In coincidence with reduced aldosterone level in the heart, telmisartan, an AT1 receptor blocker, significantly down-regulated the protein level and expression of StAR and AS. Ang II induced changes in the expression of AT1/StAR/AS were not altered by an aldosterone receptor antagonist spironolactone. Furthermore, Ang II augmented migration of macrophages, protein level of TGFβ1, phosphorylation of Smad2/3 and proliferation of myofibroblasts, accompanied by enhanced perivascular/interstitial collagen deposition and cardiomyocyte hypertrophy, which all were significantly abrogated by telmisartan or spironolactone. However, adrenalectomy did not fully suppress Ang II-induced cell migration/proliferation and fibrosis/hypertrophy, indicating a role of aldosterone synthesized within the heart in pathogenesis of Ang II induced injury. These results indicate that myocardial fibrosis and hypertrophy stimulated by Ang II is associated with tissue-specific activation of aldosterone synthesis, primarily mediated by AT1/StAR/AS signaling pathways.

Sodium Zirconium Cyclosilicate: A Review in Hyperkalaemia

Sodium zirconium cyclosilicate (Lokelma™) [hereafter referred to as SZC] is a non-absorbed, non-polymer zirconium silicate compound that preferentially exchanges hydrogen and sodium for potassium and ammonium ions in the gastrointestinal tract (GIT), thereby increasing faecal potassium excretion and lowering serum potassium levels. It is available as a powder for oral suspension (in water) and is approved in the EU and the USA for the treatment of hyperkalaemia in adults. In two multinational, phase III studies in adults with hyperkalaemia, SZC 10 g three times daily lowered serum potassium levels to within the normal range (3.5-5.0 mmol/L) during the first 48 h of treatment, and SZC 5 and 10 g once daily maintained normokalaemia over ≤ 28 days' therapy. These beneficial effects were consistent across all patient subgroups (e.g. chronic kidney disease, diabetes, heart failure, concomitant use of RAAS inhibitor therapy), and appeared to be maintained over the longer term (≤ 12 months). SZC was generally well tolerated in adults with hyperkalaemia. Its tolerability profile was generally similar to that seen with placebo over ≤ 28 day, and its safety profile appeared to remain consistent over the longer term (≤ 12 months). Moreover, the incidence of hypokalemia was low. Current evidence indicates that SZC is a promising therapy for the management of hyperkalaemia in adults.