Phase IV, Double-Blind, Placebo-Controlled, Randomized-Withdrawal Trial Evaluating Sodium Zirconium Cyclosilicate (SZC) for the Management of Hyperkalaemia in Patients With Symptomatic Heart Failure With Reduced Ejection Fraction and Receiving Spironolactone
Trial Snapshot
- Phase
- Phase 4
- Status
- Completed
- Sponsor
- AstraZeneca
- Enrollment
- 366
- Locations
- 1
- Primary Endpoint
- Participants Who Achieved Response, Defined as Serum Potassium (sK+) Within 3.5 to 5.0 mEq/L, Spironolactone Greater Than or Equal to 25 mg Daily, no Rescue Therapy for Hyperkalaemia
Study Overview
Brief Summary
The main objective of this study is to evaluate the efficacy of SZC as compared with placebo in keeping potassium levels within the normal range (3.5-5.0 mEq/L) while on spironolactone ≥25 mg daily without assistance of rescue therapy for hyperkalaemia (HK).
Detailed Description
REALIZE-K is a Phase 4, multinational, multicenter, double-blind, placebo-controlled, randomized-withdrawal, parallel-group study that includes the following 3 phases: screening, 4-6 week open-label run-in phase where sodium zirconium cyclosilicate (SZC) and spironolactone will be optimized, followed by a 6-month double-blind, placebo-controlled, randomized withdrawal treatment phase.
Patients meeting the following criteria will enter the 4-6 week open-label run-in phase: symptomatic heart failure with reduced ejection fraction (HFrEF); receiving an angiotensin-converting enzyme inhibitor (ACEi), angiotensin II receptor blocker (ARB), or angiotensin receptor-Neprilysin inhibitor (ARNi); receiving no spironolactone or eplerenone, or receiving low-dose spironolactone (<25 mg daily); receiving a beta-blocker unless contraindicated; AND with hyperkalemia (sK+ 5.1-5.9 mEq/L) and an eGFR >/= 30 mL/min/1.73m2, OR normokalemic (sK+ 3.5-5.0 mEq/L) and 'at risk' of developing hyperkalemia (ie, history of hyperkalemia within the past 36 months and eGFR >/= 30 mL/min/1.73m2, or sK+ 4.5-5.0 mEq/L and eGFR 30-60 mL/min/1.73m2 and/or age >75 years).
Patients who are normokalemic on SZC and receiving spironolactone >/= 25 mg daily at the end of the open-label run-in phase will enter the 6-month double-blind, placebo-controlled, randomized withdrawal treatment phase. Eligible patients will be randomized 1:1, stratified by run-in phase sK+ cohort.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Double (Participant, Investigator)
Masking Description
All participants entering the double-blind, randomised treatment period will be centrally assigned to randomised study intervention using an Interactive Response Technology/Randomisation and Trial Supply Management (IRT/RTSM). Randomisation will be stratified by the sK+ cohort determined by central laboratory at the start of the open-label phase (Day 1). Before the study is initiated, the telephone number and call-in directions for the IRT and/or the log in information and directions for the RTSM will be provided to each site.
The IRT/RTSM will provide to the investigator(s) or pharmacists the kit identification number to be allocated to the participant at the dispensing visit. Routines for this will be described in the IRT/RTSM user manual that will be provided to each centre.
The randomisation code should not be broken except in medical emergencies when the appropriate management of the participant requires knowledge of the treatment randomisation.
Eligibility Criteria
- Ages
- 18 Years to 130 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Arms & Interventions
Open-label run-in phase
Cohort 1 (4 weeks duration): Patients who are hyperkalemic at study entry will begin SZC 10 g TID for up to 48 hours followed by SZC 10 g once daily to achieve and maintain normokalemia. The SZC dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Cohort 2 (up to 6 weeks duration): Patients who develop hyperkalemia during the uptitration of spironolactone will receive SZC 10 g TID for up to 48 hours followed by SZC 10 g once daily to achieve and maintain normokalemia. The SZC dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Intervention: Sodium zirconium cyclosilicate (Drug)
Open-label run-in phase
Cohort 1 (4 weeks duration): Patients who are hyperkalemic at study entry will begin SZC 10 g TID for up to 48 hours followed by SZC 10 g once daily to achieve and maintain normokalemia. The SZC dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Cohort 2 (up to 6 weeks duration): Patients who develop hyperkalemia during the uptitration of spironolactone will receive SZC 10 g TID for up to 48 hours followed by SZC 10 g once daily to achieve and maintain normokalemia. The SZC dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Intervention: Placebo (Drug)
Open-label run-in phase
Cohort 1 (4 weeks duration): Patients who are hyperkalemic at study entry will begin SZC 10 g TID for up to 48 hours followed by SZC 10 g once daily to achieve and maintain normokalemia. The SZC dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Cohort 2 (up to 6 weeks duration): Patients who develop hyperkalemia during the uptitration of spironolactone will receive SZC 10 g TID for up to 48 hours followed by SZC 10 g once daily to achieve and maintain normokalemia. The SZC dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Intervention: Spironolactone (Other)
Randomized withdrawal phase (6 months)
SZC arm and Placebo arm: Patients will continue on the SZC dose they were receiving at the end of the run-in phase.
The SZC / Placebo dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Intervention: Sodium zirconium cyclosilicate (Drug)
Randomized withdrawal phase (6 months)
SZC arm and Placebo arm: Patients will continue on the SZC dose they were receiving at the end of the run-in phase.
The SZC / Placebo dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Intervention: Placebo (Drug)
Randomized withdrawal phase (6 months)
SZC arm and Placebo arm: Patients will continue on the SZC dose they were receiving at the end of the run-in phase.
The SZC / Placebo dose will be adjusted as needed to maintain normokalemia (dose range = 5 g every other day, to 5-15 g once daily).
Intervention: Spironolactone (Other)
Outcomes
Primary Outcomes
Participants Who Achieved Response, Defined as Serum Potassium (sK+) Within 3.5 to 5.0 mEq/L, Spironolactone Greater Than or Equal to 25 mg Daily, no Rescue Therapy for Hyperkalaemia
Time Frame: From Month 1 (Visit 9) to Month 6 (Visit 14), up to 6 months
The median percentages of participants having a response are presented. Response means all three requirements were met. Non-response was indicated for participants lost to follow-up, including death. The treatment effect was analysed using a generalised estimating equation (GEE) model with a binomial family and a log link, a dependent variable of response per visit, fixed independent variables of randomised treatment, subject recruitment country, a per visit indicator variable and open-label period cohort. The common odds ratio was derived together with two-sided 95% confidence intervals.
Secondary Outcomes
- Participants Who Achieved Response, Defined as sK+ Within 3.5-5.0 mEq/L, on the Same Dose of Spironolactone as Randomisation, no Rescue Therapy for Hyperkalaemia(From Month 1 (Visit 9) to Month 6 (Visit 14), up to 6 months)
- Participants Who Achieved Response, Defined as Spironolactone Greater Than or Equal to 25 mg Daily(From Month 1 (Visit 9) to Month 6 (Visit 14), up to 6 months)
- Time to First Hyperkalaemia (sK+ Greater Than 5.0mEq/L) Episode(From randomisation to the end of treatment (EOT) visit, up to 6 months)
- Time to First Instance of Decrease or Discontinuation of Spironolactone Dose Due to Hyperkalaemia(From randomisation to the EOT visit, up to 6 months)
- Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS) at EOT(At EOT visit (approximately 6 months post-randomisation))
