Skip to main content
The William Harvey Research Institute - Faculty of Medicine and Dentistry

Breadcrumb

  1. WHRI
  2. Clinical Activities
  3. Barts Cardiovascular Clinical Trials Unit (CVCTU)
  4. Completed trials
  5. ORTIZ

ORTIZ

Full Title: ​​A Multi site, placebo controlled, double blind randomised clinical trial evaluating the effectiveness of sodium zirconium cyclosilicate versus placebo to enable safe optimisation of RASi therapy in patients with diabetic kidney disease. ​ 

Short Title: ​​The ORTIZ Study: Optimising RASi Therapy with SZC​

Sponsor: Barts Health NHS Trust

Funder: Astra Zeneca

Chief Investigator: Dr Kieran McCafferty

Contact: kieran.mccafferty4@nhs.net

Registration: https://clinicaltrials.gov/study/NCT04983979

Study Design: Multi-centre, randomised, double-blind, placebo-controlled clinical trial

Objectives:

  • To determine whether 3 months of treatment with sodium zirconium cyclosilicate (SZC) versus placebo enables maximisation of RASi (Irbesartan) therapy in patients with diabetic kidney disease

Number of Participants: 116

Intervention Used: SZC powder for oral suspension

Study Duration: 18 months

Location: Barts Health NHS Trust, Imperial College Healthcare NHS Trust, St George’s University Hospital NHS Trust, King’s College London Hospital NHS Trust

Summary: ORTIZ was a double-blind, placebo-controlled, randomised clinical trial that evaluated whether sodium zirconium cyclosilicate (SZC) enabled safe optimisation of RASi therapy in patients with diabetic kidney disease. Participants received SZC or placebo (powder for oral suspension) for 12 weeks, followed by a 2-week follow-up period.

For patients with diabetes and proteinuria, treatment with RAS inhibitors (RASi) such as ACE inhibitors or angiotensin receptor blockers has been standard care for over two decades. These medications reduce blood pressure and proteinuria, slow kidney function decline, delay dialysis, and protect cardiovascular and renal health. However, their use is often limited by the risk of hyperkalaemia (elevated blood potassium), which can be dangerous due to its effects on heart rhythm. As a result, many patients are unable to tolerate the full therapeutic dose.

SZC is a novel potassium binder that reduces blood potassium levels by binding potassium in the gut. It is recommended by NICE to support RASi dose optimisation in patients with diabetes and kidney disease. ORTIZ aims to assess whether SZC enables patients to tolerate higher doses of Irbesartan, thereby maximising therapeutic benefit.

Back to top