Groundbreaking Korean Study Proves Expanded Hemodialysis Preserves Kidney Function - First Global Evidence for HDx Benefits

Revolutionary Breakthrough in Dialysis Treatment

Korean medical researchers have achieved a groundbreaking milestone in nephrology by becoming the first in the world to scientifically prove that expanded hemodialysis (HDx) can effectively preserve residual kidney function in dialysis patients. This landmark study, published in the prestigious Journal of the American Society of Nephrology (JASN), represents a paradigm shift in how we approach dialysis treatment for end-stage kidney disease patients.

The research team from Kyungpook National University Hospital and Kyungpook National University Chilgok Hospital has provided compelling evidence that expanded hemodialysis using the Theranova dialyzer significantly slows the decline of remaining kidney function compared to conventional high-flux dialysis membranes. This discovery has profound implications for the millions of dialysis patients worldwide who struggle with progressive loss of their residual kidney function.

What makes this study particularly significant is that it represents the first randomized controlled trial to demonstrate the clinical effectiveness of expanded hemodialysis in preserving residual kidney function. Previous studies had shown promising results for toxin removal, but this Korean research team has now proven that HDx technology can actually help patients maintain their natural kidney function for longer periods.

Understanding the THREAD Study: Methodology and Participants

The THREAD (Theranova Randomized Expanded hemodialysis And residual kiDney function) study was conducted across four major hospitals in Korea, with Kyungpook National University Hospital and Kyungpook National University Chilgok Hospital serving as the primary research centers. The study enrolled 80 patients who had recently been diagnosed with end-stage kidney disease and were beginning long-term hemodialysis treatment.

Led by Professor Kim Yong-rim and Professor Cho Jang-hee from Kyungpook National University Hospital's Department of Nephrology, along with Professor Lim Jeong-hoon from Kyungpook National University Chilgok Hospital, the research team designed a rigorous 12-month randomized controlled trial. Patients were randomly assigned to receive either expanded hemodialysis using the Theranova 400 dialyzer or conventional treatment with high-flux dialysis membranes.

The study protocol involved comprehensive monitoring of residual kidney function and serological changes at three-month intervals throughout the 12-month period. Researchers measured glomerular filtration rate (GFR) and 24-hour urine volume as primary indicators of residual kidney function, while also tracking various biomarkers related to kidney injury and inflammation.

Remarkable Clinical Results: HDx Shows Superior Kidney Protection

The results of the THREAD study were nothing short of remarkable, demonstrating clear superiority of expanded hemodialysis in preserving residual kidney function. Patients treated with the Theranova dialyzer showed a significantly slower rate of kidney function decline compared to those receiving conventional high-flux dialysis treatment.

Specifically, the Theranova group experienced an average annual decline in glomerular filtration rate (GFR) of only 1.0 mL/min/1.73 m² per year, while the high-flux dialysis group saw a much steeper decline of 2.4 mL/min/1.73 m² per year. This represents more than a 50% reduction in the rate of kidney function loss, which could translate to years of additional kidney function for patients.

The benefits extended beyond just GFR measurements. The Theranova group also maintained better 24-hour urine volume until the 9-month mark, indicating superior preservation of the kidneys' ability to produce urine and maintain fluid balance. Additionally, researchers observed more effective removal of middle-molecular uremic toxins and inflammatory cytokines in the expanded hemodialysis group, while maintaining stable albumin levels throughout the study period.

Global Medical Community Reactions and Expert Opinions

The international nephrology community has responded with considerable enthusiasm to these groundbreaking findings. The study's publication in JASN, one of the most prestigious journals in nephrology with an impact factor of 9.4, underscores the significance of these results for the global medical community.

Professor Christopher McIntyre from London Health Sciences Centre, who served as the symposium chair when these results were presented at the 45th Korean Society of Nephrology conference, emphasized the clinical importance of these findings. The research has been recognized as providing the first scientific evidence for expanded hemodialysis effectiveness in a real-world clinical setting.

Medical experts have particularly praised the study's rigorous methodology and its focus on Korean patients, which provides directly applicable evidence for Asian populations. The research has been selected as one of the top 30 outstanding R&D achievements in healthcare for 2025, highlighting its potential impact on clinical practice. International dialysis specialists note that this study fills a critical gap in evidence-based medicine for expanded hemodialysis therapy.

Understanding Residual Kidney Function: Why It Matters for Patient Survival

Residual kidney function represents the remaining natural kidney capacity that patients retain even after starting dialysis treatment. This remaining function is measured through glomerular filtration rate and daily urine output, and its preservation has been consistently linked to improved patient outcomes across multiple clinical studies.

Research has shown that patients who maintain higher levels of residual kidney function experience significantly better survival rates, reduced cardiovascular disease risk, improved nutritional status, and enhanced overall quality of life. The continuous nature of natural kidney function provides benefits that intermittent dialysis cannot fully replicate, particularly in removing protein-bound toxins and maintaining fluid balance.

The importance of preserving residual kidney function has been well-established in peritoneal dialysis patients, but evidence for hemodialysis patients has been more limited. This Korean study now provides compelling evidence that expanded hemodialysis can help hemodialysis patients maintain their residual kidney function for longer periods, potentially translating to improved long-term outcomes and survival.

Theranova Technology: The Science Behind Expanded Hemodialysis

The Theranova dialyzer represents a significant technological advancement in dialysis treatment, featuring a unique asymmetric triple-layer medium cut-off (MCO) membrane structure. This innovative design enables more effective removal of large middle-molecular uremic toxins that conventional high-flux dialysis and hemodiafiltration struggle to eliminate, while minimizing albumin loss.

Expanded hemodialysis using Theranova combines both diffusion and convection mechanisms in a hollow-fiber dialyzer, allowing for enhanced clearance of molecules up to 45 kDa in size. This expanded solute removal profile addresses the limitations of conventional dialysis, which typically only removes small molecules and smaller middle molecules effectively.

Clinical studies have consistently demonstrated that Theranova-based expanded hemodialysis achieves superior removal rates for β2-microglobulin, myoglobin, and free light chains compared to standard high-flux membranes. The technology maintains stable plasma albumin levels while significantly improving the clearance of uremic toxins that contribute to cardiovascular complications and other long-term dialysis-related morbidities.

Future Implications for Dialysis Treatment Strategies

The THREAD study results are expected to influence dialysis treatment protocols worldwide, particularly in how clinicians approach the preservation of residual kidney function. Professor Cho Jang-hee, the study's lead author, emphasized that residual kidney function plays a crucial role in electrolyte regulation, fluid balance, and ultimately patient mortality outcomes.

Healthcare systems are now considering how to integrate expanded hemodialysis into standard treatment protocols, particularly for newly diagnosed dialysis patients who typically have substantial residual kidney function. The economic implications are also significant, as preserving kidney function longer could reduce healthcare costs through decreased hospitalization rates and improved patient outcomes.

Dr. Kuljinder Singh from Baxter Asia-Pacific Medical Affairs noted that this research demonstrates the real clinical benefits that expanded hemodialysis can provide to dialysis patients. The company has committed to continuing clinical research to expand the evidence base for HDx therapy and its role in improving patient quality of life and extending survival. As the global dialysis population continues to grow, these findings offer hope for better treatment outcomes and improved long-term prognosis for kidney disease patients worldwide.