ClinicalTrials.gg
CompletedNCT07348536REMOV-HDxUpdated Nov 10, 2026

Expanded Hemodialysis Versus High-Volume Online Hemodiafiltration for Uremic Toxin Removal

An interventional study of Expanded Hemodialysis With Medium Cut-Off Membrane and High-Volume Online Hemodiafiltration in End Stage Renal Disease (ESRD), Chronic Kidney Disease on Hemodialysis and Renal Dialysis, sponsored by Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. Completed at 1 site in Mexico. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-10.

Sponsored by Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran · Not applicable, Interventional, and Treatment

Updated Nov 10, 2026Now CompletedPrimary completion moved+2 moreGo to Updates ↓
Phase
Not applicable
Study type
Interventional
Enrollment
15
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

People with advanced kidney disease need dialysis to remove waste products from the blood. Some of these waste products, called uremic toxins, are small, while others are medium-sized and more difficult to remove. Poor removal of these toxins may contribute to symptoms and long-term complications in patients on dialysis.

Two dialysis techniques are commonly used to improve toxin removal beyond standard hemodialysis: expanded hemodialysis (HDx) using medium cut-off membranes, and high-volume online hemodiafiltration (HV-OL-HDF). Although both techniques are effective, the best way to prescribe expanded hemodialysis-particularly the ideal treatment time-has not been clearly defined.

The purpose of this study is to compare how well different treatment times of expanded hemodialysis remove small and medium-sized uremic toxins, and to compare these results with high-volume online hemodiafiltration. Toxin removal will be evaluated using a combined measurement called the Global Removal Score, which summarizes the removal of several important waste substances.

This is a single-center, randomized, open-label, crossover study. Adults receiving maintenance hemodialysis will receive three different expanded hemodialysis sessions with different treatment durations (180, 210, and 240 minutes), followed by one session of high-volume online hemodiafiltration. Blood samples will be taken before and after each dialysis session to measure toxin levels.

The results of this study may help determine whether expanded hemodialysis with shorter or standard treatment times can achieve toxin removal similar to high-volume hemodiafiltration, which could support more personalized and practical dialysis prescriptions.

Read the detailed description

Expanded hemodialysis (HDx) using medium cut-off (MCO) membranes has been developed to improve the removal of medium-sized uremic toxins while maintaining effective clearance of small solutes. These medium-sized molecules have been associated with inflammation, cardiovascular disease, and other complications in patients with end-stage kidney disease. High-volume online hemodiafiltration (HV-OL-HDF) is currently considered a reference therapy for enhanced removal of these toxins, but its use may be limited by technical requirements, vascular access constraints, or resource availability.

While expanded hemodialysis has shown removal efficiency comparable to high-volume hemodiafiltration in prior studies, the optimal prescription of HDx-particularly the appropriate treatment duration-has not been clearly established. In routine clinical practice, dialysis dose is commonly guided by small-solute clearance (such as urea), which may not fully reflect the removal of medium-sized uremic toxins. A more comprehensive evaluation of toxin removal may help optimize dialysis prescriptions and improve treatment personalization.

This study is designed to compare the efficiency of uremic toxin removal across different expanded hemodialysis treatment durations and to contrast these results with high-volume online hemodiafiltration. Removal efficiency will be assessed using the Global Removal Score, a composite measure that integrates the removal rates of several small and medium-sized molecules while accounting for albumin loss.

The study is a single-center, randomized, open-label, crossover trial conducted in adult patients receiving maintenance hemodialysis. Each participant will receive three expanded hemodialysis sessions with different treatment durations (180, 210, and 240 minutes), administered in randomized sequences following the long interdialytic interval. After completion of the three expanded hemodialysis sessions, all participants will undergo one session of high-volume online hemodiafiltration with a predefined convective volume target.

During each study session, blood samples will be collected immediately before and after dialysis to measure concentrations of selected uremic toxins, including small solutes and medium-sized molecules. These measurements will be used to calculate individual and global removal rates for each dialysis modality and treatment duration. Standard dialysis parameters will be maintained according to institutional practice to ensure patient safety and consistency across sessions.

The crossover design allows each participant to serve as their own control, reducing variability related to patient-specific factors. The primary analysis will compare global toxin removal between expanded hemodialysis prescriptions and high-volume online hemodiafiltration, as well as across different HDx treatment durations.

The findings of this study may help clarify whether expanded hemodialysis with shorter or standard treatment times can achieve toxin removal comparable to high-volume hemodiafiltration. This information could support more individualized dialysis prescriptions and inform clinical decision-making in settings where high-volume hemodiafiltration is not feasible or routinely available.

02

Conditions studied

  • End Stage Renal Disease (ESRD)
  • Chronic Kidney Disease on Hemodialysis
  • Renal Dialysis
  • Uremia; Chronic
  • Hemodialysis
  • Hemodiafiltration

Keywords

  • Expanded hemodialysis
  • High-volume online hemodiafiltration
  • Medium cut-off dialysis membranes
  • Uremic toxin removal
  • Middle molecule clearance
  • Chronic kidney failure
  • Dialysis dose optimization
  • Dialysis treatment time
  • Global removal score
03

In context

Kidney Failure, Chronic

2,108 studies on the registry are indexed under Kidney Failure, Chronic; 273 are open to participants now.

This study's enrollment of 15 is below the median of 57 across 1,569 interventional studies indexed under Kidney Failure, Chronic.

Browse Kidney Failure, Chronic studies →

Lead sponsor

Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran is the lead sponsor of 144 studies on the registry; 16 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Adults aged 18 years or older
  • End stage renal disease Receiving maintenance hemodialysis three times per week on expanded hemodialysis as part of routine care for at least 1 month
  • On dialysis treatment for more than 3 months
  • Minimal or no residual urine output (less than 100 mL per day)
  • Able and willing to provide written

Exclusion criteria

Exclusion Criteria:

  • Vascular access unable to support a blood flow of at least 300 mL/min
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
15 participants (actual)

Study arms

  • Experimental
    Expanded Hemodialysis Prescriptions and High-Volume Online Hemodiafiltration

    Participants will receive three expanded hemodialysis sessions with different treatment durations (180, 210, and 240 minutes) in randomized order, followed by one session of high-volume online hemodiafiltration. Blood samples will be collected before and after each session to assess uremic toxin removal.

    Device: Expanded Hemodialysis With Medium Cut-Off Membrane · Device: High-Volume Online Hemodiafiltration

Interventions

  • DeviceExpanded Hemodialysis With Medium Cut-Off Membrane

    Expanded hemodialysis will be performed using a medium cut-off dialysis membrane designed to enhance the removal of medium-sized uremic toxins while preserving albumin. Treatments will be delivered during regularly scheduled dialysis sessions with fixed dialysate flow and the maximum blood flow tolerated by the participant. Each participant will receive expanded hemodialysis sessions with three different treatment durations (180, 210, and 240 minutes), administered in randomized order following the long interdialytic interval. Blood samples will be collected before and after each session to assess removal of small and medium-sized uremic toxins.

    Also known as: Expanded hemodialysis, Medium cut-off hemodialysis

  • DeviceHigh-Volume Online Hemodiafiltration

    High-volume online hemodiafiltration will be delivered using post-dilution substitution during a standard dialysis session. Treatment will target a predefined convective volume consistent with high-volume hemodiafiltration while maintaining standard dialysis safety parameters. This intervention will be administered once to each participant after completion of the expanded hemodialysis sessions. Blood samples will be collected before and after the session to measure removal of small and medium-sized uremic toxins for comparison with expanded hemodialysis.

    Also known as: Online hemodiafiltration, High-volume hemodiafiltration, Post-dilution online hemodiafiltration

06

What researchers measure

Primary outcomes

  1. Global Removal Score of Uremic Toxins

    The Global Removal Score is a composite measure of dialysis efficiency that summarizes the percentage reduction of selected small and medium-sized uremic toxins during a dialysis session. It is calculated using the reduction ratios of urea, beta-2 microglobulin, myoglobin, prolactin, alpha-1 microglobulin, and alpha-1 acid glycoprotein, adjusted for albumin loss. Higher values indicate greater overall uremic toxin removal.

    Time frame: During each dialysis intervention session (pre- and post-dialysis measurements), over a 4-week study period

Secondary outcomes

  1. Removal Rate of Individual Medium-Sized Uremic Toxins

    Percentage reduction of individual medium-sized uremic toxins, including beta-2 microglobulin, myoglobin, prolactin, alpha-1 microglobulin, and alpha-1 acid glycoprotein, measured before and after each dialysis session.

    Time frame: During each dialysis intervention session (pre- and post-dialysis measurements), over a 4-week study period

  2. Removal Rate of Small Solutes

    Percentage reduction of small solutes, including urea and creatinine, measured before and after each dialysis session to assess small-molecule clearance across dialysis modalities and treatment durations.

    Time frame: During each dialysis intervention session (pre- and post-dialysis measurements), over a 4-week study period

  3. Beta-2 Microglobulin Clearance by Kt/V

    Dialysis dose for beta-2 microglobulin expressed as Kt/V, calculated for each dialysis session to compare the kinetics of beta-2 microglobulin removal across expanded hemodialysis prescriptions and high-volume online hemodiafiltration.

    Time frame: During each dialysis intervention session, over a 4-week study period

07

Study locations

1 site
08

References and documents

Individual participant data

Plan to share: No — Individual participant data will not be shared publicly. This study involves a small, single-center cohort with detailed clinical and laboratory data, and sharing individual-level data could increase the risk of participant re-identification. In addition, the data are collected for a specific mechanistic research purpose and are not intended for secondary analyses outside the scope of the approved protocol. Aggregate results will be reported through scientific publications and presentations.

No publications or documents are linked to this record.

09

Timeline

1 registry update since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedDate before it movedWhere the date was before it movedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Apr 2026 to primary completion in Nov 2026, 7 months.

Of 347 non-industry interventional studies with no phase under Kidney Failure, Chronic, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 47. This study's 7 months is below that.

Counting every sponsor, half of 425 studies reached it within 23 months; a quarter within 8 and three quarters within 46.

Since we started tracking on Sep 25, 2026, the dates moved once, on Nov 10, 2026: primary completion Apr 2026 → Nov 2026 and completion Dec 2029 → Nov 2026.

Earlier changes are on the record history on ClinicalTrials.gov ↗

How these figures are worked out, and which studies are left out of them.

Registered
Dec 22, 2025
First posted
Jan 16, 2026
StartActual
Apr 1, 2026
Primary completionActual
Nov 1, 2026was Apr 2026
CompletionActual
Nov 1, 2026was Dec 2029
Last update
Nov 10, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
Status
Not yet recruiting→Completed
changed Nov 10, 2026
Primary completion
Apr 2026→Nov 1, 2026 (actual)
Nov 10, 2026
Study completion
Dec 2029→Nov 1, 2026 (actual)
Nov 10, 2026
Show all 1 update
  1. Nov 10, 2026
    Not yet recruiting→Completed
    Primary completion Apr 2026→Nov 1, 2026 (now actual)
    Study completion Dec 2029→Nov 1, 2026 (now actual)
    + 1 other change: contact details

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT07348536
Responsible party
Olynka Vega (Principal investigator, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran) — Principal investigator
First posted
Jan 16, 2026
Start date
Apr 1, 2026
Primary completion
Nov 1, 2026
Completion
Nov 1, 2026
Last update
Nov 10, 2026

Study contacts

Olynka Vega, MS
principal investigator · Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.

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