Pharmacokinetics of Zoledronic Acid in Patients on Dialysis (ZADIAL)

September 4, 2026 updated by: Rodrigo Bueno de Oliveira, University of Campinas, Brazil

Pharmacokinetics of Zoledronic Acid in Patients With Chronic Kidney Disease on Dialysis

Osteoporosis is a frequent complication of chronic kidney disease (CKD) on dialysis, with an estimated prevalence of approximately 40%. It is associated with increased fracture risk, reduced quality of life, and higher mortality. Despite available therapies, management often remains suboptimal, partly due to limited evidence on the safety and pharmacokinetics of bisphosphonates in this population. Objectives: To understand the pharmacokinetics of zoledronic acid in CKD patients on dialysis, as well as to analyze its effects on biomarkers of bone metabolism, bone mineral density (BMD), and clinical outcomes. Materials and Methods: This prospective clinical study involves 24 adult individuals, 8 with CKD-associated osteoporosis (control group; estimated glomerular filtration rate (eGFR) ≥ 35 mL/min/1.73 m²) and 16 with CKD-associated osteoporosis anuric on dialysis patients. Individuals undergoing dialysis will be assigned to receive zoledronic acid at doses of 2.5 mg or 5 mg intravenously (single dose, at the beggining of dialysis session), while patients with CKD-associated osteoporosis (control group; estimated glomerular filtration rate (eGFR) ≥ 35 mL/min/1.73 m²) will receive 5 mg, also in a single dose. Serial blood samples will be collected after infusion, during dialysis session and again up to 96h after dialysis session initiation. The dialysate will be continuously sampled in a tank and aliquots collected for further analysis. The plasma levels of zoledronic acid will be calculated from blood and dialysate samples using liquid chromatography mass spectrometry. The primary outcome is the plasma concentration-time curve of zoledronic acid during a regular dialysis session. Secondary outcomes are: (i) plasma concentration of zoledronic acid up to 96h;(ii) the total mass of zoledronic acid extracted by the dialysate; (iii) the dialytic clearance of zoledronic acid. Evaluation of bone biomarkers (e.g., PTH, alkaline phosphatase, calcium, phosphorus, CTX, and P1NP) and BMD (assessed by bone densitometry) will be performed at baseline and at 12 months. The study will be conducted at the UNICAMP Clinical Hospital, with the participation of one participating center, subject to prior approval from the respective Research Ethics Committees. All participants will be included only after signing the Informed Consent Form. Data will be anonymized and processed in accordance with the General Data Protection Law (LGPD). Expected results: To characterize the pharmacokinetic profile and establish the best dosage regimen of zoledronic acid in patients with CKD on dialysis; to observe the impact of the drug on biomarkers of bone metabolism and BMD.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

24

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Rodrigo B de Oliveira, PhD
  • Phone Number: +55 19 35217366
  • Email: rbo@unicamp.br

Study Contact Backup

Study Locations

  • Brazil
    • São Paulo
      • Campinas, São Paulo, Brazil, 13083-887
        • School of Medical Sciences, University of Campinas
        • Contact:
          • Rodrigo B de Oliveira, PhD
          • Phone Number: +55 19 35217366
          • Email: rbo@unicamp.br

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Individuals aged 18 years or older, with CKD-associated osteoporosis
  • eGFR ≥ 35 mL/min/1.73 m2 and advanced CKD on dialysis
  • Agree to participate in the research by signing the informed consent form

Exclusion Criteria:

  • Individuals under 18 years of age, pregnant or breastfeeding women
  • Patients with CKD with hypocalcemia/hypophsphatemia
  • Patients with CKD on dialysis with residual diuresis > 100 mL/24h*
  • Patients with CKD on low-flux membrane dialysis*
  • Patients with neoplasia
  • Hypersensitivity to bisphosphonates, or previous use of the medication
  • Inadequate oral condition or anticipated invasive dental procedure within the next 12 months
  • Alkaline phosphatase < 98 IU/L or > 180 IU/L*
  • PTH < 130 pg/mL and > 585 pg/mL*
  • CTX < Lower Limit of Normal (LLN) or
  • CTX < Upper Reference Limit (URL)*
  • Severe liver disease
  • Severe heart disease
  • Clinical suspiction of osteomalacia or adynamic bone disease
  • Cytopenias, defined as: platelets < 120,000/mm³, neutrophils < 3,000/mm³, lymphocytes < 1,000/mm³ and hematocrit < 26% * Applicable only to the group of patients undergoing dialysis.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Non-Randomized
  • Interventional Model: Sequential Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Control group
CKD-associated osteoporosis in patients with eGFR >= 35 mL/min, allocated to receive conventional dose (5 mg, single dose).
Drug: Zoledronic Acid Injection, 5.0 mg, single dose
Zoledronic Acid Injection, 5.0 mg, single dose for patients with CKD-associated osteoporosis with eGFR >= 35 mL/min.
Drug: Zoledronic Acid Injection, 5.0 mg, single dose
Zoledronic Acid Injection, 5.0 mg, single dose, for patients with CKD-associated osteoporosis on dialysis, at the beginning of dialysis session.
Experimental: CKD_Dialysis_2.5
CKD-associated osteoporosis in patients on dialysis, allocated to receive reduced dose (2.5 mg, single dose), at the beginning of dialysis session.
Drug: Zoledronic Acid Injection, 2.5 mg, single dose
Zoledronic Acid Injection, 2.5 mg, single dose, for patients with CKD-associated osteoporosis on dialysis, at the beginning of dialysis session.
Experimental: CKD_Dialysis_5.0
CKD-associated osteoporosis in patients on dialysis, allocated to receive conventional dose (5 mg, single dose), at the beginning of dialysis session.
Drug: Zoledronic Acid Injection, 5.0 mg, single dose
Zoledronic Acid Injection, 5.0 mg, single dose for patients with CKD-associated osteoporosis with eGFR >= 35 mL/min.
Drug: Zoledronic Acid Injection, 5.0 mg, single dose
Zoledronic Acid Injection, 5.0 mg, single dose, for patients with CKD-associated osteoporosis on dialysis, at the beginning of dialysis session.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Area Under the Curve of zoledronic acid (ng.mL/mL)
Time Frame: From the start of dialysis session to ninety six hours (96 hours) post- drug administration.
Area under the curve of the plasma concentration-time curve of zoledronic acid
From the start of dialysis session to ninety six hours (96 hours) post- drug administration.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Total mass of zoledronic acid extracted by the dialysis
Time Frame: From the dialysis session start to the end of session at four hours (4h)
Zoledronic acid mass (mg)
From the dialysis session start to the end of session at four hours (4h)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Campinas, Brazil

Collaborators

São Paulo State University

Investigators

  • Principal Investigator: Rodrigo B de Oliveira, PhD, University of Campinas

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

August 15, 2026

Primary Completion (Estimated)

August 15, 2027

Study Completion (Estimated)

August 15, 2028

Study Registration Dates

First Submitted

July 16, 2026

First Submitted That Met QC Criteria

July 31, 2026

First Posted (Actual)

August 3, 2026

Study Record Updates

Last Update Posted (Actual)

September 10, 2026

Last Update Submitted That Met QC Criteria

September 4, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 97356426.2.1001.5404

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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