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Active, Not Recruiting

NCT Number: NCT04972552

Watermelon/UBIQuinone Study

The objective of the proposed pilot trial is to determine the feasibility and safety of increasing watermelon consumption, with or without coenzyme Q supplementation in patients after kidney transplantation on kidney function and urinary protein excretion.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

Kidney Transplantation

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of California San Francisco

San Francisco, California, 94143, United States

About this study

While many observational studies have examined the effects of consuming watermelon in patients without chronic kidney disease, there have been few studies on the consumption of a diet high in watermelon as a means of improving kidney function or reducing protein in the urine. Coenzyme Q is also recognized as a supplement that has benefits for heart health and has anti-oxidative effects, but whether it could be used to improve kidney function or reduce protein in the urine has not been thoroughly examined, especially in the kidney transplant population. The objective of the proposed pilot trial is to determine the feasibility and safety of increasing watermelon consumption, with or without coenzyme Q supplementation in patients after kidney transplantation.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 18 years of age or older
  • Received a kidney transplant in the last four weeks
  • History of dialysis dependency prior to kidney transplant
  • Able to provide informed consent
  • Not currently consuming a high-watermelon diet or taking co-enzyme Q10
  • Not underweight (body mass index <19 kg/m2)
  • Not enrolled in any other interventional trial
  • Planning to return for follow-up at UCSF (or willing to return for study visits)

Exclusion criteria

  • < 18 years of age at the time of transplant
  • Preemptive transplantation
  • Unable to provide informed consent

Treatment and study plan

Coenzyme Q10

Dietary Supplement

Participants will take 800-1200 mg of coenzyme Q10 capsule per day

Other names: CoQ10

Watermelon diet

Other

Participants will be asked to eat watermelon at a minimum of one meal per day 3-5 days a week

Usual diet

Other

Participants will be asked to eat a usual diet but not eat any watermelon as part of their usual diet

Placebo

Other

Participants will be asked to take 800-1200 mg of a placebo capsule per day

Primary outcomes

  1. Number of patients who complete the study after randomized assignment

    Time frame: Measured at the 20 weeks mark

    We will determine the number of patients who drop out of the study following randomized assignment

  2. Number of participants who develop adverse safety events (including low systolic blood pressure or hyperkalemia) during participation in the study

    Time frame: Measured from 0-20 weeks

    We will measure the number of patients who develop low blood pressure and high potassium levels (hyperkalemia) following randomized assignment. Low blood pressure will be defined as systolic blood pressure < 90 mmHg; hyperkalemia will be defined as serum potassium > 5.5 meq/L

Secondary outcomes

  1. Mean change in weight from baseline to 20 weeks

    Time frame: Baseline to 20 weeks

    We will check for a change in weight, measured in kg, at the start and end of the intervention period.

  2. Changes in amount of protein excretion in the urine over a 20-week period

    Time frame: Baseline to 20 weeks

    We will check for a change in urine protein/creatinine ratio (g/g) at the start and end of the intervention period.

  3. Proportion of participants with an eGFR < 60 mL/min/1.73 m2

    Time frame: Baseline to 20 weeks

    We will assess kidney function outcomes at week 20

  4. Amount of interstitial fibrosis and tubular atrophy

    Time frame: At 20 weeks (cross-sectional)

    We will compare the degree of interstitial fibrosis or tubular atrophy (as a percentage on a biopsy specimen) based on kidney biopsy results.

Sponsors and collaborators

Lead sponsor

University of California, San Francisco

Other

Registry information

Official study title

Watermelon/UBIQuinone Study (WUBI-Q Trial)

Acronym: WUBI-Q

Important dates

Study start
2021
Primary completion
2025
Study completion
2026
First posted
Jul 22, 2021
Registry last updated
Jul 14, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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