ClinicalTrials.gg
Status unknownNCT05269615Updated May 9, 2024

Exercise-induced Erythropoiesis: the Mechanistic of Angiotensin II

A Phase 4 interventional study of Valsartan 80 mg and Placebo in Exercise Physiology, sponsored by The University of Hong Kong. Status unknown at 1 site in Hong Kong. Open to participants aged 20 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-05-09.

Sponsored by The University of Hong Kong · Phase 4, Interventional, and Basic science

The sponsor has not verified this record recently (last verified Dec 2023), so the status shown — last known as Recruiting — may be out of date.
Phase
Phase 4
Study type
Interventional
Enrollment
80
Allocation
Randomized
Ages
20 Years and older
Sex
All
01

Study summary

The major aims are to determine the effect of acute (single dose) blockade of ANGII receptor 1 (AT1) on the EPO response to a single session of endurance exercise, as well as determine the effect of chronic (8-week) blockade of AT1 on ET-induced adaptations in total circulating red blood volume and hemoglobin.

Read the detailed description

Physical activity, particularly when comprised of endurance training (ET) leading to cardiovascular adaptations, is considered the most effective intervention to augment life expectancy. Major health benefits induced by ET are closely associated (independently of traditional risk factors) with improvements in maximal oxygen consumption (VO2max), a hallmark of aerobic exercise capacity. The higher the VO2max the greater the likelihood to be free of cardiovascular disease, the main cause of mortality worldwide. Understanding the mechanisms explaining the improvement in VO2max with ET can provide sound basis for highly effective lifestyle and pharmacological interventions aimed to enhance cardiovascular health in the general population. So far, the essential role of ET-induced increased formation of red blood cells, i.e., erythropoiesis, has been firmly established for any improvement in VO2max. Yet, the underlying mechanism remains elusive. Clinical studies and recent investigations by the PI point towards the endocrine effects of key hormones that regulate blood volume (BV). Notably, the impact of ET-induced changes in angiotensin II (ANGII), a multifaceted hormone that modulates erythropoiesis through its effects on kidney erythropoietin (EPO) production, has to be experimentally elucidated in humans.

02

Conditions studied

  • Exercise Physiology
03

In context

Lead sponsor

The University of Hong Kong is the lead sponsor of 1,286 studies on the registry; 343 are open to participants now.

Of its 9 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.

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

04

Who can participate

Ages eligible
20 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes

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

  • Healthy status, absence of current medical symptoms or medication limiting incremental exercise testing
  • No history of cardiac, pulmonary or kidney disease.

Exclusion criteria

Exclusion Criteria:

- Individuals fulfilling the above criteria but currently involved in regular exercise training (> 5 hr/week)

05

Study design

Phase
Phase 4
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Double (Participant, Investigator)
Enrollment
80 participants (estimated)

Study arms

  • Active comparator
    Valsartan tablets

    Drug: Valsartan 80 mg

  • Placebo comparator
    Placebo tablets

    Drug: Placebo

Interventions

  • The well-established angiotensin II receptor blocker (ARB) valsartan will be used in the present study to selectively block AT1 receptors. Valsartan is a generic medication widely used in hypertensive patients since 1996 as well as safely applied in physiological studies comprising healthy individuals.1-3 A minimal valsartan dose of 80 mg known to acutely reduce circulating EPO levels in healthy individuals will be provided 4 hours before starting Study 1 to optimize AT1 blockade according to valsartan's half-life.1-3 The same dose of valsartan (80 mg) will be provided 4 hours before each ET session in Study 2. The participants will be randomly allocated in a 1:1 ratio to valsartan or placebo. Valsartan and placebo tablets will be indistinguishable in taste, smell, appearance and dosage. The protocol will be developed in a double-blind manner in that both participants and investigators will be blinded toward the intervention condition.

  • DrugPlacebo

    The participants will be randomly allocated in a 1:1 ratio to valsartan or placebo. Valsartan and placebo tablets will be indistinguishable in taste and smell. The protocol will be developed in a double-blind manner in that both participants and investigators will be blinded toward the intervention condition.

06

What researchers measure

Primary outcomes

  1. stroke volume in ml/m2

    Stroke volume (SV) will be determined as left ventricular end-diastolic volume (LVEDV) minus left ventricular end-systolic volume (LVESV)

    Time frame: 10 weeks

  2. maximal oxygen consumption in ml/kg/min

    Maximal oxygen consumption (VO2max), a hallmark of aerobic capacity, will be determined with continuous measurements of oxgyen uptake using an online gas collection system (Quark CPET, Cosmed, Italy)

    Time frame: 10 weeks

  3. Blood volume (BV)-regulating hormone: Plasma ANGII in ng/dL

    Plasma ANGII concentrations will be quantified by means of established competitive enzyme immunoassays

    Time frame: 10 weeks

07

Study locations

1 of 1 sites recruiting
  • School of Public Health
    Hong Kong, Hong Kong
    • David Montero, PhD · Contact · dvmb@hku.hk · 28315250
    Recruiting
08

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Mar 2023 (actual). Primary completion is estimated for Sep 2024, 18 months after the start.

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

Registered
Feb 4, 2022
First posted
Mar 8, 2022
StartActual
Mar 20, 2023
Primary completionEst.
Sep 30, 2024
CompletionEst.
Sep 30, 2024
Last update
May 9, 2024
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.
No changes since tracking began. The registry record was last updated on May 9, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05269615
Responsible party
Sponsor
First posted
Mar 8, 2022
Start date
Mar 20, 2023
Primary completion
Sep 30, 2024 (estimated)
Completion
Sep 30, 2024 (estimated)
Last update
May 9, 2024

Study contacts

David Montero Barril, PhD
Contact
dvmb@hku.hk
66924724

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 status unknown, as verified in Dec 2023. You cannot join it, but the record below documents what was studied.

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Studies of the drug tested here: Valsartan

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