Effects of Apelin on the Lung Circulation in Pulmonary Hypertension

What Was Tested

In this not phased trial, researchers set out to test Apelin.

The purpose of this study is to determine the effects of Apelin on the lung circulation.

It had two arms (groups): Apelin/Saline (experimental) and Saline/Apelin (experimental).

Apelin infusion then crossover to Saline infusion.

Saline infusion then crossover to Apelin infusion.

The registry classes the interventions as drug.

More on the Plan

Apelin is an endogenous peptide with physiological actions in the cardiovascular system and is abundantly expressed in the pulmonary vasculature.

Pre-clinical models and preliminary clinical data indicate that Apelin deficiency may mediate or contribute to the pathogenesis of pulmonary hypertension and heart failure.

The investigators will determine the effects of Apelin on the pulmonary circulation in 3 groups; healthy control, people with pulmonary arterial hypertension and people with pulmonary hypertension due to heart failure.

Each subject will receive both Apelin infusion and saline placebo infusion in a crossover design.

Who Took Part

The registry lists 63 planned participants were the target.

It was open to people of any sex aged from 18 years with no upper age limit.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Mean pulmonary artery pressure \>/= 25mmHg. Pulmonary capillary wedge pressure \< 15 mmHg. WHO functional class II - IV.

The full record lists 6 inclusion and 20 exclusion criteria; among the exclusions: chronic thromboembolic pulmonary hypertension; stable on treatment for 3 months prior to study; NYHA grade II - IV.

How the Study Was Run

Design: randomized, crossover and double-blind.

The participants were allocated by chance, so the Apelin group and the comparison group should start out alike.

In the crossover set-up each of the participants took both Apelin and the comparison in turn, acting as their own control.

Neither the participants nor the staff measuring them knew who was on Apelin, so expectations could not easily colour the readings.

Those kept unaware of assignments: participant and investigator.

It started in 2012-01 with completion listed for 2014-01.

It ran at 3 sites in United Kingdom (3).

Its stated primary purpose is basic science.

What Was Measured

Researchers chose this as the main measure: Change in pulmonary vascular resistance (time frame: 5,10,15 and 30 minutes after start of infusion).

It also tracked 2 secondary outcomes, for example Change in systemic vascular resistance and Change in Cardiac Output.

What This Means in Plain Language

Put simply, this is a not phased, randomized trial of Apelin in 63 people.

Its status is unknown; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Apelin compound page, all human trials.