A Series of Pilot Studies to Evaluate the haemoDynamic and mEtabolic Effects oF apelIn aNd rElaxin

What Was Tested

This registered phase 2 trial tested Apelin and Relaxin (Serelaxin).

Type two diabetes mellitus (T2DM) is a common, long term metabolic disorder characterised by hyperglycaemia (high blood glucose) resulting from insulin resistance and relative insulin insufficiency.

As the onset can be gradual, physiological damage may have occurred prior to diagnosis.

It had eight arms (groups): Substudy 1A - Apelin (experimental), Substudy 1B - Apelin/Normal Saline (experimental), Substudy 2A - Relaxin/Normal Saline (experimental), Substudy 2B - Relaxin (experimental) and Substudy 3A - Relaxin with Apelin/Saline (experimental).

In sub-study 2A Healthy participants will receive intra-arterial infusions of Relaxin.

The registry classes the interventions as diagnostic test and drug.

More on the Plan

While the precise cellular mechanisms involved remain to be elucidated, the researchers hypothesise that the apelin and relaxin pathways meet these two criteria and therefore are potential therapeutic targets in conditions of abnormal glucose metabolism and heart failure.

Who Took Part

The registry lists 170 planned participants were the target.

It was open to people of any sex aged from 18 years up to 75 years.

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

Examples of who could join: Have given written informed consent to participate. Aged 18 to 70 years inclusive. Male or female. If female, either postmenopausal or on days 2-9 of menstrual cycle and negative pregnancy test performed on the day of the of visit. BMI in range for studies 2 and 3: 18.5-30.0 kg/m2 without limitations in waist circumference or body fat level.

The full record lists 20 inclusion and 20 exclusion criteria; among the exclusions: hypersensitivity to any of the study drugs or excipients; systemic hypertension (sustained bp \>160/100mmhg) or hypotension (systolic bp below 90 mmhg); known heart disease.

How the Study Was Run

It was run as a randomized, parallel-group and triple-blind study.

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

Groups ran in parallel: each of the participants stayed in one arm throughout.

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, investigator and outcomes assessor.

It started in 2018-03-28 with completion listed for 2026-12.

It ran at 1 site in United Kingdom.

Its stated primary purpose is other.

What Was Measured

The main thing measured (primary outcome): Sub-study 1a: Changes in markers of glucose homeostasis in healthy participants after infusion of apelin (Glucose) (time frame: Visit 2 to visit 4, over a period of up to 8 weeks). Sub-study 1a: Changes in markers of glucose homeostasis in healthy participants after infusion of apelin (C-Peptide) (time frame: Visit 2 to visit 4, over a period of up to 8 weeks). Sub-study 1a: Changes in markers of glucose homeostasis in healthy participants after infusion of apelin (Glucagon) (time frame: Visit 2 to visit 4, over a period of up to 8 weeks).

It also tracked 28 secondary outcomes, for example Sub-study 1a: Changes in parameters of cardiovascular haemodynamics in healthy participants after infusion of apelin (Echocardiography), Sub-study 1a: Changes in parameters of cardiovascular haemodynamics in healthy participants after infusion of apelin (Innocor), Sub-study 1a: Changes in parameters of cardiovascular haemodynamics in healthy participants after infusion of apelin (Bioimpedance), Sub-study 2b: Change in forearm blood flow parameters after infusion of verapamil in the presence of L-NMMA or saline (Ratio), Sub-study 2b: Change in forearm blood flow parameters after infusion of verapamil in the presence of L-NMMA or saline (Absolute Flow) and Sub-study 2b: Change in forearm blood flow parameters after infusion of verapamil in the presence of L-NMMA or saline (Percentage Change).

What This Means in Plain Language

Put simply, this is a phase 2, randomized trial of Apelin and Relaxin (Serelaxin) in 170 people.

Its status is active not recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Apelin compound page and the Relaxin (Serelaxin) compound page, all human trials.