Phase 1/2a Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics and Effect on Body Weight of RN3161 as Monotherapy and in Combination With Tirzepatide in Adults With Overweight and Obesity

What Was Tested

In this phase 1, phase 2 trial, researchers set out to test Tirzepatide.

It had four arms (groups): RN3161 (experimental), Placebo Control (placebo comparator), RN3161 and tirzepatide (experimental) and Placebo and tirzepatide (active comparator).

Investigational Product.

Placebo control.

In Part 3, RN3161 co-administered with tirezepatide.

The registry classes the interventions as drug.

Who Took Part

104 planned participants were the target.

It was open to people of any sex aged from 18 years up to 65 years.

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

The full record lists 4 inclusion and 8 exclusion criteria; among the exclusions: use of glp1r agonists within 6 months of screening; intolerance to glp-1 medications in the past; use of non-glp1r medications for weight loss within 3 months of screening.

How the Study Was Run

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

Because people in this Tirzepatide study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

The Tirzepatide group and the comparison group ran side by side rather than switching.

As a double-blind Tirzepatide study, the assignments were hidden from both participants and investigators until the end.

Those kept unaware of assignments: participant, care provider, investigator and outcomes assessor.

It started in 2025-11-04 with completion listed for 2027-02-15.

It ran at 1 site in Australia.

Its stated primary purpose is treatment.

What Was Measured

Researchers chose this as the main measure: Blood Pressure (time frame: 180 Days). ECG PR interval (time frame: 180 days). Physical Examination (time frame: 180 days).

It also tracked 2 secondary outcomes, for example Presence of ADA.

What This Means in Plain Language

Put simply, this is a phase 1, phase 2, randomized trial of Tirzepatide in 104 people.

It is still recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

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