A First-In-Human Study of ARO-INHBE in Adults With Obesity With and Without Type 2 Diabetes Mellitus

What Was Tested

The trial (phase 1, phase 2) is built around Tirzepatide.

It had eight arms (groups): Part 1: ARO-INHBE (experimental), Part 1: Placebo (placebo comparator), Part 2: ARO-INHBE + Tirzepatide (experimental), Part 2: Placebo + Tirzepatide (placebo comparator) and Part 3: ARO-INHBE (experimental).

The registry classes the interventions as drug.

Who Took Part

Enrollment: 180 planned participants were the target.

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

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Obesity, defined as Body Mass Index (BMI) between 30 to 50 kilograms (kg)/square meter (m\^2) at Screening. At least one self-reported, unsuccessful attempt at weight loss with lifestyle modification. No abnormal finding of clinical relevance at Screening that, in the opinion of investigator, could adversely impact participant safety or adversely impact study results.

The full record lists 6 inclusion and 9 exclusion criteria; among the exclusions: use of glucagon-like protein 1 receptor (glp1r) agonists (liraglutide, semaglutide, etc.) for any indication within 6 months prior to screening; obesity attributable, in the investigator's opinion, to medication use, monogenic, or endocrinologic disorders (other than polycystic ovary syndrome); history or prior surgical or device-based therapy for obesity.

How the Study Was Run

Design: randomized, parallel-group and quadruple-blind.

Random assignment meant chance, not the researchers, decided who got Tirzepatide and who got the comparison, which limits bias.

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 2024-12-04 with completion listed for 2027-09-17.

It ran at 15 sites in Australia (4), Georgia (4), New Zealand (4) and Canada (3).

Its stated primary purpose is treatment.

What Was Measured

Researchers chose this as the main measure: Number of Participants with Treatment-Emergent Adverse Events (TEAEs) (time frame: Up to Day 365).

It also tracked 11 secondary outcomes, for example PK of ARO-INHBE: Maximum observed Plasma Concentration (Cmax), PK of ARO-INHBE: Time to Maximum Observed Plasma Concentration (Tmax), PK of ARO-INHBE: Area Under the Plasma Concentration Versus Time Curve from Zero to 24 Hours (AUC0-24), PK of ARO-INHBE: Area Under the Plasma Concentration Versus Time Curve from Zero to the Last Quantifiable Plasma Concentration (AUC0-t), PK of ARO-INHBE: Area Under the Plasma Concentration Versus Time Curve from Zero to Infinity (AUC0-∞) and PK of ARO-INHBE: Terminal Half-life (t1/2).

What This Means in Plain Language

Put simply, this is a phase 1, phase 2, randomized trial of Tirzepatide in 180 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.