A Study of LY4167586 in Participants With Obesity or Overweight Who Are Otherwise Healthy

A Phase 1, Randomized, Placebo-Controlled, Single Ascending Dose-Escalation Study to Investigate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of LY4167586 in Participants With Obesity or Overweight Who Are Otherwise Healthy

The purpose of this study is to look at how safe and well-tolerated LY4167586 is in participants with obesity or overweight who are otherwise healthy. Blood tests will be performed to check how much LY4167586 gets into the bloodstream and how long it takes the body to eliminate it following a single administration. Participation in the study will last approximately 7 months.

Study Overview

• Status: Recruiting
• Conditions: Obesity; Overweight
• Intervention / Treatment: Drug: Placebo; Drug: LY4167586; Drug: LY4167586

• Study Type: Interventional
• Enrollment (Estimated): 84
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Trial questions or participation questions: 1-877-CTLILLY (1-877-285-4559) or; Phone Number: 1-317-615-4559; Email: LillyTrials@Lilly.com
• Study Contact Backup: Name: Physicians interested in becoming principal investigators please contact; Email: clinical_inquiry_hub@lilly.com

Study Locations

• Singapore
  • Singapore, Singapore, 138623
    • Recruiting
    • Lilly Centre for Clinical Pharmacology
    • Principal Investigator: Jennifer Boon Wee
    • Contact: Phone Number: +65 6413 9811
• United States
  • Wisconsin
    • Madison, Wisconsin, United States, 53704
      • Recruiting
      • Fortrea Clinical Research Unit
      • Principal Investigator: Kimberly Cruz
      • Contact: Phone Number: 866-429-3700

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Participant must be 21 for Singapore site
• Have a body mass index (BMI) between 27.0 kilogram per square meter (kg/m²) and 35.0 kg/m², inclusive
• Have had a self-reported stable weight for 3 months prior to screening (less than approximately 5 percent [%] body weight change)

Exclusion Criteria:

• Have a history or presence of cardiovascular, respiratory, hepatic, renal, gastrointestinal (GI), endocrine, hematological, or neurological disorders capable of significantly altering the absorption, metabolism, or elimination of drugs, or of constituting a risk when taking the study drug, or of interfering with the interpretation of data.
• Is an individual of childbearing potential (IOCBP)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: LY4167586 (Cohorts A1 to A6); LY4167586 administered subcutaneously (SC)	Drug: LY4167586; Administered SC; Drug: LY4167586; Administered IV
Placebo Comparator: LY4167586 (Cohorts A1 to A6) Placebo; LY4167586 administered SC	Drug: Placebo; Administered SC
Experimental: LY4167586 (Cohort B); LY4167586 administered intravenously (IV)	Drug: LY4167586; Administered SC; Drug: LY4167586; Administered IV

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number and Incidence of Serious Adverse Events (SAEs)	A summary of SAEs regardless of causality, will be reported in the Reported Adverse Events module	Baseline to study completion (up to 29 weeks)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pharmacokinetics (PK): Maximum Observed Drug Concentration (Cmax)	PK: Cmax of LY4167586	Predose on Day 1 through end of the Follow-up Period (Week 25)
PK: Time of Maximum Drug Concentration (tmax)	PK: tmax of LY4167586	Predose on Day 1 through end of the Follow-up Period (Week 25)
PK: Area Under the Concentration Versus Time Curve (AUC)	PK: AUC of LY4167586	Predose on Day 1 through end of the Follow-up Period (Week 25)

Collaborators and Investigators

• Sponsor: Eli Lilly and Company
• Investigators: Study Director: Call 1-877-CTLILLY (1-877-285-4559) or 1-317-615-4559 Mon - Fri 8 AM - 8 PM Eastern time (UTC/GMT - 5 hours, EST), Eli Lilly and Company

Study record dates

Study Major Dates

• Study Start (Actual): November 18, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: October 20, 2025
• First Submitted That Met QC Criteria: November 5, 2025
• First Posted (Actual): November 6, 2025

Study Record Updates

• Last Update Posted (Actual): March 9, 2026
• Last Update Submitted That Met QC Criteria: March 6, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity
• Other Study ID Numbers: 27659 (SLU IRB); J6L-MC-YIAA (Other Identifier: Eli Lilly and Company)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No