A Study of LY4064809 in Healthy Adult Participants

A Phase 1, Open-Label Study to Assess the Relative Bioavailability of Two LY4064809 Formulations in Healthy Adult Participants

The purpose of this study is to find out how much LY4064809 gets into the blood stream and how long it takes the body to get rid of it when it is given as two formulations. For each participant, the study will last about nine weeks. Participants will remain in the clinical research center for about one month.

Study Overview

• Status: Completed
• Conditions: Healthy Participants
• Intervention / Treatment: Drug: LY4064809 Test Formulation; Drug: LY4064809 Reference Formulation

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Wisconsin
    • Madison, Wisconsin, United States, 53704-2526
      • Fortrea Clinical Research Unit Inc. - Madison

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Are healthy as determined by medical evaluation, including medical history, physical examination, vital signs, and electrocardiogram (ECG) at screening and admission.
• Have clinical laboratory test results within the normal range
• Have normal blood pressure and pulse rate or not clinically significant
• Have a BMI within the range 18 to 32 kg/m2
• Participants assigned male at birth or assigned female at birth who are not of childbearing potential

Exclusion Criteria:

• History or presence of any of the following conditions, deemed clinically significant by the investigator (or designee):

  • metabolic disease, including congenital non-hemolytic hyperbilirubinemia, for example, Gilbert syndrome
  • bile duct disease, including removal of the gall bladder
  • digestive system disease
  • blood disease
  • disease of the nervous system
  • significant history of, or presence of, liver disease, including any abnormal liver function tests
  • heart disease
• Have an abnormal electrocardiogram (ECG) at screening or admission
• History of a major surgical procedure within 30 days prior to screening

• Diagnosed or treated cancer within 5 years prior to screening, with the exception of the following cancers cured through treatment: basal cell carcinoma of the skin, squamous cell carcinoma of the skin, and in situ carcinoma of the cervix cured through surgery

  • Clinically significant history of multiple or severe drug hypersensitivity reactions or drug allergies, as determined by the investigator
• Have used or plan to use medication within 14 days prior to admission, or plan to use during the study with the exception of acetaminophen
• Have creatinine lab clearance less than 90mL/min calculated using the Cockroft-Gault equation at screening
• Have a positive Hepatitis B surface antigen (HBsAg), hepatitis C virus antibody or human immunodeficiency virus 1 and 2 antibody results at the screening visit

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: LY4064809 Test; LY4064809 test (Phase 3 formulation) formulation administered orally in one of two periods.	Drug: LY4064809 Test Formulation; Administered orally; Other Names: STX-478; Drug: LY4064809 Reference Formulation; Administered orally; Other Names: STX-478
Experimental: LY4064809 Reference; LY4064809 reference (Phase 1 formulation) formulation administered orally in one of two periods.	Drug: LY4064809 Test Formulation; Administered orally; Other Names: STX-478; Drug: LY4064809 Reference Formulation; Administered orally; Other Names: STX-478

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pharmacokinetics (PK): Maximum Concentration (Cmax) of LY4064809	PK: Cmax of LY4064809	Predose on Day 1 Through Day 28
PK: Area Under the Concentration Versus Time Curve (AUC) of LY4064809	PK: AUC of LY4064809	Predose on Day 1 Through Day 28

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): January 12, 2026
• Primary Completion (Actual): March 19, 2026
• Study Completion (Actual): March 19, 2026

Study Registration Dates

• First Submitted: January 6, 2026
• First Submitted That Met QC Criteria: January 6, 2026
• First Posted (Actual): January 14, 2026

Study Record Updates

• Last Update Posted (Actual): April 20, 2026
• Last Update Submitted That Met QC Criteria: April 17, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: STX-478
• Other Study ID Numbers: 27796; J6M-MC-JSGG (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