A Study of [¹⁴C]-LY3484356 in Healthy Female Participants

An Open-label, Two-part Study of the Disposition and Absolute Bioavailability of [¹⁴C]-LY3484356 in Healthy Females of Non-Childbearing Potential

The main purpose of this study is to measure how much of the study drug gets into the bloodstream and how long it takes the body to get rid of it. This study has two parts. It will involve a single dose of 14C radiolabeled LY3484356. This means that a radioactive substance C14 will be incorporated into the study drug, to investigate the study drug and its breakdown products, to find out how much of these pass from blood into urine, feces and expired air. The study will last about 4 weeks. Screening is required within 28 days prior to the start of the study and follow up is required approximately 7 days after discharge.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Drug: LY3484356; Drug: [¹⁴C]-LY3484356; Drug: [¹⁴C]-LY3484356 (IV)

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Wisconsin
    • Madison, Wisconsin, United States, 53704
      • LabCorp CRU, Inc.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Female participants of nonchildbearing potential. This includes females who are not pregnant, non-lactating and either: Infertile due to surgical sterilization or alternate medical cause/congenital or postmenopausal.
• Body mass index (BMI) within the range of 18.0 to 35.0 kilograms per meter squared (kg/m²)

Exclusion Criteria:

• Significant history or clinical manifestation of any metabolic, allergic, dermatological, hepatic, renal, hematological, pulmonary, cardiovascular, gastrointestinal, neurological, respiratory, endocrine, or psychiatric disorders
• Have evidence of human immunodeficiency virus (HIV) infection and/or positive human HIV antibodies
• Have known allergies to LY3484356, related compounds or any components of the formulation as appropriate, or history of significant atopy

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: [¹⁴C]-LY3484356 (Part 1); Participants received a single oral dose of 400 mg Carbon 14 labelled [¹⁴C]-LY3484356 following an overnight fast of at least 10 hours on Day 1.	Drug: [¹⁴C]-LY3484356; Administered orally.
Experimental: LY3484356 + [¹⁴C]-LY3484356 (Part 2); Participants received a single oral dose of 400 mg LY3484356 following an overnight fast of at least 10 hours on Day 1, followed 4 hours later by a single dose of less than 100 microgram (μg) [¹⁴C]-LY3484356 (actual ranged from 44.55 to 45.95 μg), as an intravenous (IV) infusion on day 1.	Drug: LY3484356; Administered orally.; Drug: [¹⁴C]-LY3484356 (IV); Administered IV.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: Pharmacokinetics (PK): Fecal Excretion of LY3484356 Radioactivity Over Time Expressed as a Percentage of the Total Radioactive Dose Administered	The percentage of the total radioactive dose administered that was excreted in feces = (amount of radioactive dose recovered in feces / total radioactive dose administered) * 100.	Predose, 24, 48, 72, 96, 120, 144, 168,192, 216, 240, 264, 288 and 312 hours post dose
Part 1: PK: Urinary Excretion of LY3484356 Radioactivity Over Time Expressed as a Percentage of the Total Radioactive Dose Administered	The percentage of the total radioactive dose administered that was excreted in urine = (amount of radioactive dose recovered in urine / total radioactive dose administered) * 100.	Predose, 24, 48 ,72, 96, 120, 144, 168, 192, 216, 240, 264, 288 and 312 hours post dose
Part 2: Pharmacokinetics (PK): Percent Absolute Bioavailability (F%) of LY3484356	PK: Bioavailability is defined as the percentage of a drug which enters the circulation when introduced into the body and so is able to have an active effect. Percent absolute bioavailability, calculated for plasma LY3484356 as "F %= [AUC (0-∞), LY3484356] × [Dose, [14C]-LY3484356] / [AUC (0-∞), [14C]-LY3484356] × [Dose, LY3484356] ×100%'' Higher percent indicates better absorption of drug into the body.	Predose, 5 minutes(min), 15 min, 20 min, 30 min, 45 min, and 1, 2, 3, 4, 6, 8, 10, 12, 24, 48, 72, 96, 120, 144, 168, and 192 hours postdose

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: PK: Total Radioactivity Recovered in Urine, Feces	Relative abundance was expressed and calculated as the percentage of administered dose excreted in urine/Feces=[(percentage of radioactivity in peak)/100]*(percentage of dose in sample).	Predose, 24, 48, 96, 120, 144, 168, 192, 216, 240, 264, 288, 312, 336, 360, 384, 408, 432, 456 and 480 hours post dose
Part 1: Total Radioactivity Recovered in Expired Air	Radioactivity is expressed in becquerels (Bq), the International System of Unit (SI) representing one nuclear disintegration per second. For practical measurement, total radioactivity recovered in expired air is reported in disintegrations per minute (dpm). The conversion factor is: 1 Bq = 60 dpm.	predose, 8, and 24 hours postdose
Part 1: PK: Total Number of Metabolites of LY3484356 in Plasma, Urine and Feces	Total number of metabolites of LY3484356 is reported. The value is an absolute number without any measure of central tendency.	Plasma:Predose,24,48,72,96,120,144,168,192,216,240,264 and 288 hours(h) post dose;Urine:-12 to 0h Predose,0 to 6,6-12,and 12-24,48,72,96,120,144,168,192,216,240 and 264 hours post dose;Feces:Predose,24,48,72,96,120,144, 168,192,216,240 and 264 h post dose
Part 1: PK: Area Under the Concentration-Time Curve From Time Zero to Infinity (AUC [0-∞]) for LY3484356 in Plasma	PK: AUC [0-∞] of LY3484356 in Plasma.	Part 1: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8,10, 12, 24, 48, 72, 96,120, 144, 168, 192, 216, 240, and 264 hours post-dose
Part 1: PK: Area Under the Concentration-Time Curve From Time Zero to Infinity (AUC [0-∞]) for Total Radioactivity in Plasma	PK: AUC [0-∞] of Plasma Total Radioactivity. Total radioactivity is reported as nanogram* hours equivalents per milliliter (ng*h Eq/mL).	Part 1: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8,10, 12, 24, 48, 72, 96,120, 144, 168, 192, 216, 240, and 264 hours post-dose
Part 1: PK: Maximum Concentration (Cmax) for LY3484356 in Plasma	PK: Cmax for LY3484356 in plasma.	Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8,10, 12, 24, 48, 72, 96,120, 144, 168, 192, 216, 240, and 264 hours post-dose
Part 1: PK: Maximum Concentration (Cmax) for Total Radioactivity in Plasma	PK: Cmax for total radioactivity in plasma. The Cmax of total radioactivity are reported as nanogram equivalents per milliliter (ng Eq/mL).	Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8,10, 12, 24, 48, 72, 96,120, 144, 168, 192, 216, 240, and 264 hours post-dose
Part 2: PK: Area Under the Concentration-Time Curve From Time Zero to Infinity (AUC [0-∞]) for [¹⁴C]-LY3484356 and LY3484356 in Plasma	PK: AUC [0-∞] of Total Radioactivity. Total radioactivity is reported as hours*nanogram equivalents per milliliter (h*ng Eq/mL).	Predose, 5 minutes(min), 15 min, 20 min, 30 min, 45 min, and 1, 2, 3, 4, 6, 8, 10, 12, 24, 48, 72, 96, 120, 144, 168, and 192 hours postdose
Part 2: PK: Area Under the Concentration-Time Curve From Time Zero to Infinity (AUC [0-∞]) for Total Radioactivity in Plasma	PK: AUC [0-∞] of Total Radioactivity in Plasma.	Predose, 5 minutes(min), 15 min, 20 min, 30 min, 45 min, and 1, 2, 3, 4, 6, 8, 10, 12, 24, 48, 72, 96, 120, 144, 168, and 192 hours postdose
Part 2: PK: Maximum Concentration (Cmax) for [¹⁴C]-LY3484356 and LY3484356 in Plasma	PK: Cmax of LY3484356 and [¹⁴C]-LY3484356 in plasma.	Predose, 5 minutes(min), 15 min, 20 min, 30 min, 45 min, and 1, 2, 3, 4, 6, 8, 10, 12, 24, 48, 72, 96, 120, 144, 168, and 192 hours postdose
Part 2: PK: Maximum Concentration (Cmax) for Total Radioactivity in Plasma	PK: Cmax of total radioactivity in plasma.	Predose, 5 minutes(min), 15 min, 20 min, 30 min, 45 min, and 1, 2, 3, 4, 6, 8, 10, 12, 24, 48, 72, 96, 120, 144, 168, and 192 hours postdose

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 9 AM - 5 PM Eastern time (UTC/GMT - 5 hours, EST), Eli Lilly and Company

Study record dates

Study Major Dates

• Study Start (Actual): August 13, 2021
• Primary Completion (Actual): April 2, 2022
• Study Completion (Actual): April 2, 2022

Study Registration Dates

• First Submitted: August 2, 2021
• First Submitted That Met QC Criteria: August 2, 2021
• First Posted (Actual): August 5, 2021

Study Record Updates

• Last Update Posted (Actual): December 5, 2025
• Last Update Submitted That Met QC Criteria: November 20, 2025
• Last Verified: November 15, 2025

More Information

Terms related to this study

• Keywords: Metabolism; Absolute Bioavailability; Disposition
• Additional Relevant MeSH Terms: Imlunestrant
• Other Study ID Numbers: 18205; J2J-MC-JZLE (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