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

NCT04991766 | Completed Phase 1 Results FDA Drug

• 2 other identifiers: 18205J2J-MC-JZLE
• Study Type: interventional
• Target: 16
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Healthy

Keywords

Metabolism; Absolute Bioavailability; Disposition

Outcome Measures

Primary Outcomes (3)

• 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 Outcomes (11)

• Part 1: PK: Total Radioactivity Recovered in Urine, Feces

  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

  predose, 8, and 24 hours postdose

• Part 1: PK: Total Number of Metabolites of LY3484356 in Plasma, Urine and Feces

  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

  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

  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

Study Arms (2)

[¹⁴C]-LY3484356 (Part 1)

EXPERIMENTAL

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

LY3484356 + [¹⁴C]-LY3484356 (Part 2)

EXPERIMENTAL

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; Drug: [¹⁴C]-LY3484356 (IV)

Interventions

[¹⁴C]-LY3484356 DRUG

Administered orally.

[¹⁴C]-LY3484356 (Part 1)

LY3484356 DRUG

Administered orally.

LY3484356 + [¹⁴C]-LY3484356 (Part 2)

[¹⁴C]-LY3484356 (IV) DRUG

Administered IV.

LY3484356 + [¹⁴C]-LY3484356 (Part 2)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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)

You may not qualify if:

• 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

Sponsors & Collaborators

• Eli Lilly and Company: lead

Study Sites (1)

LabCorp CRU, Inc.

Madison, Wisconsin, 53704, United States

Location

MeSH Terms

Interventions

Imlunestrant

Results Point of Contact

• Title: Chief Medical Officer
• Organization: Eli Lilly and Company

ClinicalTrials.gov@lilly.com

800-545-5979

Study Officials

• 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 DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: GT60
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 2, 2021
• First Posted: August 5, 2021
• Study Start: August 13, 2021
• Primary Completion: April 2, 2022
• Study Completion: April 2, 2022
• Last Updated: December 5, 2025
• Results First Posted: December 5, 2025

Record last verified: 2025-11-15

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)