A Study to Evaluate Different Oral Formulations of KT-621

A Phase 1, Open-Label, Crossover Study to Evaluate the Relative Bioavailability of Different Oral Formulations of KT-621 in Healthy Adult Participants

This is a Phase I study to evaluate the relative bioavailability and safety and tolerability of different oral formulations of KT-621 in healthy adult participants.

Study Overview

• Status: Recruiting
• Conditions: Healthy Participants
• Intervention / Treatment: Drug: KT-621; Drug: KT-621; Drug: KT-621

• Study Type: Interventional
• Enrollment (Estimated): 54
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Kymera Medical Director; Phone Number: 857-285-5300; Email: clinicaltrials@kymeratx.com

Study Locations

• United States
  • Nebraska
    • Lincoln, Nebraska, United States, 68502
      • Recruiting
      • Celerion

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Participants with a weight of at least 50 kilograms (kg) if male or 40 kg if female, and a body mass index (BMI) between 18.0 and 32.0 kg/m² (inclusive) at Screening.
• Participants must be willing and able to read, understand, and sign an informed consent form (ICF) which includes compliance with requirements and restrictions listed in the ICF and in this protocol.
• Participants must be willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures.

Exclusion Criteria:

• Participants who have a clinically relevant history of respiratory, gastrointestinal (GI), renal, hepatic, hematological, lymphatic, endocrinological, neurological, cardiovascular, psychiatric, musculoskeletal, genitourinary, immunological, dermatological, ophthalmological, or connective tissue diseases or disorders.
• Participants who have a clinically relevant surgical history (for example, surgery of the GI tract that could interfere with the PK of the study medication). Note: prior appendectomy or cholecystectomy is not exclusionary.
• Participants who have any known factor, condition, or disease that might interfere with treatment compliance, study conduct or interpretation of the results such as drug or alcohol dependence or psychiatric disease.
• Participants who have acute GI symptoms at the time of Screening or admission to the CRU (for example, nausea, vomiting, diarrhea, heartburn).
• Participants whose results from clinical laboratory safety tests are outside the local reference range at Screening or on admission to the CRU.
• Participants who have been dosed with any investigational drug or device in a clinical study within 30 days or 5 half-lives, or time determined by local requirements (whichever is longer) prior to admission to the CRU.
• Male participants who do not agree to refrain from sperm donation from admission to the CRU to 90 days after the last dose of KT-621.
• Male participants (and their partners of childbearing potential) and female participants who do not agree to the contraception requirements as specified in the clinical protocol.
• Female participants who are pregnant, lactating, or breastfeeding, or plan to become pregnant during study participation or within 30 days of the last dose of KT-621.
• Female participants with a positive or undetermined pregnancy result at the Screening visit or at admission to the CRU.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Non-Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A: KT-621 Test Formulation #1; Participants will receive KT-621 in different oral formulations in a one-way crossover design.	Drug: KT-621; KT-621 Reference Oral Formulation; Drug: KT-621; KT-621 Test Oral Formulation #1; Drug: KT-621; KT-621 Test Oral Formulation #2
Experimental: Part B: KT-621 Test Formulation #2; Participants will receive KT-621 in different oral formulations in a one-way crossover design.	Drug: KT-621; KT-621 Reference Oral Formulation; Drug: KT-621; KT-621 Test Oral Formulation #1; Drug: KT-621; KT-621 Test Oral Formulation #2

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Maximum Plasma Concentration (Cmax) of KT-621	Day 1 through Day 24 (Part A); Day 1 through Day 30 (Part B)
Area Under the Plasma Concentration-Time Curve From Time Zero to the Time of the Last Quantifiable Concentration (AUClast) of KT-621	Day 1 through Day 24 (Part A); Day 1 through Day 30 (Part B)
Area Under the Plasma Concentration-Time Curve From Time Zero Extrapolated to Infinity (AUC∞) of KT-621	Day 1 through Day 24 (Part A); Day 1 through Day 30 (Part B)

Secondary Outcome Measures

Outcome Measure	Time Frame
Incidence of adverse events	From signing of the ICF through the safety follow-up on Day 33 (Part A) or Day 39 (Part B)
Incidence of serious adverse events	From signing of the ICF through the safety follow-up visit on Day 33 (Part A) or Day 39 (Part B)

Collaborators and Investigators

• Sponsor: Kymera Therapeutics, Inc.

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): May 1, 2027

Study Registration Dates

• First Submitted: September 11, 2026
• First Submitted That Met QC Criteria: September 11, 2026
• First Posted (Actual): September 16, 2026

Study Record Updates

• Last Update Posted (Actual): September 16, 2026
• Last Update Submitted That Met QC Criteria: September 11, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: STAT6; STAT6 degrader; targeted protein degrader
• Other Study ID Numbers: KT621-HV-105

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