Recruiting

Phase 1

KQB365 & CetuximabA Study to Investigate the Safety and Efficacy of KQB365 as Monotherapy and in Combination in Participants With Advanced Solid Malignancies

Sponsor:

Kumquat Biosciences Inc.

Code:

NCT06720987

Conditions

KRAS G12C Mutation

KRAS G12S Mutation

Solid Tumor Malignancies

CRC (Colorectal Cancer)

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

KQB365

Cetuximab

KQB198

Study Details

Brief summary:

The goal of this clinical trial is to learn if KQB365 works to treat advanced solid tumor cancer in adults. It will also learn about the safety of KQB365. The main questions it aims to answer are:

What is the safe dose of KQB365 by itself, in combination with cetuximab, or in combination with KQB198?
Does KQB365 alone, in combination with cetuximab, or in combination with KQB198 decrease the size of the tumor?
What happens to KQB365 in the body?

Participants will:

Receive KQB365 infusion weekly alone, in combination with cetuximab, or in combination with oral KQB198.
Visit the clinic about 9 times in the first 6 weeks, and then once every week after that.

Conditions

KRAS G12C Mutation

KRAS G12S Mutation

Solid Tumor Malignancies

CRC (Colorectal Cancer)

Study ID

NCT06720987

Start date

Feb 4, 2025

Status verified date

Apr, 2026

Completion date

Jun 30, 2030

Anticipated

Primary completion date

Jun 30, 2029

Anticipated

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

PART 1 (monotherapy and combo therapy with KQB198): Histologically confirmed diagnosis of a solid tumor malignancy with either a KRAS G12C or KRAS G12S mutation.
PART 1 (combo therapy with Cetuximab) \& PART 2: Histologically confirmed diagnosis of adenocarcinoma of the colon or rectum with either a KRAS G12C or KRAS G12S mutation.
Unresectable or metastatic disease
No available treatment with curative intent
Adequate organ function
Measurable disease per RECIST v1.1

Exclusion Criteria:

Active primary central nervous system tumors
Cardiac abnormalities
Active interstitial lung disease
Unable to swallow or GI condition that prevents absorption for patients in KQB198 combination cohorts

Study Design

Enrollment

140 participants

Anticipated

Allocation

Non randomized

Intervention Model

Sequential

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Monotherapy Dose Escalation (Part 1)

Drug: KQB365

\- Intravenous KQB365

experimental: Combo Therapy with Cetuximab Dose Escalation (Part 1)

Drug: KQB365 - Intravenous KQB365

Drug:

\- Intravenous cetuximab

experimental: Monotherapy Dose Expansion - RP2D (Part 2)

Drug: KQB365

\- Intravenous KQB365

experimental: Monotherapy Dose Expansion - RP2D-1 (Part 2)

Drug: KQB365

\- Intravenous KQB365

experimental: Combo Therapy with Cetuximab Dose Expansion - RP2D (Part 2)

Drug: KQB365 - Intravenous KQB365

Drug:

\- Intravenous cetuximab

experimental: Combo Therapy with Cetuximab Dose Expansion - RP2D-1 (Part 2)

Drug: KQB365 - Intravenous KQB365

Drug:

\- Intravenous cetuximab

experimental: Combo Therapy with KQB198 Dose Escalation (Part 1)

Drug: KQB365 - Intravenous KQB365

Drug:

\- Oral KQB198

Interventions

KQB365

Intravenous KQB365

Cetuximab

Intravenous cetuximab

KQB198

Oral KQB198

Primary outcome measure

Number of patients who experience treatment-emergent adverse events, serious adverse events, and dose-limiting toxicities (Part 1) [ Time Frame: From enrollment to the end of treatment ]
Recommended Phase 2 Dose (RP2D) (Part 1) [ Time Frame: up to 35 months ]
Efficacy and Optimal Biologic Dose of study treatment, as measured by Objective Response Rate (ORR) (Part 2) [ Time Frame: up to 35 months ]

Central Contacts and Locations

Central contacts

Kumquat Clinical Development

(858) 214-2700 kumquatstudies@kumquatbio.com

Locations

Mayo Clinic, Phoenix

Recruiting

Phoenix, Arizona, United States, 85054

Contacts

855-776-0015

Sarah Cannon Cancer Institute at HealthONE

Recruiting

Denver, Colorado, United States, 80218

Contacts

720-754-2610 cann.ddudenvergeneral@sarahcannon.com

Mayo Clinic, Jacksonville

Recruiting

Jacksonville, Florida, United States, 32224

Contacts

855-776-0015

Dana Farber Cancer Institute

Recruiting

Boston, Massachusetts, United States, 02215

Contacts

Danielle Lindquist

857-215-2351 daniellea_lindquist@dfci.harvard.edu

START Midwest

Recruiting

Grand Rapids, Michigan, United States, 49546

Contacts

Ashley Spagnuolo

616-954-5552 ashley.spagnuolo@startresearch.com

Mayo Clinic, Rochester

Recruiting

Rochester, Minnesota, United States, 55905

Contacts

855-776-0015

Cleveland Clinic, Taussig Cancer Institute

Recruiting

Cleveland, Ohio, United States, 44195

Contacts

216-444-7923 TaussigResearch@ccf.org

OU Health Stephenson Cancer Center

Recruiting

Oklahoma City, Oklahoma, United States, 73104

Sydney Kimmel Cancer Center

Recruiting

Philadelphia, Pennsylvania, United States, 19107

Contacts

Dennis Stone

215-955-6000 Dennis.Stone@jefferson.edu

NEXT Oncology

Recruiting

San Antonio, Texas, United States, 78229

Contacts

Jordan Georg

210-580-9521 jgeorg@nextoncology.com

NEXT Virginia, LLC

Recruiting

Fairfax, Virginia, United States, 22031

Contacts

Blake Patterson

703-783-4505 bpatterson@nextoncology.com

More Information

Sponsor

Kumquat Biosciences Inc.

Last update posted

Apr 23, 2026

Last verified

Apr, 2026

Keywords

cetuximab
KQB365
KQB198

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Kumquat Biosciences Inc. on 2026-04-23.