A Phase I Study of CS5007 in Participants With Advanced Solid Tumors

NCT07622524 | Not Yet Recruiting Phase 1

• 1 other identifier: CS5007-101
• Study Type: interventional
• Target: 310
• Locations: 2 countries
• Sites: 3

Brief Summary

This is a first-in-human (FIH), open-label, and multi-center Phase I study designed to evaluate the safety, tolerability, pharmacokinetics, and preliminary anti-tumor activity of CS5007 as monotherapy in participants with advanced solid tumors. The study is comprised of a Phase Ia dose escalation and Phase Ib dose expansion.

Conditions

Advanced Solid Tumors

Keywords

EGFR; HER3; Bispecific Antibody-Drug Conjugate; Phase I; Advanced Solid Tumors

Outcome Measures

Primary Outcomes (4)

• [Dose Escalation] Maximum tolerated dose (MTD) of CS5007

  Participants will receive CS5007 via intravenous (IV) infusion on Day 1 of repeated 21-day cycles (Q3W). The MTD will be determined, if any, by the number of participants who experience a dose limiting toxicity (DLT).

  Cycle 1 (Up to 21 Days)

• [Dose Escalation] Tentative recommended Phase II dose (RP2D) of CS5007

  The selection of tentative RP2D will be based on consideration of overall safety information together with available pharmacokinetic, pharmacodynamic, and efficacy data. The tentative RP2D may be the MTD or a lower dose within the tolerable dose range.

  Up to approximately 2 years

• [Dose Escalation] The incidence and severity of adverse events (AEs)

  Up to approximately 2 years

• [Dose Expansion] Objective response rate (ORR) evaluated by investigators per RECIST v1.1

  Up to approximately 2 years

Secondary Outcomes (13)

• [Dose Escalation & Expansion] Area under the curve (AUC) of CS5007

  Up to approximately 2 years

• [Dose Escalation & Expansion] Maximum concentration (Cmax) of CS5007

  Up to approximately 2 years

• [Dose Escalation & Expansion] Time to maximum concentration (Tmax) of CS5007

  Up to approximately 2 years

• [Dose Escalation & Expansion] Elimination half-life (t1/2) of CS5007

  Up to approximately 2 years

• [Dose Escalation & Expansion] Clearance (CL) of CS5007

  Up to approximately 2 years

Study Arms (2)

Dose Escalation

EXPERIMENTAL

Participants will be administered escalating doses of CS5007.

Drug: CS5007

Dose Expansion

EXPERIMENTAL

Participants will be administered the recommended dose(s) of CS5007 according to dose-escalation data.

Drug: CS5007

Interventions

CS5007 DRUG

CS5007 will be administered via intravenous (IV) infusion on Day 1 of repeated 21-day cycles (Q3W).

Dose Escalation; Dose Expansion

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Evidence of a personally signed and dated informed consent document.
• Willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures.
• Being ≥ 18 years of age on the day of signing informed consent.
• Pathologically or cytologically confirmed, unresectable advanced solid tumors.
• Participants must have at least one measurable lesion according to RECIST Version1.1.
• Eastern Cooperative Oncology Group (ECOG) Performance Score of 0 or 1.
• Adequate organ function.
• Life expectancy ≥ 3 months.
• Fertile men and women of childbearing potential must agree to use an effective method of birth control from providing signed consent and for 180 days after the last study drug administration

You may not qualify if:

• Has disease that is suitable for local treatment administered with curative intent.
• Has a history of a second malignancy active within the previous 3 years except for locally curable cancers that have been apparently cured.
• Known primary central nervous system (CNS) tumor or solid tumor CNS metastasis that is symptomatic, untreated, or requires therapy.
• Has life-threatening bleeding event or severe bleeding within 3 months prior to first dose.
• Has uncontrolled pleural effusion, pericardial effusion, or ascites.
• Has immune deficient disease or received systemic immunosuppressive treatment.
• Has intestinal obstruction,or history of inflammatory bowel disease,or chronic diarrhea.
• Has history of (non-infectious) interstitial lung disease/pneumonitis that required steroids.
• Has active infections requiring systemic therapy.
• Has significant cardiovascular disease or cerebrovascular accident within specified timeframes prior to first dose.
• Insufficient washout from prior anti-tumor therapy.
• Received live vaccine within 28 days prior to first dose.
• History of allogeneic organ or hematopoietic stem cell transplantation.
• History of hypersensitivity to excipients of study drug or any monoclonal antibody.
• Any toxic effects of prior therapy unresolved to Grade ≤1.

Sponsors & Collaborators

• CStone Pharmaceuticals: lead

Study Sites (3)

Icon Cancer Centre South Brisbane

South Brisbane, Queensland, 4101, Australia

Location

Linear Clinical Research

Nedlands, Western Australia, 6009, Australia

Location

Shanghai Chest Hospital

Shanghai, Shanghai Municipality, 200030, China

Location

Central Study Contacts

Sean Yao

CONTACT

+86 18616365940; yaosheng@cstonepharma.com

Study Design

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

Study Record Dates

• First Submitted: May 28, 2026
• First Posted: June 3, 2026
• Study Start: June 1, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2029
• Last Updated: June 3, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

AU (2); CN (1)