Clinical Trial of TQB3126 for Safety, Tolerability, Pharmacokinetics and Preliminary Efficacy in Breast Cancer Subjects

Phase I/II Clinical Trial to Evaluate the Safety, Tolerability, Pharmacokinetics and Preliminary Efficacy of TQB3126 in Subjects With Breast Cancer

The trial comprises Phase I dose escalation/expansion and Phase II combination therapy. Using a multicenter, open-label, non-randomized design, breast cancer patients will receive TQB3126 to assess its safety, tolerability, pharmacokinetics and preliminary efficacy.

Study Overview

• Status: Not yet recruiting
• Conditions: Breast Cancer
• Intervention / Treatment: Drug: TQB3126

• Study Type: Interventional
• Enrollment (Estimated): 306
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Herui Yao, Doctor; Phone Number: +86 13500018020; Email: yaohrsysu@163.com

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510288
      • Sun Yat-sen Memorial Hospital, Sun Yat-Sen University
      • Contact: Herui Yao, Doctor; Phone Number: +86 13500018020; Email: yaohrsysu@163.com
    • Meizhou, Guangdong, China, 514000
      • Meizhou People's Hospital
      • Contact: Jingna Wu, Doctor; Phone Number: +86 13431819838; Email: 547511952@qq.com
  • Hubei
    • Wuhan, Hubei, China, 430000
      • Zhongnan Hospital of Wuhan University
      • Contact: Haijun Yu, Doctor; Phone Number: +86 13971665181; Email: doctoryhj@126.com
  • Hunan
    • Changsha, Hunan, China, 410000
      • The Third Xiangya Hospital of Central South University
      • Contact: Jun Zhang, Doctor; Phone Number: +86 13973131500; Email: 296864403@qq.com
  • Sichuan
    • Chengdu, Sichuan, China, 610041
      • Sichuan Cancer Hospital
      • Contact: Hao Wang, Doctor; Phone Number: +86 13518204307; Email: unique909@126.com
  • Tianjin Municipality
    • Tianjin, Tianjin Municipality, China, 300202
      • Tianjin Medical University Cancer Institute & Hospital
      • Contact: Yehui Shi, Doctor; Phone Number: +86 18622221183; Email: shiyehui@tjmuch.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Subjects voluntarily participate in this study, sign the informed consent form, and demonstrate good treatment compliance.
2. Aged 18 to 75 years at the time of informed consent signature; Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1; estimated survival expectancy of more than 3 months.
3. Histopathologically confirmed breast cancer.
4. Documented disease progression confirmed by clinical or imaging evidence during or after the most recent prior systemic therapy prior to the first study drug administration.
5. Have evaluable lesions per RECIST v1.1 criteria (measurable lesions; or bone-only metastases with at least one osteolytic or mixed lesion).
6. Adequate tissue samples shall be provided at screening for gene mutation testing to clarify genetic status.
7. Laboratory test results meet the criteria specified in the protocol (blood routine, liver and renal function, coagulation function, cardiac ultrasound Left Ventricular Ejection Fraction(LVEF) and other indicators are all within the protocol-specified ranges).
8. Subjects of childbearing potential must agree to use effective contraceptive measures throughout the study and for 6 months after study completion (the same requirement applies to male subjects); serum or urine pregnancy test result is negative within 7 days prior to enrollment.

Exclusion Criteria:

1. Other malignant tumors within 5 years prior to first dose, except those cured by single surgical treatment with at least 5 years of disease-free survival, or cured differentiated thyroid cancer, cervical carcinoma in situ, non-melanoma skin cancer, or superficial bladder tumors.
2. Conditions affecting intravenous access or blood sampling, or multiple factors affecting oral drug administration/absorption (e.g., inability to swallow, chronic diarrhea, intestinal obstruction).
3. Unresolved toxicity from prior therapy of Grade >1 (CTCAE v6.0), except Grade 2 alopecia, Grade 2 anemia, clinically insignificant laboratory abnormalities, or hypothyroidism stable on hormone replacement therapy.
4. Major surgery, significant traumatic injury within 4 weeks before first dose, anticipated need for major surgery during the study, or long-standing unhealed fracture.
5. Any bleeding event of Grade >=3 within 4 weeks before first dose.
6. Arterial/venous thrombotic events within 6 months before first dose (e.g., cerebrovascular accident, deep vein thrombosis, pulmonary embolism), excluding catheter-related or superficial venous thrombosis.
7. Active viral hepatitis that is poorly controlled (Hepatitis B Virus (HBV)/Hepatitis C Virus (HCV)-infected subjects meeting protocol-specified criteria may be enrolled).
8. Active syphilis infection requiring treatment.
9. Active tuberculosis, idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced or radiation pneumonitis requiring treatment, or history of/current interstitial lung disease (ILD).
10. History of psychotropic substance abuse unable to be discontinued, mental disorders, epilepsy requiring treatment, or severe psychiatric/neurological disease.
11. Planned or prior allogeneic bone marrow or solid organ transplantation.
12. Decompensated cirrhosis (Child-Pugh Class B or C) or history of hepatic encephalopathy.
13. Significant cardiovascular disease, including New York Heart Association(NYHA) Class >II heart failure, clinically significant ventricular arrhythmia, unstable angina, myocardial infarction within 12 months, markedly prolonged QT interval corrected by Fridericia's formula (QTcF), or personal/family history of congenital long QT syndrome.
14. Poorly controlled hypertension (resting systolic BP >=160 mmHg or diastolic BP >=100 mmHg on at least 2 measurements >=24 hours apart).
15. Active or uncontrolled serious infection (Grade >=2).
16. Renal failure requiring hemodialysis or peritoneal dialysis; or history of/current nephrotic syndrome (except cured) or chronic nephritis.
17. History of immunodeficiency, including HIV infection or other acquired/congenital immunodeficiency diseases.
18. Poorly controlled autoimmune disease requiring immunosuppressants or systemic corticosteroids for immunosuppression, continued within 7 days before first dose (except low-dose corticosteroids).
19. Clinically significant endometrial abnormalities (including hyperplasia, dysfunctional uterine bleeding, etc.).
20. Tumor-related conditions/treatments: anti-cancer therapy within 3 weeks before first dose or still within the drug's washout period; prior local radiotherapy not meeting protocol-specified interval or target lesion requirements; use of National Medical Products Administration (NMPA)-approved proprietary Chinese medicine with anti-tumor indications within 1 week before first dose; imaging showing tumor invasion of major vessels with risk of fatal hemorrhage; uncontrolled pleural effusion/ascites/moderate-or-greater pericardial effusion requiring repeated drainage; known leptomeningeal metastasis or uncontrolled brain metastasis symptoms; severe skeletal-related events due to bone metastases.
21. Known hypersensitivity to the study drug or its excipients.
22. Participation in and use of another investigational anti-tumor drug within 4 weeks before first dose.
23. Any concomitant disease or condition that, in the investigator's judgment, seriously endangers subject safety or study compliance, or any other reason making the subject unsuitable for enrollment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: TQB3126; Administered in accordance with the protocol	Drug: TQB3126; TQB3126 is a targeted protein degrader.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dose Limiting Toxicity (DLT)	DLT is defined as toxicities that meet pre-defined severity criteria (according to the NCI Common Terminology Criteria for Adverse Events (CTCAE) version 6.0) and are assessed as related to TQB3126, occurring from the first dose to the end of the first treatment cycle.	From first dose of TQB3126 to the end of Cycle 1, approximately 35 days.
Maximum Tolerated Dose (MTD)	MTD is defined as the highest dose at which DLT occurs in less than 33% of subjects.	From first dose of TQB3126 to the end of Cycle 1, approximately 35 days.
Recommended Phase II Dose (RP2D)	The dose recommended for Phase II study based on integrated safety, tolerability, pharmacokinetic and efficacy data.	Observation is expected to continue through Cycle 6 Day 28 throughout the study, around 6 months.
Adverse Events (AEs)	The occurrence, incidence and severity of all adverse events (AEs).	From the time of first dose of TQB3126 to 28 days after the last dose or until the start of other anti-tumor therapy, whichever occurs first.
Serious Adverse Events (SAEs)	The occurrence, incidence and severity of all serious adverse events (SAEs).	From the time of first dose of TQB3126 to 28 days after the last dose or until the start of other anti-tumor therapy, whichever occurs first.
Abnormal Incidence of Laboratory Test Indicators	Incidence and severity of abnormal laboratory values.	From the time of first dose of TQB3126 to 28 days after the last dose or until the start of other anti-tumor therapy, whichever occurs first.
Objective Response Rate (ORR)	The proportion of subjects with a best overall response of complete response (CR) or partial response (PR) according to RECIST v1.1.	From the date of first dose until the date of first documented disease progression, assessed up to approximately 3 years.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peak Concentration (Cmax)	Maximum observed plasma concentration of TQB3126.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Time to Reach Maximum Plasma Concentration (Tmax)	Time to reach the maximum plasma concentration of TQB3126.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Elimination Half-life (t1/2)	Elimination half-life of TQB3126 after oral dosing.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Area Under the Plasma Concentration-time Curve From Time Zero to Time t (AUC0-t)	Area under the plasma concentration-time curve from time zero to the last measurable concentration.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Area Under the Plasma Concentration-time Curve From Time Zero Extrapolated to Infinity (AUC0-∞)	Area under the plasma concentration-time curve from time zero extrapolated to infinity.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Apparent Clearance (CL/F)	Apparent total clearance of TQB3126 from plasma.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Apparent Volume of Distribution (Vz/F)	Apparent volume of distribution of TQB3126 in plasma.	Escalation: pre-dose+0.5,1,2,3,4,6,8,12,24,48,72,120 hours post single dose (Cycle0); pre-dose Cycle1 Day1. Expansion/combo: pre-dose+0.5-12 hours Cycle1 Day1; 24 hours Day2. All: pre-dose Day 7,14,21; pre-dose+0.5-12 hours Day 28; pre-dose Cycle2 Day1.
Clinical Benefit Rate (CBR)	The proportion of subjects with a best overall response of complete response, partial response, or stable disease lasting a pre-specified minimum duration, per RECIST v1.1.	From the date of first dose until the date of first documented disease progression, assessed up to approximately 3 years.
Disease Control Rate (DCR)	The proportion of subjects with a best overall response of complete response, partial response, or stable disease, per RECIST v1.1.	From the date of first dose until the date of first documented disease progression, assessed up to approximately 3 years.
Duration of Response (DOR)	The time from the first documentation of complete or partial response to the first documentation of disease progression.	From the date of first dose until the date of first documented disease progression, assessed up to approximately 3 years.
Progression-Free Survival (PFS)	The time from the first dose to the first documentation of disease progression or death from any cause, whichever occurs first.	From the date of first dose until the date of first documented disease progression, assessed up to approximately 3 years.
Time to Response (TTR)	The time from the first dose to the first documentation of complete or partial response.	From the date of first dose until the date of first documented disease progression, assessed up to approximately 3 years.

Collaborators and Investigators

• Sponsor: Chia Tai Tianqing Pharmaceutical Group Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): August 1, 2029
• Study Completion (Estimated): August 1, 2030

Study Registration Dates

• First Submitted: July 7, 2026
• First Submitted That Met QC Criteria: July 7, 2026
• First Posted (Actual): July 13, 2026

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 7, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Skin and Connective Tissue Diseases; Breast Neoplasms
• Other Study ID Numbers: TQB3126-I/II-01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No