A Study of SI-B036 in Patients With Locally Advanced or Metastatic Breast Cancer and Other Solid Tumors

NCT07753226 | Not Yet Recruiting Phase 1

• 1 other identifier: SI-B036-103
• Study Type: interventional
• Target: 39
• Locations: 1 country
• Sites: 1

Brief Summary

This study is an open-label, multicenter, dose-escalation and expansion, non-randomized Phase I clinical study evaluating the safety, tolerability, pharmacokinetic characteristics and preliminary efficacy of SI-B036 bispecific antibody injection in patients with locally advanced or metastatic breast cancer and other solid tumors.

Conditions

Solid Tumor; Breast Cancer

Outcome Measures

Primary Outcomes (3)

• Phase Ia: Dose limiting toxicity (DLT)

  DLTs are assessed according to NCI-CTCAE v5.0 during the first cycle and defined as occurrence of any of the toxicities in DLT definition if judged by the investigator to be possibly, probably or definitely related to study drug administration.

  Up to 21 days after the first dose

• Phase Ia: Maximum tolerated dose (MTD)

  MTD is defined as the highest dose level at which no more than 1 in 6 participants experienced a DLT during the first cycle.

  Up to 21 days after the first dose

• Phase Ib: Recommended Phase II Dose (RP2D)

  The RP2D is defined as the dose level chosen by the sponsor (in consultation with the investigators) for phase II study, based on safety, tolerability, efficacy, PK, and PD data collected during the dose escalation study of SI-B036.

  Up to approximately 24 months

Secondary Outcomes (12)

• Treatment-Emergent Adverse Event (TEAE)

  Up to approximately 24 months

• Cmax

  Up to approximately 24 months

• Tmax

  Up to approximately 24 months

• T1/2

  Up to approximately 24 months

• AUC0-t

  Up to approximately 24 months

Study Arms (1)

SI-B036

EXPERIMENTAL

Participants receive SI-B036 for the first cycle (3 weeks). Participants with clinical benefit could receive additional treatment for more cycles. The administration will be terminated because of disease progression or intolerable toxicity occurring or other reasons.

Drug: SI-B036

Interventions

SI-B036 DRUG

Administration by intravenous infusion for a cycle of 3 weeks.

SI-B036

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Voluntarily sign the informed consent form and comply with the protocol requirements;
• No gender restriction;
• Age: ≥18 years and ≤75 years;
• Expected survival time ≥3 months;
• Locally advanced or metastatic breast cancer and other solid tumors;
• Agree to provide archived tumor tissue specimens from the primary or metastatic site within 2 years, or fresh tissue samples;
• Must have at least one measurable lesion as defined by RECIST v1.1;
• Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1;
• Toxicity from prior antitumor therapy must have recovered to ≤ Grade 1 as defined by NCI-CTCAE v6.0;
• No severe cardiac dysfunction, with left ventricular ejection fraction ≥50%;
• Organ function levels must meet the required criteria;
• Coagulation function: international normalized ratio ≤1.5, and activated partial thromboplastin time ≤1.5 × upper limit of normal;
• Urine protein ≤1+ or ≤1000 mg/24 h;
• For premenopausal women of childbearing potential, a pregnancy test must be performed within 7 days before starting treatment, with a negative serum pregnancy result, and they must be non-lactating; all enrolled patients (both males and females) must adopt adequate barrier contraceptive measures throughout the entire treatment period and for 6 months after treatment completion;
• The trial participant must be able and willing to comply with the protocol-specified visits, treatment plan, laboratory tests, and other study-related procedures.

You may not qualify if:

• Use of chemotherapy, biotherapy, immunotherapy, or similar treatments within 4 weeks or 5 half-lives prior to the first dose;
• Receipt of immunosuppressive drug therapy within 2 weeks prior to the first dose;
• History of severe cardiac or cerebrovascular disease;
• Prolonged QTc interval, complete left bundle branch block, third-degree atrioventricular block, or frequent and uncontrolled arrhythmias;
• Active autoimmune diseases and inflammatory diseases;
• Prior experience of ≥ Grade 3 toxicity related to anti-angiogenic therapy during previous anti-angiogenic treatment;
• Diagnosis of another solid tumor within 5 years prior to the first dose;
• Unstable thrombotic events requiring therapeutic intervention within 6 months prior to the first dose;
• Poorly controlled hypertension;
• Diabetes mellitus with poor glycemic control;
• History of interstitial lung disease (ILD) requiring steroid therapy, or current ILD, or ≥ Grade 2 radiation pneumonitis;
• Concurrent pulmonary disease resulting in severe impairment of respiratory function;
• Active central nervous system metastases;
• History of allergy to recombinant humanized antibodies or human-mouse chimeric antibodies, or allergy to any excipient component of SI-B036;
• Prior organ transplantation or allogeneic hematopoietic stem cell transplantation;

Sponsors & Collaborators

• Sichuan Baili Pharmaceutical Co., Ltd.: lead
• Baili-Bio (Chengdu) Pharmaceutical Co., Ltd.: collaborator

Study Sites (1)

Cancer Hospital Chinese Academy of Medical Sciences

Beijing, Beijing Municipality, China

Location

MeSH Terms

Conditions

Breast Neoplasms

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Central Study Contacts

Sa Xiao, PHD

CONTACT

+8615013238943; xiaosa@baili-pharm.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 4, 2026
• First Posted: August 7, 2026
• Study Start: August 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028
• Last Updated: August 7, 2026

Record last verified: 2026-08

Locations

CN (1)