Phase I Study of Becotatug Vedotin for Safety and Efficacy in EGFR-Positive Pediatric Relapsed/Refractory or Metastatic Solid Tumors (MRG003)

May 7, 2026 updated by: Yizhuo Zhang, Sun Yat-sen University

A Phase I Clinical Study to Explore the Safety and Efficacy of Becotatug Vedotin in Pediatric Patients With EGFR-Positive Relapsed/Refractory or Metastatic Solid Tumors

There is a significant unmet medical need for effective therapies for pediatric relapsed/refractory solid tumors. EGFR is highly and stably expressed in multiple pediatric solid tumor subtypes, and adult Phase I data of Becotatug Vedotin demonstrated a manageable safety profile and promising antitumor activity in EGFR-positive advanced solid tumors.This is a multicenter, non-randomized, single-arm, open-label Phase I clinical trial sponsored by Sun Yat-sen University Cancer Center (SYSUCC). The trial evaluates the safety, tolerability, pharmacokinetics (PK), immunogenicity, and preliminary efficacy of Becotatug Vedotin-an EGFR-targeted antibody-drug conjugate (ADC)-in pediatric patients with EGFR-positive relapsed/refractory or metastatic solid tumors.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Pediatric relapsed/refractory solid tumors represent a major unmet medical need, with conventional chemotherapy and immunotherapy showing limited efficacy and significant toxicities in this population. EGFR is highly and stably expressed in multiple pediatric solid tumor subtypes. Becotatug Vedotin consists of a humanized anti-EGFR monoclonal antibody conjugated to monomethyl auristatin E (MMAE), a potent microtubule inhibitor, via a cleavable valine-citrulline linker. Adult Phase I data demonstrated a manageable safety profile and promising antitumor activity in EGFR-positive advanced solid tumors, with an objective response rate (ORR) of 29% in nasopharyngeal carcinoma and 31% in head and neck squamous cell carcinoma. This trial extends these findings to the pediatric population.The trial evaluates the safety, tolerability, pharmacokinetics (PK), immunogenicity, and preliminary efficacy of Becotatug Vedotin-an EGFR-targeted antibody-drug conjugate (ADC)-in pediatric patients with EGFR-positive relapsed/refractory or metastatic solid tumors.

Study Type

Interventional

Enrollment (Estimated)

51

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • China
    • Guangdong
      • Guangzhou, Guangdong, China, 510060
        • Recruiting
        • Sun yat-sen University Cancer Center
        • Contact:
        • Principal Investigator:
          • Yizhuo Zhang

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • All participants must meet all of the following criteria to be eligible for enrollment:

Informed Consent: The patient (and/or legal guardian, as age-appropriate) fully understands the study, voluntarily agrees to participate, and signs a written informed consent form (ICF). A separate biomarker consent form is required for EGFR testing prior to screening.

Age: 2 to 18 years old at the time of consent. Life Expectancy: Estimated overall survival of at least 3 months.

Histologically Confirmed Disease: Pathologically confirmed relapsed/refractory or metastatic EGFR-positive solid tumor, belonging to one of the following subtypes:

Head and neck squamous cell carcinoma, nasopharyngeal carcinoma, or lymphoepithelial carcinoma that progressed during or after at least one line of platinum-based chemotherapy and PD-1/PD-L1 inhibitor therapy Rhabdomyosarcoma Neuroblastoma Medulloblastoma Wilms tumor Atypical teratoid/rhabdoid tumors (AT/RTs) Diffuse intrinsic pontine gliomas (DIPGs) Other EGFR-positive solid tumor subtypes deemed eligible by the investigator Measurable Disease: At least one measurable tumor lesion by computed tomography (CT) or magnetic resonance imaging (MRI) per RECIST v1.1 criteria (longest diameter ≥10 mm; pathological lymph node short axis ≥15 mm).

Performance Status: Eastern Cooperative Oncology Group (ECOG) performance status score of 0, 1, or 2.

Adequate Bone Marrow Function:

Absolute neutrophil count (ANC) ≥1.5 × 10⁹/L Platelet count ≥75 × 10⁹/L Hemoglobin ≥80 g/L Exception for patients with bone marrow involvement: ANC ≥1.0 × 10⁹/L, platelets ≥50 × 10⁹/L, hemoglobin ≥75 g/L

Adequate Hepatic and Renal Function:

Serum creatinine ≤1.5 × upper limit of normal (ULN) Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5 × ULN Total bilirubin ≤1.5 × ULN Exception for patients with liver involvement: AST/ALT ≤5 × ULN, total bilirubin ≤3 × ULN

Exclusion Criteria:

  • Participants will be excluded from the study if they meet any of the following criteria:

Hypersensitivity: Known hypersensitivity to any component of Becotatug Vedotin (MRG003) or its excipients.

Symptomatic CNS Metastases: Presence of symptomatic central nervous system (CNS) metastases.

Prior Malignancies: History of other primary malignant tumors, except for:

Locally excised basal cell or squamous cell carcinoma of the skin Cervical carcinoma in situ Any prior malignancy that has been in complete remission for ≥3 years without treatment Note: Melanoma (any stage) is explicitly excluded

Significant Liver Disease: Clinically significant liver disease, including:

Positive hepatitis C virus (HCV) antibody Chronic active hepatitis B (HBV DNA >20,000 IU/mL) HIV Infection: Known human immunodeficiency virus (HIV) infection. Severe Ocular Abnormalities: History of severe ophthalmologic conditions, such as severe dry eye syndrome or exposure keratitis.

Uncontrolled Systemic Diseases: Severe or uncontrolled medical conditions, including:

Interstitial lung disease or pneumonitis Active autoimmune diseases requiring systemic immunosuppressive therapy

Cardiac Disease: Clinically significant cardiac dysfunction or cardiac disease, including:

Congestive heart failure (New York Heart Association Class ≥II) Uncontrolled arrhythmias QTc interval prolongation >450 ms (males) or >470 ms (females) Recent Antitumor Therapy: Received any systemic antitumor therapy (chemotherapy, biological therapy, immunotherapy, targeted therapy) within 3 weeks prior to the first dose of study drug, and have not recovered to CTCAE v4.03 Grade ≤1 (except alopecia).

Recent Major Surgery: Underwent major surgical procedure within 3 weeks prior to the first dose of study drug.

Planned Surgery: Planned surgical procedure during the study period, or any surgery deemed necessary by the investigator.

Prior EGFR Therapy Toxicity: History of severe skin toxicity caused by prior EGFR-targeted therapy, or chronic skin disease requiring ongoing oral or intravenous treatment.

Other Significant Risks: Any other concurrent medical condition that, in the investigator's judgment, would increase the risk of toxicity or compromise the patient's ability to complete the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Becotatug Vedotin (MRG003) Phase I Dose-Escalation & Expansion in EGFR-Positive Pediatric R/M Solid

This is a single-arm, open-label study where all enrolled participants receive Becotatug Vedotin (MRG003), a novel EGFR-targeted antibody-drug conjugate (ADC), as monotherapy.

Intervention Details Study Drug: Becotatug Vedotin (MRG003) for Injection Route of Administration: Intravenous (IV) infusion over 30 minutes to 3 hours Dosing Schedule: Every 3 weeks (Q3W) on Day 1 of each 21-day cycle Maximum Treatment Duration: Up to 8 cycles (24 weeks)

Dose Levels:

Ia Dose-Escalation Phase: 4 planned dose levels (1.0, 1.5, 2.0, 2.3 mg/kg) Starting dose: 1.0 mg/kg (modified accelerated titration design, 1 patient per cohort) Subsequent doses: Standard 3+3 design Ib Dose-Expansion Phase: All patients receive the determined Recommended Phase II Dose (RP2D)
Drug: Becotatug Vedotin
Study Drug: Becotatug Vedotin (MRG003) for Injection (lyophilized powder, 20 mg/vial) Route: Intravenous (IV) infusion over 30 minutes to 3 hours Schedule: Every 3 weeks (Q3W) on Day 1 of each 21-day cycle Maximum Treatment Duration: Up to 8 cycles (24 weeks); patients with confirmed clinical benefit (objective response or stable disease) may continue treatment beyond 8 cycles until disease progression, unacceptable toxicity, withdrawal of consent, or study termination

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of dose-limiting toxicities
Time Frame: First 21-day treatment cycle (Cycle 1)

DLTs are defined as treatment-related adverse events or laboratory abnormalities (excluding hypersensitivity reactions) that meet CTCAE v4.03 grade 3-4 criteria and occur during the first 21 days of treatment, including:

  • Grade 4 neutropenia lasting >7 days
  • Grade 3 thrombocytopenia lasting >7 days or any grade 4 thrombocytopenia
  • Grade 3 febrile neutropenia requiring antibiotic therapy
  • Grade 3-4 hepatic, renal, cardiovascular, ocular, or neurological toxicities
  • Uncontrolled grade 3-4 skin, gastrointestinal, or other systemic toxicities
First 21-day treatment cycle (Cycle 1)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sun Yat-sen University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

May 30, 2026

Primary Completion (Estimated)

May 30, 2027

Study Completion (Estimated)

May 30, 2028

Study Registration Dates

First Submitted

May 7, 2026

First Submitted That Met QC Criteria

May 7, 2026

First Posted (Actual)

May 13, 2026

Study Record Updates

Last Update Posted (Actual)

May 13, 2026

Last Update Submitted That Met QC Criteria

May 7, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • MRG003-pediatirc-001
  • Sun Yat-sen University Cancer (Other Identifier: Sun Yat-sen University Cancer)

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

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Nasopharyngeal Carcinoma

Clinical Trials on Becotatug Vedotin

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Austria

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe