Open Actively Recruiting

Study of MT-5111 in HER2-positive Solid Tumors


Brief Summary

This will be a Phase 1b, first in human, open-label, dose escalation and expansion study of MT-5111 (a recombinant fusion protein) given as monotherapy in subjects with HER2-positive solid tumors

Primary Purpose
Study Type
Phase I


Healthy Volunteers
Minimum Age
18 Years
Maximum Age

Inclusion Criteria:

  • Histologically confirmed, unresectable, locally advanced or metastatic solid cancers:
    • Part A (Dose-Escalation): All HER2-positive solid cancers are eligible
    • Part B (Dose-Expansion): Any type of HER2-positive solid cancer, including breast cancer, and gastric or gastroesophageal adenocarcinomas (GEA).
  • HER2-positive in the latest tumor sample tested for HER2 (testing to be done on a metastatic lesion in cases of metastatic cancers).
  • Relapsed or refractory to or intolerant of existing therapy(ies)
  • At least 1 measurable or evaluable lesion according to RECIST 1.1 (Subjects with evaluable disease only may be included in the dose escalation phase)
  • ECOG performance score of ≤ 1
  • Adequate Bone marrow function as determined by:
    • Absolute neutrophil count (ANC) ≥ 1,000/mm3
    • Platelet count ≥ 75,000 mm³ and
    • Hemoglobin ≥ 8.0 g/dL
    • Red blood cell transfusion within 2 weeks of study treatment start is allowed if hemoglobin levels remain stable
  • Kidney function:
    • Creatinine clearance (CLcr) ≥ 50 mL/min either measured or estimated using the Cockcroft-Gault formula
  • Cardiac Function:
    • Left ventricular ejection fraction (LVEF) ≥ 55% on the echocardiogram (ECHO) assessment (preferred), or multigated acquisition (MUGA) scan, and QTcF ≤ 480 ms for women and QTcF ≤ 450 ms for men [average from three QTcF values on the triplicate 12-lead electrocardiogram (ECG)] at baseline
  • Hepatic function:
    • Total bilirubin ≤ 1.5 x ULN, or ≤ 3 x ULN for subjects with Gilbert's Syndrome and
    • AST ≤ 3 x ULN (or ≤ 5 x ULN if liver metastasis) and ALT ≤ 3 x ULN (or ≤ 5 x ULN if liver metastasis)

Exclusion Criteria:

  • History or current evidence of another tumor that is histologically distinct from the tumor under study
  • Current evidence of new or growing CNS metastases during screening
    • Subjects with known CNS metastases will be eligible if they meet protocol specified criteria
  • Evidence of CTCAE Grade >1 toxicity before the start of treatment, except for hair loss and those Grade 2 toxicities listed as permitted in other eligibility criteria
  • History or evidence of significant cardiovascular disease
  • Current evidence of active, uncontrolled hepatitis B virus, hepatitis C virus, human immunodeficiency virus (HIV) (evidenced by detectable viral load by PCR) or acquired immunodeficiency syndrome (AIDS) related illness
  • Current evidence of ≥ grade 2 underlying pulmonary disease
  • Certain exclusionary prior treatments

Join this Trial

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Study Stats
Protocol No.
Lisa Yonemoto
  • TRIO-US - Fullerton
  • TRIO-US - Hollywood FL
  • TRIO-US - Los Alamitos CA
  • TRIO-US - Orlando FL
  • UCLA Santa Monica
For Providers
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