Skip to Main Content
Phase I

A Phase 1 Study of XB628 in Participants With Recurrent Advanced or Metastatic Solid Tumors

  • Study HIC#:2000040254
  • Last Updated:09/24/2025

This is a phase 1, first-in-human, open-label, dose-escalation study of XB628, a first-in-class bispecific antibody natural killer (NK) cell engager that targets NK group 2 member A (NKG2A), an inhibitory receptor on NK cells, and programmed cell death-ligand 1 (PD-L1).

    Contact Us

    For more information about this study, including how to volunteer, contact:

    Ingrid Palma

    Help Us Discover!

    You can help our team find trials you might be eligible for by creating a volunteer profile in MyChart. To get started, create a volunteer profile, or contact helpusdiscover@yale.edu, or call +18779788343 for more information.

    Trial Purpose and Description

    This study consists of a Dose-Escalation Stage. The Dose-Escalation Stage is designed to determine the maximum tolerated dose (MTD) and/or recommended dosage(s) for expansion (RDE[s]) of XB628 as a single agent.

    Eligibility Criteria

    Inclusion Criteria:

    • Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1.
    • Minimum life expectancy of ≥ 12 weeks.
    • Have a recurrent advanced or metastatic solid tumor that is histologically or cytologically confirmed.
    • Adequate organ and marrow function.
    • Not amenable to curative treatment with surgery or radiation.
    • Received at least 1 line of prior systemic anticancer therapy in the recurrent or metastatic setting.
    • Acceptable alternative therapy was received, refused, intolerable, or no longer effective.
    • Capable of understanding and complying with the protocol requirements and provide signed informed consent according to the protocol and local requirements.

    Exclusion Criteria:

    • Primary brain tumors or known active brain metastases.
    • Major surgery (eg, gastrointestinal surgery, removal or biopsy of brain metastasis) within 4 weeks before the first dose of study treatment.
    • Received radiation therapy within 1 week before the first dose of study treatment or clinically relevant ongoing complications from prior radiation therapy.
    • Received prior therapy targeting NK cells (eg, monalizumab).
    • A woman of childbearing potential has a positive serum pregnancy test within 7 days prior to study treatment.

    Principal Investigator

    Sub-Investigators

    For more information about this study, including how to volunteer, contact: