Clinical trial NCT06952010: A Study of XB628 in Participants With Recurrent Advanced or Metastatic Solid Tumors
Official title: A Phase 1 Study of XB628 in Participants With Recurrent Advanced or Metastatic Solid Tumors
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: PHASE1
Conditions: Solid Tumor
Advanced Solid Tumor
Metastatic Solid Tumor
Immune Sensitive Tumor
Keywords: XB628
Solid tumor
Advanced solid tumor
Metastatic solid tumor
Immune sensitive tumor
PD-L1
Lead sponsor: Exelixis
Sponsor class: INDUSTRY
First posted: 2025-04-30
Enrollment: 75
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SEQUENTIAL
Primary purpose: TREATMENT

Brief summary: 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).

Detailed 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.

Primary outcomes:
measure: Number of Participants with Dose Limiting Toxicities (DLTs)
timeFrame: 21 days
measure: Number of Participants with Serious Adverse Events (SAEs), Treatment-emergent Adverse Events (TEAEs), and Adverse Events (AEs) Leading to Dose Withholding, Treatment Discontinuation, or Death
timeFrame: 27 months
Secondary outcomes:
measure: Area Under the Concentration-time Curve (AUC) of XB628
timeFrame: 25 months
measure: Maximum Plasma Concentration (Cmax) of XB628
timeFrame: 25 months
measure: Time to Maximum Concentration (Tmax) of XB628
timeFrame: 25 months
measure: Elimination Half-life (T1/2) of XB628
timeFrame: 25 months
measure: Apparent Clearance (CL/F) of XB628
timeFrame: 25 months
measure: Trough Concentration (Ctrough) of XB628
timeFrame: 25 months
measure: Number of Participants with Antidrug Antibody (ADA) Response to XB628
timeFrame: 25 months
measure: Objective Response Rate (ORR)
timeFrame: 27 months
measure: Duration of Response (DOR)
timeFrame: 27 months
measure: RDE for XB628
timeFrame: 25 months
Other outcomes:
Locations:
city: Hickory
country: United States
facility: Exelixis Clinical Site #1
state: North Carolina
city: San Antonio
country: United States
facility: Exelixis Clinical Site #2
state: Texas
Study officials:
References: