Allogeneic WTX-212C in Advanced Solid Tumors (WTX-212C-IIT)

A Multicenter, Open-label, Single-arm Phase I Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of Allogeneic WTX-212C Engineered Red Blood Cell Injection in Patients With Advanced Solid Tumors

This is a multicenter, open-label, single-arm Phase I study to evaluate the safety, tolerability, pharmacokinetics (PK), immunogenicity, and preliminary antitumor activity of allogeneic WTX-212C, an investigational allogeneic engineered red blood cell (RBC)-based product, in patients with advanced solid tumors who have failed standard therapies or have no available standard treatment options.

The study consists of a dose-escalation phase using a 3+3 design followed by a dose-expansion phase. Participants will receive allogeneic WTX-212C via intravenous infusion. Tumor assessments will be performed every 6 weeks according to RECIST 1.1.

Study Overview

• Status: Not yet recruiting
• Conditions: Advanced Solid Tumors
• Intervention / Treatment: Drug: allogeneic WTX-212C

Detailed Description

This Phase I study aims to characterize the safety profile, dose-limiting toxicities (DLTs), maximum tolerated dose (MTD), pharmacokinetics, immunogenicity, and preliminary efficacy of allogeneic WTX-212C in patients with advanced solid tumors.

The dose-escalation phase will follow a traditional 3+3 design with predefined dose levels. The dose-expansion phase will further evaluate safety, PK, and antitumor activity at selected dose levels.

Exploratory analyses will include immune profiling, tumor microenvironment assessment, and evaluation of biomarkers such as PD-1/PD-L1 expression, tumor mutational burden (TMB), and microsatellite instability (MSI) status.

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Yang Liu, PhD; Phone Number: 8613666601475; Email: Yangliuqq2003@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18-75 years
• Histologically or cytologically confirmed advanced solid tumors
• At least one measurable lesion per RECIST 1.1
• ECOG performance status ≤1
• Adequate organ function
• Life expectancy ≥12 weeks

Exclusion Criteria:

• Uncontrolled serious medical conditions
• Active or uncontrolled infections
• Symptomatic or unstable CNS metastases
• History of severe hypersensitivity to biologic agents
• Autoimmune diseases requiring systemic treatment
• Prior severe immune-related adverse events
• Conditions affecting red blood cell integrity

Study Plan

How is the study designed?

Design Details

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

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental: Allogeneic WTX-212C; Participants will receive allogeneic WTX-212C via intravenous infusion in dose-escalation and dose-expansion cohorts.	Drug: allogeneic WTX-212C; allogeneic WTX-212C is an investigational allogeneic engineered red blood cell-based injectable product administered intravenously.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Dose-Limiting Toxicities (DLTs)	Incidence of Dose-Limiting Toxicities (DLTs)	Within 21 days after the first dose
Incidence and Severity of Treatment-Related Adverse Events (TRAEs)	Incidence of Dose-Limiting Toxicities (DLTs)	Up to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximum Tolerated Dose (MTD)	MTD is defined as the highest dose level at which no more than 1 out of 6 participants experiences a dose-limiting toxicity (DLT) during the first treatment cycle, based on a standard 3+3 dose-escalation design.	Within 21 days after the first dose
Pharmacokinetic Parameters (Cmax)	Plasma pharmacokinetic parameters of allogeneic WTX-212C, including maximum observed concentration (Cmax）will be estimated using non-compartmental analysis methods.	From first dose up to 12 months
Objective Response Rate (ORR)	ORR is defined as the proportion of participants achieving a confirmed complete response (CR) or partial response (PR) according to RECIST version 1.1 criteria, based on investigator assessment.	Up to 12 months
Disease Control Rate (DCR)	DCR is defined as the proportion of participants achieving complete response (CR), partial response (PR), or stable disease (SD) according to RECIST version 1.1 criteria.	Up to 12 months
Progression-Free Survival (PFS)	PFS is defined as the time from the first dose of allogeneic WTX-212C to the first documented disease progression according to RECIST version 1.1 or death from any cause, whichever occurs first.	Up to 12 months
Incidence of Anti-Drug Antibodies (ADA)	The incidence of anti-drug antibodies (ADA) against allogeneic WTX-212C will be assessed using validated immunoassays.	From baseline up to 12 months
Pharmacokinetic Parameters (AUC)	Plasma pharmacokinetic parameters of allogeneic WTX-212C，area under the concentration-time curve (AUC), will be estimated using non-compartmental analysis methods.	From first dose up to 12 months
Pharmacokinetic Parameters (Tmax)	Plasma pharmacokinetic parameters of allogeneic WTX-212C, time to maximum concentration (Tmax) will be estimated using non-compartmental analysis methods.	From first dose up to 12 months
Pharmacokinetic Parameters (T1/2)	Plasma pharmacokinetic parameters of allogeneic WTX-212C, and terminal elimination half-life (t1/2) will be estimated using non-compartmental analysis methods.	From first dose up to 12 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in Immune Cell Subsets in Peripheral Blood	Quantitative and phenotypic analysis of peripheral blood immune cell subsets (e.g., T cells, B cells, NK cells) will be performed using flow cytometry to assess immunological changes following treatment.	From baseline up to 12 months
Exposure-Response Relationship	The relationship between pharmacokinetic exposure parameters (e.g., Cmax, AUC) and clinical outcomes (safety and efficacy endpoints) will be explored using descriptive and model-based analyses.	Up to 12 months

Collaborators and Investigators

• Sponsor: Zhejiang Provincial People's Hospital
• Collaborators: First People's Hospital of Hangzhou; Westlake Therapeutics

Study record dates

Study Major Dates

• Study Start (Estimated): April 10, 2026
• Primary Completion (Estimated): April 9, 2027
• Study Completion (Estimated): April 9, 2028

Study Registration Dates

• First Submitted: April 6, 2026
• First Submitted That Met QC Criteria: April 21, 2026
• First Posted (Actual): April 29, 2026

Study Record Updates

• Last Update Posted (Actual): April 29, 2026
• Last Update Submitted That Met QC Criteria: April 21, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Immunotherapy; Phase I; Solid Tumor; Engineered Red Blood Cells; Allogeneic Engineered Red Blood Cell; uRBC
• Other Study ID Numbers: WTX-212C-uRBC-IIT-001CN

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No