SYS6006 in Combination With Enlonstobart Injection Versus Enlonstobart Injection in Participants With Advanced Solid Tumors

A Phase Ib/II Clinical Study to Evaluate the Safety and Efficacy of SYS6006 in Combination With Enlonstobart Injection Versus Enlonstobart Injection in Participants With Advanced Solid Tumors

This study is a Phase Ib/II clinical study. It includes two stages: Phase Ib and Phase II. In the Phase Ib stage, the primary objective is to evaluate the safety and tolerability of SYS6006 in combination with Enlonstobart Injection in participants with advanced solid tumors, and to provide a basis for dose selection in later clinical studies. The primary objective of the Phase II stage is to assess efficacy and safety of SYS6006 in combination with Enlonstobart Injection in participants with advanced solid tumors.

Study Overview

• Status: Not yet recruiting
• Conditions: Advanced Solid Tumors
• Intervention / Treatment: Biological: SYS6006; Biological: Enlonstobart

• Study Type: Interventional
• Enrollment (Estimated): 264
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Clinical Trials Information Group officer; Phone Number: 86-0311-69085587; Email: ctr-contact@cspc.cn

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• 1. Able to understand and voluntarily sign the written informed consent form (ICF);
• 2. Male or female subjects aged over 18 years old (inclusive).
• 3. Patients with solid tumor who have unresectable locally advanced or metastatic disease;
• 4. At least one measurable lesion, as defined by RECIST 1.1 criteria;
• 5. ECOG performance status of 0-2;
• 6. Expected survival ≥ 3 months;
• 7. Adequate function of major organs and bone marrow;
• 8. Women or man of childbearing potential must use highly effective contraception.

Exclusion Criteria:

• 1. Patients with metastases to meninges; with spinal cord compression; symptomatic and unstable brain metastasis;
• 2. Patients with a history of autoimmune diseases;
• 3. Presence of active infection (e.g., subjects are receiving anti-infection therapy);
• 4. Severe or uncontrolled cardiovascular disorder requiring treatment;
• 5. Women who are pregnant or breastfeeding.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SYS6006 + Enlonstobart; Phase Ib Dose Escalation Cohort Dose level 1 will consist of 3-6 patients who will receive SYS6006 and Enlonstobart. Dose level 2 will consist of 3-6 patients who will receive SYS6006 and Enlonstobart.; If 0/3 participants experience a DLT, the next 3 participants can be enrolled to receive the same dose regimen, and escalation to the next dose group may proceed;; If 1/3 participants experience a DLT, an additional 3 participants will be enrolled to continue evaluation at the same dose regimen:If a final total of 1/6 participants experience a DLT, escalation to the next dose group may proceed; If ≥2 of the 6 evaluable participants experience a DLT, escalation will be stopped;; If ≥2/3 participants experience a DLT, escalation will be stopped. Phase II Investigational Treatment:The maximum safe dose of SYS6006 in combination Enlonstobart (as determined in the phase Ib cohort).	Biological: SYS6006; Drug:SYS6006 Phase Ib dose level 1: SYS6006 Intramuscular injection; dose level 2: SYS6006 Intramuscular injection; Other Names: SYS6006 injection; Biological: Enlonstobart; Enlonstobart IV; Other Names: Enlonstobart injection
Active Comparator: Enlonstobart; Phase II Investigational Treatment:Enlonstobart Intravenous infusion	Biological: Enlonstobart; Enlonstobart IV; Other Names: Enlonstobart injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Phase Ib: Incidence and frequency of dose-limiting toxicities (DLTs) during the study (applicable to the combination therapy dose-escalation phase)	Within 21 days after the start of the treatment
Phase Ib: Incidence and frequency of treatment-emergent adverse events (TEAEs) .	Through study completion, an average of l year
Phase Ib:Incidence and frequency of serious adverse events (SAEs)	Through study completion, an average of l year
Phase Ib:Maximum tolerated dose (MTD)	Every 21 days while on treatment (estimated 6 months)
Phase Ib: Recommended Phase II dose (RP2D)	Every 21 days while on treatment (estimated 6 months)
Phase II: ORR as assessed by the investigator according to RECIST v1.1	through study completion, an average of 1year.
Phase II: Incidence and frequency of TEAEs.	through study completion, an average of l year
Phase II:Incidence and frequency of SAEs.	through study completion, an average of l year

Secondary Outcome Measures

Outcome Measure	Time Frame
Disease control rate (DCR) per RECIST 1.1	Up to approximately 24 months after the first participant is enrolled
Duration of response (DoR) per RECIST 1.1	Up to approximately 24 months after the first participant is enrolled
Progression free survival (PFS) per RECIST 1.1	Up to approximately 24months after the first participant is enrolled
Time to response(TTR)	Up to approximately 24months after the first participant is enrolled
Overall survival(OS)	Up to approximately 24 months after the first participant is enrolled
Frequency and severity of adverse events (AEs) (NCI CTCAE 5.0)	Up to approximately 24 months after the first participant is enrolled
PK parameters: The plasma concentration of enlonstobart	Up to approximately 24 months after the first participant is enrolled
Correlation between PD-L1 expression level (measured as Tumor Proportion Score [TPS] by 22C3 IHC assay) and objective response rate (ORR, as assessed by RECIST 1.1 criteria)	Up to approximately 24 months after the first participant is enrolled
To evaluate changes in cytokines such as interferon-alpha (IFNα) and the activation status of peripheral blood immune cells	through study completion, an average of l year

Collaborators and Investigators

• Sponsor: CSPC Megalith Biopharmaceutical Co.,Ltd.

Study record dates

Study Major Dates

• Study Start (Estimated): May 29, 2026
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): January 31, 2030

Study Registration Dates

• First Submitted: May 17, 2026
• First Submitted That Met QC Criteria: May 30, 2026
• First Posted (Actual): June 3, 2026

Study Record Updates

• Last Update Posted (Actual): June 3, 2026
• Last Update Submitted That Met QC Criteria: May 30, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: SYS6006 COVID-19 vaccine
• Other Study ID Numbers: SYS6006-009

Drug and device information, study documents

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