A Phase I Clinical Study of SSS59 Monotherapy in Patients With Advanced Malignant Tumors

A Phase I Clinical Study of the Safety, Pharmacokinetics, and Antitumor Activity of SSS59 in Patients With Advanced Malignant Tumors

This study was an open-label phase I study to evaluate the safety, pharmacokinetics, and antitumor activity of SSS59 as a single agent in patients with advanced malignancies.

Study Overview

• Status: Recruiting
• Conditions: Malignant Tumors
• Intervention / Treatment: Drug: SSS59

Detailed Description

This study includes 4 Parts: Part A1 (dose escalation and dose extension for QW administration), Part A2 (dose escalation and dose extension for Q2W administration), Part A3 (dose extension for Q3W administration), and Part B (indication extension, such as advanced gastric or gastroesophageal junction adenocarcinoma with MUC17 positive, failure of standard therapy, or intolerance to standard therapy , or other tumors).

• Study Type: Interventional
• Enrollment (Estimated): 154
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Qi Li, MD; Phone Number: 86+13818207333; Email: Leeqi2001@hotmail.com

Study Locations

• China
  • Shanghai
    • Shanghai, Shanghai, China
      • Recruiting
      • Shanghai First People's Hospital
      • Contact: Wenqian Geng; Phone Number: 86+021-36126254; Email: shiyilunli@sina.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Histologically and/or cytologically documented local advanced or recurrent or metastatic malignancies.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.
• Expected survival >3 months.
• Signed informed consent form.
• Must have adequate organ function.

Exclusion Criteria:

• Any remaining AEs > grade 1 from prior anti-tumor treatment as per CTCAE v5. 0, with exception of hair loss and fatigue.
• Pregnant or nursing women or women/men who are ready to give birth.
• symptomatic central nervous system metastasis.
• Allergy to other antibody drugs or any excipients in the study drugs.
• Underwent major surgery within 4 weeks prior to first dosing.
• The patient is participating in another clinical study, unless it is an observational (non-intervention) clinical study or a follow-up period of an intervention study.

The above information was not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A1; Dose escalation will be conducted using accelerated titration and traditional 3+3 design. Dose Escalation Level includes 12 levels, QW IV. Dose extension will be carried out at the selected level.	Drug: SSS59; A humanized antibody targeting MUC17
Experimental: Part A2; Dose escalation will be conducted using a traditional 3+3 design. Dose Escalation Level includes 12 levels, Q2W IV. Dose extension will be carried out at the selected level.	Drug: SSS59; A humanized antibody targeting MUC17
Experimental: Part A3; Dose extension will be carried out at the selected dose level, Q3W, IV.	Drug: SSS59; A humanized antibody targeting MUC17
Experimental: Part B; Indication extension will be carried out at the selected level.	Drug: SSS59; A humanized antibody targeting MUC17

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
DLTs	Dose limiting toxicity	21 days
Safety and tolerability	Safety and tolerability assessed by incidence and severity of adverse events	during the intervention，Within 28 days of the last dose
MTD and RP2D	Determine the maximum tolerated dose and determine the recommended phase II dose	through study completion, an average of 2 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cmax of SSS59	Maximum concentration	baseline, during the intervention and at the end of the study
Tmax of SSS59	Time to peak drug concentration	baseline, during the intervention and at the end of the study
AUC0-last of SSS59	the area under the curve (AUC) up to the last measurable concentration	baseline, during the intervention and at the end of the study
RO of SSS59	Receptor Occupancy	baseline, during the intervention and at the end of the study
Pharmacodynamic (PD) characteristics of SSS59	change of cytokine	baseline, during the intervention and at the end of the study
Immunogenicity of SSS59	ADA，NAB（if ADA is positive）	baseline, during the intervention and at the end of the study
Preliminary antitumor activity of SSS59	Assessed according to Recist V1.1	baseline, during the intervention and at the end of the study

Collaborators and Investigators

• Sponsor: Shenyang Sunshine Pharmaceutical Co., LTD.

Study record dates

Study Major Dates

• Study Start (Actual): April 27, 2025
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): December 31, 2027

Study Registration Dates

• First Submitted: April 10, 2025
• First Submitted That Met QC Criteria: April 23, 2025
• First Posted (Actual): April 25, 2025

Study Record Updates

• Last Update Posted (Actual): April 29, 2025
• Last Update Submitted That Met QC Criteria: April 27, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms
• Other Study ID Numbers: SSS59-101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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