A Study of hSTC810 in Combination With Paclitaxel in Relapsed or Refractory Extensive Stage Small Cell Lung Cancer

A Phase Ib/II Study of hSTC810 in Combination With Paclitaxel in Relapsed or Refractory Extensive Stage Small Cell Lung Cancer

The purpose of this clinical study is to assess the safety and efficacy of hSTC810 and paclitaxel combination therapy in patients with relapsed or refractory extensive stage small cell lung cancer.

Study Overview

• Status: Terminated
• Conditions: Extensive Stage Small Cell Lung Cancer
• Intervention / Treatment: Drug: hSTC810 400 mg + Paclitaxel; Drug: hSTC810 800 mg + Paclitaxel

Detailed Description

The study will be conducted in 2 parts. Phase Ib will evaluate the safety of the combination of hSTC810 with a standard dose of paclitaxel using a 3+3 dose escalation design. Phase II will evaluate the efficacy of hSTC810 + paclitaxel combination therapy using a Simon 2-stage method.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• South Korea
  • Seoul, South Korea, 03080
    • Seoul National University Hospital
  • Seoul, South Korea, 05505
    • Asan Medical Center
  • Seoul, South Korea, 06351
    • Samsung Medical Center
  • Seoul, South Korea, 02841
    • Korea University Anam Hospital
  • Seoul, South Korea, 13620
    • Seoul National University Bundang Hospital
  • Suwon, South Korea, 16247
    • The Catholic University of Korea St. Vincent's Hospital
• United States
  • New York
    • New York, New York, United States, 10029
      • Tisch Cancer Institute at Mount Sinai
  • Texas
    • Houston, Texas, United States, 77030
      • MD Anderson Cancer Center

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Ability to understand and sign an informed consent form
• Male or female ≥ 18 years of age
• Histologically or cytologically confirmed SCLC
• R/R ES-SCLC on or after platinum-based chemotherapy for SCLC with documented disease progression
• At least 1 measurable lesion as defined by RECIST 1.1
• Eastern Cooperative Oncology Group Performance Score (ECOG PS) of 0 or 1
• Life expectancy of at least 3 months
• Adequate organ function as described in the protocol
• For female or male patients with reproductive potential: Agree to use contraception throughout the study and at least 5 months after the last dose.

Exclusion Criteria:

• Known active leptomeningeal disease (carcinomatous meningitis)
• Known active and uncontrolled central nervous system (CNS) metastases
• Treatment with immunotherapy, chemotherapy, targeted small molecule therapy, or any other investigational agent < 14 days prior to initiation of study treatment
• Treatment with radiation therapy < 14 days prior to initiation of study treatment
• Major surgery < 21 days prior to initiation of study treatment
• Received live vaccine < 30 days prior to initiation of study treatment, including intranasal influenza vaccine
• History of another primary malignancy with protocol-defined exceptions
• Active or history of autoimmune disease requiring systemic treatment
• Receiving high doses of steroids or other immunosuppressive medications
• Active hepatitis B or C infection
• Active or history of non-infectious pneumonitis requiring treatment with steroids
• Active uncontrolled viral, fungal, or bacterial infection including tuberculosis
• Pregnant or breastfeeding female patients
• History of severe hypersensitivity reaction to a monoclonal antibody treatment
• History of severe hypersensitivity reaction or ≥ Grade 3 adverse event (AE) to paclitaxel treatment
• History of cerebral vascular event, unstable angina, myocardial infarction, or cardiac symptoms within 6 months prior to screening
• QT Corrected for Fridericia's method (QTcF) > 470 ms at screening
• Lack of resolution of any toxicity to max Grade 1 (except alopecia)
• Active or history of any condition, therapy, or lab abnormality that may interfere with the patient participation for the full duration of the study
• Known psychiatric or substance use disorder
• Positive Coronavirus disease 2019 (COVID-19) test at screening

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: hSTC810 400 mg + Paclitaxel; hSTC810 400 mg will be administered with a standard dose of paclitaxel	Drug: hSTC810 400 mg + Paclitaxel; hSTC810 400 mg and paclitaxel 175 mg/m2 will be administered as an intravenous (IV) infusion Paclitaxel: 175 mg/m2 will be administered as an IV infusion
Experimental: hSTC810 800 mg + Paclitaxel; hSTC810 800 mg will be administered with a standard dose of paclitaxel	Drug: hSTC810 800 mg + Paclitaxel; hSTC810 800 mg and paclitaxel 175 mg/m2 will be administered as an IV infusion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Response Rate (ORR)	Percentage of patients with confirmed Confirmed Response (CR) or Partial Response (PR) as defined by RECIST 1.1 at 3 months	3 months
Progression Free Survival (PFS) rate	Proportion of patients without documented progression of disease and alive at 6 months	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety and tolerability	Incidence, causality, and nature of Treatment Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)	Up to 4 years
Overall Response Rate (ORR)	Investigator assessed ORR defined by RECIST 1.1	Up to 4 years
Duration of Response (DoR)	Time from the date of first documented CR or PR until the date of documented progression or death	Up to 4 years
Progression Free Survival (PFS)	Time from first dose until the date of objective disease progression or death	Up to 4 years
Clinical Benefit Rate (CBR)	Percentage of evaluable patients with CR, PR, or Stable Disease (SD) lasting ≥ 24 weeks	Up to 4 years
Overall Survival (OS)	Time from first dose of study drug until the date of death	Up to 4 years
Overall Survival (OS) rate	Proportion of patients alive at 12 months after the first dose of study drug	12 months
Maximum plasma concentration (Cmax)	Maximum plasma concentration of hSTC810 to evaluate PK parameters	Up to 21 days
Area under the concentration-time curve from 0 to 21 days (AUC0-21)	AUC from 0 to 21 days to evaluate PK parameters	Up to 21 days
Area under the concentration-time curve extrapolated from 0 to infinity (AUCo-inf)	AUC from time 0 to infinity to evaluate total drug exposure over time	Up to 21 days
Incidence of anti-drug antibodies (ADA)	Number and percentage of patients with positive ADAs	Up to 4 years

Collaborators and Investigators

• Sponsor: STCube, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): February 13, 2024
• Primary Completion (Actual): January 23, 2025
• Study Completion (Actual): August 25, 2025

Study Registration Dates

• First Submitted: August 17, 2023
• First Submitted That Met QC Criteria: August 24, 2023
• First Posted (Actual): August 29, 2023

Study Record Updates

• Last Update Posted (Estimated): September 5, 2025
• Last Update Submitted That Met QC Criteria: August 28, 2025
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Neoplasms; Lung Diseases; Neoplasms by Site; Respiratory Tract Neoplasms; Thoracic Neoplasms; Carcinoma, Bronchogenic; Bronchial Neoplasms; Lung Neoplasms; Small Cell Lung Carcinoma; Organic Chemicals; Hydrocarbons; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Terpenes; Taxoids; Cyclodecanes; Diterpenes; Paclitaxel
• Other Study ID Numbers: STCUBE-002

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