Phase 1/2 Study of Intratumoral Injection of STX-001 in Advanced Solid Tumors as Monotherapy or in Combination With Pembrolizumab

NCT06249048 | Recruiting Phase 1 DMC FDA Drug

• 1 other identifier: STX-001-01
• Study Type: interventional
• Target: 108
• Locations: 2 countries
• Sites: 7

Brief Summary

Phase 1/2, Open-label, Multi-center, First-in-human Study of the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics and Anti-tumor Activity of STX-001 Delivered by Intratumoral Injection in Patients with Advanced Solid Tumors as a Monotherapy or in Combination with Pembrolizumab. The study now includes a monotherapy cohort targeting visceral lesions and a separate Phase 2 monotherapy cohort for advanced melanoma.

Conditions

Advanced Solid Tumor

Keywords

Intratumoral; Triple Negative Breast Cancer; Melanoma; Advance Solid Tumors; mRNA

Outcome Measures

Primary Outcomes (2)

• Number and nature of dose-limiting toxicities (DLTs), treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs) in patients with advanced solid tumors.

  The occurrence of DLTs, TEAEs, and SAEs will be used to determine the maximum tolerated dose and recommended Phase 2 dose of STX-001.

  From time of informed consent until 30 days after the last dose of investigational product (STX-001).

• Occurrence of changes from baseline in patients' clinical safety laboratory values and vital signs to assess the safety and tolerability of STX-001.

  Collection and analysis of changes in data from baseline of patients' vital signs (temperature, pulse, respiratory rate, blood pressure, oxygen saturation via pulse oximetry) as well as clinical safety laboratory values (chemistry, hematology, coagulation, complement (Bb \& C3a), urinalysis, and lipids).

  From time of informed consent until 30 days after the last dose of investigational product (STX-001).

Secondary Outcomes (9)

• Assessment of PK in patients dosed with STX-001

  From time of informed consent until 30 days after the last dose of investigational product (STX-001).

• Assessment of Tumor infiltrating lymphocytes (TILs)

  From time of informed consent until 30 days after the last dose of investigational product (STX-001).

• Number and nature of preliminary antitumor activity of STX-001.

  From time of informed consent until 30 days after the last dose of investigational product (STX-001).

• Number and nature of preliminary antitumor activity of STX-001 in combination with pembrolizumab.

  From time of informed consent until 30 days after the last dose of investigational product (STX-001).

• Number and nature of preliminary antitumor activity of STX-001.

  From time of informed consent until 18 months after the last dose of investigational product (STX-001).

Study Arms (5)

Phase 1 Monotherapy (STX-001)

EXPERIMENTAL

A Phase 1, first-in-human (FIH), multiple ascending dose administration of intratumoral STX-001 monotherapy to evaluate safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) and preliminary antitumor activity in patients with advanced cancers. Consists of four planned dose-escalation cohorts (Cohorts 1m) plus permitted backfill enrollment (up to 30 patients). New patients are enrolled in each dose escalation cohort, and dose escalation may be stopped early if emerging PK or safety data warrant it. Dose extension and treatment pauses are integrated, with a maximum extension of 35 cycles (≈24 months).

Biological: STX-001

Phase 1 Combination (STX-001 with Pembrolizumab)

EXPERIMENTAL

A Phase 1, first-in-human (FIH), multiple ascending STX-001 dose administration, in combination with pembrolizumab, to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary antitumor activity in patients with advanced cancers. Consists of 4 planned dose escalation cohorts (Cohorts 1c) of STX-001and pembrolizumab given concurrently, with new patients enrolled in each dose escalation cohort. Dose escalation may be halted early if PK or safety data indicate, and the dose extension period extends up to 35 cycles with treatment pauses. Backfill enrollment is permitted up to 30 patients.

Biological: STX-001; Biological: Keytruda®

Phase 2 Combination (STX-001 with Pembrolizumab)

EXPERIMENTAL

Phase 2 consists of dose expansion cohorts in patients with 2 defined cancer types: triple negative breast cancer (TNBC) and melanoma. Phase 2 will evaluate STX-001 in combination with pembrolizumab; the recommended Phase 2 dose (RP2D) of STX-001 will be selected based on analysis of the totality of data from Phase 1 safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) and preliminary efficacy data. Dose extension and treatment pauses are incorporated.

Biological: STX-001; Biological: Keytruda®

Phase 1 Visceral-lesion Monotherapy (Cohort 1Vm)

EXPERIMENTAL

Phase 1, first-in-human (FIH) monotherapy cohort targeting visceral lesions. STX-001 is administered intratumorally at 30 µg, 100 µg and 300 µg to evaluate safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary antitumor activity in patients with advanced cancers. Cohort 1Vm is part of the dose escalation stage; new patients are enrolled at each dose level, and backfill enrollment is permitted up to 30 patients. Dose escalation may be stopped early if PK or safety data warrant it.

Biological: STX-001

Phase 2 Advanced-Melanoma Monotherapy

EXPERIMENTAL

Phase 2 dose expansion cohort evaluating STX-001 monotherapy administered intratumorally to patients with advanced melanoma. Assesses safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary antitumor activity with the recommended dose selected based on Phase 1 data. Dose extension and treatment pauses are allowed up to 35 cycles.

Biological: STX-001

Interventions

STX-001 BIOLOGICAL

STX-001 encapsulates a self-replicating RNA encoded for IL-12, contained within an LNP for intratumoral injection. Injections may be administered into multiple lesions according to protocol-defined procedures.

Phase 1 Combination (STX-001 with Pembrolizumab); Phase 1 Monotherapy (STX-001); Phase 1 Visceral-lesion Monotherapy (Cohort 1Vm); Phase 2 Advanced-Melanoma Monotherapy; Phase 2 Combination (STX-001 with Pembrolizumab)

Keytruda® BIOLOGICAL

Pembrolizumab (Keytruda USPI 2023) is a marketed PD-1 blocking humanized monoclonal IgG4 kappa antibody.

Also known as: Pembrolizumab

Phase 1 Combination (STX-001 with Pembrolizumab); Phase 2 Combination (STX-001 with Pembrolizumab)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• ≥ 18 years of age at the time of screening.
• Mentally competent and able to understand and sign the informed consent form (ICF).
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Life expectancy of ≥ 12 weeks per the Investigator.
• Body weight ˃ 40 kg.
• At least 4 weeks from any prior major surgery.
• Willing and able to provide blood samples prior to the start of this study.
• Has a tumor lesion amenable to injection, must be accessible for pre and post injection biopsy, and the patient must be willing to consent to biopsy, if deemed safe by the Investigator.
• Laboratory values (Hematology): Absolute neutrophil count ≥ 1,000 cells/mm3; Platelet count ≥ 75,000 cells/mm3; Hemoglobin ≥ 8.0 g/dL.
• Laboratory values (Renal): Serum creatinine \< 1.5 × upper limit of normal (ULN) or creatinine clearance ≥ 40 mL/min based on the Cockcroft-Gault glomerular filtration rate estimation
• Laboratory values (Coagulation): Prothrombin/International Normalized Ratio (PT/INR) or prothrombin time must be \< 1.5 × ULN;
• Activated partial thromboplastin time (aPTT) ≤ 1.5 × ULN unless undergoing anticoagulation therapy.
• Laboratory values (Liver): Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) \< 2 × ULN; Bilirubin ≤ 2 × ULN or ≤ 5 × ULN for all patients.
• Histologically or cytologically documented, locally advanced, or metastatic solid tumor.
• Disease progression confirmed by imaging or other objective evidence after having received standard treatment or patients with refractory solid tumors. Patients must have progressed or are intolerant of at least one line of prior therapy.

You may not qualify if:

• History of primary immune deficiency.
• History of autoimmune disease and/or requiring immunosuppression (except hypothyroidism).
• History of History of Grade 3 or higher immune-related adverse events. Patient may be enrolled with Medical Monitor approval.
• History of solid organ transplant and taking immunosuppressive medications.
• Prior direct radiation therapy to the tumor lesion to be injected.
• Active use of systemic anticoagulants
• Evidence of active infection requiring intravenous (IV) antibiotics during screening requiring therapy within 7 days prior to Cycle 1 Day 1.
• Active uncontrolled bleeding, or a bleeding diathesis within 7 days prior to Cycle 1 Day 1.
• Serious or non-healing wound, fistula, skin ulcer, or non-healing bone fracture within 7 days prior to Cycle 1 Day 1.
• Known human immunodeficiency virus (HIV) infection, active hepatitis B infection, or hepatitis C infection.
• Virology evaluation should be conducted at screening to include serum HIV antibody, HBc antibody, HBsAg antigen, and HCV antibody. Patients with a positive antibody evaluation for HCV and/or HBc should undergo evaluation to measure HCV RNA or HBV DNA, respectively.
• Untreated central nervous system tumor, epidural tumor or metastasis, or brain metastasis. Patients with any primary Central Nervous System (CNS) malignancy including glioma and current, active, progressing CNS malignancy, including carcinomatosis meningitis are excluded.
• Patients with treated brain metastases are eligible if there is no evidence of progression for at least 4 weeks after CNS-directed treatment, as ascertained by clinical examination and brain imaging (magnetic resonance imaging \[MRI\] or computed tomography \[CT\] scan) during the screening period and off systemic steroids (for at least 2 weeks prior to first dose).
• Another primary malignancy that has not been treated with curative intent, except for non-metastatic cutaneous basal cell or squamous cell carcinoma, or non-muscle invasive bladder cancer.
• Serious illness considered by the Investigator as incompatible with participating in this clinical study.

Sponsors & Collaborators

• Strand Therapeutics Inc.: lead

Study Sites (7)

HonorHealth Research and Innovation Institute

Scottsdale, Arizona, 85258, United States

NOT YET RECRUITING

NextGen Oncology

Beverly Hills, California, 90212, United States

RECRUITING

Cleveland Clinic

Cleveland, Ohio, 44195, United States

NOT YET RECRUITING

University of Pittsburgh Medical Center

Pittsburgh, Pennsylvania, 15232, United States

RECRUITING

The University of Texas MD Anderson Cancer Center

Houston, Texas, 77030, United States

RECRUITING

Huntsman Cancer Institute - University of Utah

Salt Lake City, Utah, 84112, United States

NOT YET RECRUITING

Melanoma Institute Australia

Wollstonecraft, Australia

RECRUITING

MeSH Terms

Conditions

Triple Negative Breast Neoplasms; Melanoma

Interventions

pembrolizumab

Condition Hierarchy (Ancestors)

Breast Neoplasms; Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Neuroendocrine Tumors; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms by Histologic Type; Neoplasms, Nerve Tissue; Nevi and Melanomas; Skin Neoplasms

Study Officials

• Jason Luke, MD

  Strand Therapeutics

  STUDY CHAIR

Central Study Contacts

S Thomas, MS

CONTACT

617-993-9281; stx001.inquiry@strandtx.us

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 2, 2024
• First Posted: February 8, 2024
• Study Start: May 3, 2024
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): November 1, 2028
• Last Updated: October 29, 2025

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1); US (6)