Advanced Solid TumorPhase 1/2NCT07751042
Phase 1/2 Study of Intravenous Injection of STX-003 in Advanced Solid Tumors as Monotherapy or in Combination With Pembrolizumab
A Phase 1/2 study testing STX-003 and KEYTRUDA® in people with Advanced Solid Tumor, run by Strand Therapeutics Inc. at 4 sites in 2 countries.
Trial summary
Phase 1/2, Open-label, Multi-center, First-in-human Study of the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics and Anti-tumor Activity of STX-003 Delivered by Intravenous Injection in Patients with Advanced Solid Tumors as a Monotherapy or in Combination with Pembrolizumab. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Advanced Solid Tumor
- What is being tested?
- STX-003 and KEYTRUDA®
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 220 participants
- Where
- 4 sitesin 2 countries
- Study dates
- 30 Jun 2026to 15 Nov 2030
- Phase
- Phase 1/2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Mentally competent and able to understand and sign the ICF.
- Tumor type for which there is an FDA-approved anti-PD-1/L1 antibody therapy, specifically including biomarker labeled subsets (i.e. PD-L1+) as well as anatomical subsets in some disease (cutaneous melanoma is eligible whereas acral, mucosal and uveal are not; Phase 1) and advanced cutaneous melanoma or PD-L1+ NSCLC.
- Histologically or cytologically documented, locally advanced, or metastatic solid tumor.
- At least one measurable lesion per RECIST v1.1 criteria.
- The patient lacks a curative therapy or has progressive disease despite, or refused, standard therapy.
- ECOG performance status of 0 or 1.
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- Life expectancy of ≥ 12 weeks per the Investigator.
- ≥ 18 years of age at the time of informed consent.
- Body weight ≥ 40 kg.
- WOCBP and males with female partners of child-bearing potential must agree to use adequate birth control throughout their participation and for 3 months following the last dose of STX-003.
- Willing and able to comply with protocol required assessments.
- Hematology:
- ANC ≥ 1,000 cells/mm3.
- Platelet count ≥ 75,000 cells/mm3.
- Hemoglobin ≥ 8.0 g/dL.
- Renal: Serum creatinine < 1.5 × ULN or creatinine clearance ≥ 40 mL/min based on the Cockcroft-Gault glomerular filtration rate estimation
- Coagulation:
- PT/INR or PT must be ≤ 1.5 × ULN.
- aPTT ≤ 1.5 × ULN unless undergoing anticoagulation therapy.
- Liver:
- Albumin ≥ 3.5 g/dL or within the normal range of the local reference laboratory.
- AST and ALT < 2 × ULN.
- Bilirubin ≤ 1.5 × ULN (except participants with documented Gilbert's syndrome who may be enrolled if the conjugated bilirubin is within normal limits) or ≤ 5 × ULN with liver metastases.
- Phase 2 Inclusion Criteria
- 13. NSCLC :
- Histologically or cytologically documented findings consistent with NSCLC not amenable to curative surgery, radiation, or other therapy.
- Biomarker confirmed as PD-L1+ per local institutional standard practice.
- Patients with known activating EGFR, STK11 or KEAP1 mutations as well as ALK/ROS1 fusions, are not eligible.
- Prior treatment (for advanced, metastatic or [neo]adjuvant) should have included a platinum-based therapy and a PD-1/L1 pathway checkpoint inhibitor, unless the patient is not a candidate for or has refused viable therapies due to inability to tolerate treatment (i.e. cell therapy) or potential side effects (i.e. checkpoint inhibitor toxicity).
- 14. Melanoma : Histologically or cytologically documented findings consistent with advanced cutaneous melanoma not amenable to curative surgery, radiation, or other therapy. Acral, mucosal and uveal melanoma are excluded.
- Patients who are not candidates for or have refused available therapies due to inability to tolerate treatment (i.e. cell therapy) or potential side effects (i.e. checkpoint inhibitor toxicity) are also eligible.
- Received an anti-PD-1/PD-L1 inhibitor as monotherapy or in combination with anti-CTLA-4 inhibitor and have either primary or secondary checkpoint inhibitor resistance asper SITC consensus definition, unless deemed intolerable by the Investigator. Patients with BRAF V600E mutant melanoma should have received a BRAF inhibitor as monotherapy or in combination with other targeted agents (MAPK kinase MEK inhibitors), unless deemed intolerable by the Investigator.
Who cannot join
- Medical Conditions
- History of primary immune deficiency.
- History of clinically significant autoimmune disease that has required intervention in the last 6 months. Consultation with the MM may inform the discussion of whether autoimmune disease is clinically significant.
- History of Grade 3 or higher IRAEs that has not resolved to Grade ≤ 1 at the time of enrollment. Exceptions include endocrine disorders that are well-managed with stable physiological hormone replacement and Grade 3 immune-related rash. Patients meeting this criterion may be considered for enrollment following approval by the MM.
- History of solid organ transplant and taking immunosuppressive medications.
- Cardiovascular exclusions
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- Medical history of an arterial thrombotic event, stroke, or transient ischemic attack within the past 6 months.
- Medical history of symptomatic congestive heart failure (New York Heart Association classes II-IV) or a cardiac arrhythmia that required treatment within the past 6 months.
- Medical history of myocardial infarction or unstable angina within 6 months before C1D1.
- Recent medical concerns exclusions
- Evidence of active infection requiring IV antibiotics within 7 days prior to C1D1.
- Active uncontrolled bleeding, or a bleeding diathesis within 7 days prior to C1D1.
- Serious or non-healing wound, fistula, skin ulcer, or non-healing bone fracture within 7 days prior to C1D1.
- Known 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 CNS tumor, epidural tumor or metastasis, or brain metastasis. Patients with any primary CNS malignancy including glioma and current, active, or 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 (MRI or CT scan) during the Screening period and are off systemic steroids (for at least 2 weeks prior to first dose).
- Another primary malignancy that has not been treated with curative intent (discuss with MM), 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.
- Major surgery within 4 weeks of first dose of study drug.
- Any condition that, in the opinion of the Investigator, would interfere with evaluation of the investigational product or interpretation of the patients' safety or study results.
- 4. Prior/Concomitant Therapy
- Prior treatment with STX-003 or other VEEV-based replicating RNA.
- Prior IL-12 therapy.
- Receipt of any live vaccine within 30 days prior to the first dose of study treatment.
- Use of another systemic anticancer therapy within 3 weeks prior to C1D1 or 5 halflives, whichever is shorter or use of radiotherapy within 1 week prior to C1D1 5. Prior/Concurrent Clinical Study Experience
- Previously enrolled in this study.
- Actively enrolled in another clinical study unless it is an observational (noninterventional) clinical study or the follow-up component of an interventional study.
- Known severe hypersensitivity (Grade ≥ 3) to study treatment or any of the excipients of the products.
- Other Exclusions
- History of interstitial lung disease or active, non-infectious pneumonitis (combination cohorts only).
- Known psychiatric or substance use disorder that would interfere with the patient's ability to cooperate with the requirements of the study.
- Currently pregnant (confirmed with a positive pregnancy test), breast-feeding or planning to become pregnant within 6 months following treatment. For WOCBP, a negative serum β-HCG result must be available within a 72-hour window before the first treatment dose.
Trial locations and contacts
4 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
4 sites in 2 countries
United States3 sites, 3 recruiting
- Not yet recruiting
Massachusetts General Hospital
Boston, Massachusetts, 02114
Justin Gainor, MD
- Recruiting
Sarah Cannon Research Institute
Nashville, Tennessee, 37203
Ashley Maheu, 615-329-7274, ashley.maheu@scri.com
Melissa Johnson, MD
- Recruiting
HonorHealth Research Institute
Scottsdale, Arizona, 85258
Amy Stolldastice, 602-570-2383, astollstadice@honorhealth.com
Justin Moser, MD
Australia1 site, 1 recruiting
- Not yet recruiting
Melanoma Institute Australia
Wollstonecraft, New South Wales, 2065
Georgina Long, AO, BSc (Hons1, UM), PhD, MBBS, +61 2 9911 7336, georgina.long@sydney.edu.au
About this study
Official title: A Phase 1/2, Open-label, Multi-center, First-in-human Study of the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics and Antitumor Activity of STX-003 Delivered Intravenously in Patients With Advanced Solid Tumors as a Monotherapy or in Combination With Pembrolizumab
Phase 1/2, Open-label, Multi-center, First-in-human Study of the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics and Anti-tumor Activity of STX-003 Delivered by Intravenous Injection in Patients with Advanced Solid Tumors as a Monotherapy or in Combination with Pembrolizumab.
Read the detailed description
This open-label, Phase 1/2, first-in-human (FIH), multiple ascending dose and dose expansion study involves STX-003 administration, alone or in combination with pembrolizumab, to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary antitumor activity in patients with advanced cancers. (Update after review)
- Conditions
- Advanced Solid Tumor
- Being tested
- STX-003, KEYTRUDA®
- Keywords
- Intravenous, Non Small Cell Lung Cancer, Melanoma, Advanced Solid Tumors, mRNA
- Medical subject headings
- Carcinoma, Non-Small-Cell Lung, Melanoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
STX-003Biological
STX-003 is a LNP formulated self-replicating mRNA encoding the therapeutic payload human IL-12 (hIL-12) with miRNA target sites to sense specific endogenous miRs.
KEYTRUDA®Biological
Pembrolizumab (Keytruda USPI 2026) is a marketed PD-1 blocking humanized monoclonal IgG4 kappa antibody.
| Study group | Role | What they receive |
|---|---|---|
| Phase 1 Monotherapy | Experimental | STX-003 administered intravenously, at ascending doses across sequential cohorts, once per cycle for up to 35 cycles (approximately 24 months). Receives: Biological: STX-003 |
| Phase 1 Combination (STX-003 with Pembrolizumab) | Experimental | STX-003 administered intravenously, at ascending doses across sequential cohorts, once per cycle in combination with pembrolizumab for up to 35 cycles (approximately 24 months). Receives: Biological: STX-003; Biological: KEYTRUDA® |
| Phase 2 Monotherapy (STX-003) | Experimental | STX-003 administered intravenously, at 4 planned dose expansion cohorts in patients with advanced cancers with high unmet need, once per cycle for up to 35 cycles (approximately 24 months). Receives: Biological: STX-003 |
| Phase 2 Combination (STX-003 with Pembrolizumab) | Experimental | STX-003 administered intravenously, at 4 planned dose expansion cohorts in patients with advanced cancers with high unmet need, once per cycle for up to 35 cycles (approximately 24 months). Receives: Biological: STX-003; Biological: KEYTRUDA® |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of TEAEs, SAEs, and DLTs
Measured: From time of informed consent until 30 days after the last dose of investigational product.
Occurrence of changes from baseline in patients' clinical safety laboratory values and vital signs to assess the safety and tolerability of STX-003.
Collection and analysis of changes in data from baseline of patients' safety laboratory values (chemistry, hematology, coagulation, complement (Bb \& C3a), urinalysis, and lipids). Vital signs will include Temperature: (degrees Fahrenheit) Pulse: (beats per minute) Respiratory rate: (breaths per minute) Blood pressure: (systolic and diastolic each reported in mmHg) Oxygen saturation by pulse oximetry: (percentage (SpO2, %))
Measured: From Day 1 until 30 days after last dose of STX-003
Secondary outcomes (6)
Assessment of PK and PD in patients dosed with STX-003
Area under the concentration curve (AUC)
Measured: Day 1,2,3,4,8,15,22,23,24,25,29,36, 43,44,51,58
Number and nature of preliminary antitumor activity of STX-003 as monotherapy and in combination with Pembrolizumab.
Measured: From time of informed consent until 30 days after the last dose of investigational product.
Assessment of Tumor infiltrating lymphocytes
Tumor biopsies will be analyzed by immunohistochemistry to assess tumor-infiltrating lymphocytes (TILs) in the tumor microenvironment, including density of CD4 and CD8 positive cells and PD-L1 expression.
Measured: From time if informed consent until 30 days after the last dose of investigational product (STX-003)
Objective Response Rate (ORR) in patients with advanced solid tumors.
Measured: From time of informed consent until 30 days after the last dose of investigational product.
Assessment of PK and PD in patients dosed with STX-003
Maximum observed plasma concentration (Cmax) of STX-003
Measured: Day 1,2,3,4,8,15,22,23,24,25,29,36, 43,44,51,58
Changes from baseline in vital signs
Vital signs will include Temperature: (degrees Fahrenheit) Pulse: (beats per minute) Respiratory rate: (breaths per minute) Blood pressure: (systolic and diastolic each reported in mmHg) Oxygen saturation by pulse oximetry: (percentage (SpO2, %))
Measured: From Day 1 until 30 days after last dose of STX-003.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Aug 2026
- Study start30 Jun 2026
- Primary completion17 Jul 2030 (estimated)
- Study completion15 Nov 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Advanced Solid TumorStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 220 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Strand Therapeutics Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07751042
- Sponsor's protocol ID
- STX-003-01
- Status last verified
- Aug 2026
- First submitted
- 6 Apr 2026
- Last updated
- 2 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No