SL-28 for Advanced Solid Tumours

Prior treatment

• Requirement for systemic corticosteroids or other immunosuppressive therapy that cannot be discontinued ≥14 days prior to dosing
• Prior therapies within restricted timeframes:
• Immune checkpoint inhibitors or biologics within 28 days
• Antineoplastic therapies, surgery, radiotherapy, or radiopharmaceuticals within 21 days
• Unapproved investigational drugs within 5 half-lives
• Concurrent malignancy within 5 years, except specified low-risk cancers
• Receipt of live vaccines within 28 days prior to screening
• Participation in another investigational study within 30 days prior to screening

Other illness

• NYHA Class III or IV heart disease, myocardial infarction within 6 months, unstable arrhythmia, or ischemia on ECG
• Active, uncontrolled bacterial, viral, or fungal infection requiring systemic therapy
• Known HIV, hepatitis B (HBsAg positive), or hepatitis C infection
• History of anaphylaxis or significant allergy interfering with participation
• Clinically significant cardiovascular, pulmonary, hepatic, renal, hematologic, gastrointestinal, endocrine, neurologic, psychiatric, or immunologic disease within 6 months
• Conditions affecting drug absorption, distribution, metabolism, or excretion

Other

• Ongoing toxicities ≥ Grade 2 per NCI CTCAE v5.0 (except alopecia, fatigue, sensory neuropathy, or adequately treated endocrine deficiencies)
• QTcF \>470 ms (females) or \>450 ms (males)
• Nitrosoureas or mitomycin C within 6 weeks
• Pregnancy or breastfeeding
• Inability or unwillingness to comply with protocol procedures

• Ability to provide written informed consent prior to any study-related procedures and to understand the nature, purpose, and potential risks of the study
• Adult males and females ≥18 years of age at screening
• Life expectancy of at least 3 months
• Histologically or cytologically confirmed unresectable advanced solid tumor (recurrent, metastatic, or locally advanced)
• Disease refractory to, intolerant of, or refusal of standard therapies, including immunotherapy and molecular/biomarker-directed treatments, as determined by the Principal Investigator (PI) or delegate
• Eligible tumor types include:
• Head and neck squamous cell carcinoma
• Thoracic malignancies (small-cell lung cancer, non-small cell lung cancer, esophageal cancer)
• Gastrointestinal malignancies (gastric, liver, colorectal, pancreatic adenocarcinoma)
• Genitourinary malignancies (bladder, renal cell, prostate cancer)
• Gynecologic malignancies (ovarian, endometrial cancer)
• Breast cancer and melanoma
• Evaluable disease per RECIST v1.1
• ECOG performance status 0-1 (or up to 2 at PI discretion)
• Adequate organ function, defined as:
• Total bilirubin ≤1.5 × ULN (≤2.0 × ULN for liver metastases or Gilbert's syndrome)
• AST, ALT, alkaline phosphatase ≤2.5 × ULN (≤5 × ULN if liver metastases, at PI discretion)
• Creatinine clearance ≥50 mL/min (Cockcroft-Gault) or eGFR ≥50 mL/min (CKD-EPI)
• Absolute neutrophil count ≥1,000/mm³
• Platelet count ≥100,000/mm³
• Hemoglobin ≥90 g/L without transfusion within 2 weeks
• Prothrombin time and aPTT ≤1.5 × ULN (or stable INR if on anticoagulation)
  • Female patients:
  • -Non-childbearing potential (surgically sterile or postmenopausal), or of childbearing potential with negative pregnancy tests and agreement to effective contraception through 90 days post-dose
  • Male patients:
• Agreement not to donate sperm for 90 days post-dose
• Agreement to use adequate contraception as applicable
• Suitable venous access for blood sampling
• Willingness and ability to comply with study procedures and protocol requirements