Expanded Access Program to Provide STC-15 to Patients With Selected Advanced Cancer

1. Adult patients aged ≥18 years, or pediatricadolescent patients aged 12 to \<18 years with Sponsor medical approval, with a serious or life-threatening malignancy may be considered.
2. Patient has histologically, cytologically, or hematopathologically confirmed malignancy.
3. Disease is advanced, unresectable, metastatic, recurrent, relapsed/refractory, progressive, or otherwise not amenable to curative standard therapy.
4. The patient has no satisfactory approved therapy available or appropriate in the treating physician's judgment, has progressive disease after standard therapy, is intolerant of standard therapy, is medically ineligible for standard therapy, has declined standard therapy after informed discussion, and/or is being considered for STC-15 as a bridge-to-transplant, bridge-to-local therapy, or disease-control strategy.
5. Patient is not eligible for, cannot reasonably access, or cannot enroll in an ongoing STC-15 clinical trial within a clinically appropriate timeframe or a comparable investigational treatment.
6. Patient has active disease documented as applicable: recent imaging, marrow assessment, Minimal Residual Disease (MRD), circulating tumor/disease marker, biochemical marker, pathology/surgical assessment, clinical progression, or other disease-appropriate assessment. RECIST-measurable disease is preferred for solid tumors but is not required.
7. At least one recent baseline disease assessment is available or planned before STC-15 initiation where feasible.
8. Functional status is adequate to receive treatment and comply with treatment physician monitoring in the treating physician's and Sponsor's judgment.

0. Patient has adequate hepatic, renal, and coagulation function for STC-15 use, or has disease-related abnormalities judged acceptable by Sponsor medical review.

10. Patient can swallow, retain, and absorb oral STC-15, or has an acceptable enteral administration plan supported by Sponsor pharmacy/CMC review.

11. Prior systemic anticancer therapy, investigational therapy, radiotherapy, or surgery has been followed by a clinically acceptable washout/recovery period, considering half-life, overlapping toxicity, urgency, and treating physician/Sponsor judgment. Clinically significant prior-therapy toxicities should have recovered to Grade ≤2, baseline, or a stable clinically acceptable status, unless Sponsor medical review determines the residual toxicity does not materially increase STC-15 risk.

12. Medication list has been reviewed for CYP3A4 interactions, including azoles, macrolides, anticonvulsants, antibiotics, antivirals, herbal products, and other strong CYP3A4 inhibitors/inducers. Interacting medications must be discontinued, substituted, or specifically approved by Sponsor pharmacology/medical review.

13. Women of childbearing potential must agree to use effective contraception during treatment with STC-15 and for at least 30 days after the last dose of STC-15, or longer if required by local regulations.

14. Male patients with partners of childbearing potential must agree to use a condom during treatment with STC-15 and for at least 30 days after the last dose of STC-15, or longer if required by local regulations. Sperm donation is not allowed during treatment and for at least 30 days after the last dose of STC-15.

Exclusion criteria:

1. Patient is receiving concomitant systemic anticancer therapy. STC-15 must be administered as monotherapy under this protocol.
2. Patient is pregnant or breastfeeding or is unable or unwilling to comply with locally required contraception and pregnancy-prevention measures.
3. Patient has uncontrolled infection, infection requiring parenteral antimicrobial therapy that is not clinically stabilized, uncontrolled sepsis risk, or other infection risk judged unacceptable by the treating physician or Sponsor.
4. Patient has unstable cardiovascular disease, uncontrolled arrhythmia, symptomatic coronary disease, decompensated heart failure, uncontrolled hypertension, clinically significant pulmonary disease requiring recent hospitalization, uncontrolled seizure disorder, uncontrolled neurologic condition, or another serious uncontrolled illness that materially increases STC-15 risk in the opinion of the treating physician and the sponsor.
5. Patient has active, symptomatic, or unstable Central Nervous System (CNS) metastases or leptomeningeal disease requiring escalating steroids, urgent local therapy, or otherwise making systemic treatment unsafe. Stable/treated CNS disease may be allowed.
6. Patient has active clinically significant bleeding, a recent clinically significant bleeding event, an unstable platelet trajectory, or bleeding risk considered unacceptable by the treating physician or Sponsor.
7. Patient has unresolved clinically significant toxicity from prior therapy that would materially increase STC-15 risk, as judged by the treating physician or Sponsor. Stable Grade ≤2 toxicities may be allowed.
8. Patient has prior METTL3 inhibitor exposure associated with documented intolerance, treatment-related serious toxicity, or clear progression without benefit. Prior STC-15 treatment may be allowed for continuation/rollover if clinical benefit and acceptable safety are documented.
9. Patient has had major surgery within 30 days or radiotherapy within 14 days to STC-15 initiation such that unresolved toxicity, wound-healing risk, or overlapping toxicity is unacceptable, unless Sponsor approves the timing based on urgency and recovery status.
10. Patient has clinically significant malabsorption, uncontrolled vomiting, bowel obstruction, or another condition expected to prevent reliable oral/enteral STC-15 exposure.
11. Patient requires a strong CYP3A4 inhibitor or inducer that cannot be discontinued, substituted, or managed after Sponsor pharmacology/medical review.
12. Any condition, laboratory abnormality, psychiatric/substance-use issue, logistical barrier, or site limitation that, in the judgment of the treating physician or Sponsor, would make STC-15 treatment inappropriate or prevent informed consent, reliable administration, safety reporting, or provision of data required for Sponsor oversight of patient safety and treatment use.