1 Introduction STL Therapy is a cutting-edge cancer treatment that employs synthetic single-stranded positivesense RNA (ssRNA+) viruses with a complementary defect mechanism to target cancer cells with high precision, focusing on challenging cancers such as lung, liver, and brain. Designed for immediate implementation within the current biotechnology landscape (June 2025), STL Therapy utilizes mRNA platforms, viral vectors, and artificial intelligence (AI) to accelerate the transition from laboratory to clinical trials. With specific activation, robust safety features, and affordable costs, STL Therapy promises to be a practical solution to enhance cancer treatment outcomes. 1.1 Objectives • Eliminate cancer cells with high specificity, minimizing side effects. • Utilize existing technologies to conduct in vitro/in vivo trials within 6–12 months and Phase I clinical trials within 1–2 years. • Ensure safety with a robust “kill switch” mechanism and activation only in cancer cells. • Reduce costs to under $20,000 per patient, suitable for large-scale production. 2 Overview of STL Therapy STL Therapy is a synthetic RNA virus characterized by: • Complementary Defect Specificity: The RNA lacks an essential region (S2 domain), completed only in the presence of cancer-specific miRNAs (miR-21 and miR-145). • Therapeutic Payload: Carries the TRAIL gene (inducing apoptosis) and siRNA targeting VEGF (inhibiting tumor angiogenesis). 1 • Temporary Immune Evasion: Evades the immune system to reach target cells, then activates anti-cancer immunity post-treatment. • RNA Stability: Protected by 2’-O-Methylation, pseudouridine (Ψ), and stem-loops for survival in plasma and exosomes. • Safety Kill Switch: Self-destructs upon doxycycline exposure or after 7 days. • AI Integration: Analyzes patient data to optimize dosing and activation. The therapy targets lung, liver, and brain cancers (Stage III–IV), with potential expansion to other cancers after initial trials