RBV-052B is a computationally designed Central Nervous System (CNS) drug candidate employing a prodrug strategy for blood-brain barrier (BBB) penetration followed by intraneuronal activation. This rabies prodrug candidate (SMILES: COC(CN(C)C)(COC)COC, MW: 191 Da) was designed using fixed-point string theory parameters (τ ∗ = 220) derived from the Quantum Entanglement Spacetime Theory (QuEST) framework. Safety assessment through the Cascade Interaction Liability Model (CELM) framework, testing 174 simultaneous biological targets including Human Analogue (102 targets) and Gut Model (72 targets), suggests minimal off-target liabilities and no severe predicted cascade toxicity events within the modeled system. RBV-052B achieves favorable physicochemical properties for CNS penetration (TPSA: 31 ˚A², zero hydrogen bond donors, CNS druggability score: 4/5) while utilizing a solvation trap mechanism for extended neuronal residence time. This compound represents a computationally supported approach to CNS drug delivery that may advance rabies treatment through physics-based molecular design, pending experimental confirmation.