Prodrugs in Modern Medicine: Strategies, Applications, and Future Directions

Prodrugs are pharmacologically inactive compounds that undergo enzymatic or chemical transformation in vivo to release active drugs. This strategy has emerged as a powerful tool in modern drug development, addressing key limitations such as poor solubility, limited bioavailability, rapid metabolism, and systemic toxicity. This review provides a comprehensive overview of prodrug classifications, including carrier-linked, bio-precursor, and self-immolative systems, and their applications across therapeutic areas such as oncology, infectious diseases, and cardiovascular disorders. It explores historical developments, rational design strategies (e.g., mutual, co-drugs, double prodrugs), and molecular targeting approaches including enzyme-, pH, and redox-sensitive systems. Additionally, it discusses macromolecular and nanoparticle-based prodrugs and evaluates key challenges in stability, activation variability, and toxicity from released promoieties. Emphasis is also placed on emerging trends such as biorthogonal activation, probiologics, and machine learning-guided design. By integrating advances in nanotechnology, precision medicine, and computational modeling, prodrugs are poised to transform therapeutic delivery in increasingly targeted and patient-specific ways.