From Injection to Ingestion: Development of an Innovative Oral Delivery Platform for Injectable Therapeutics

Abstract

Injectable medicines remain indispensable for many therapeutic agents, particularly peptides, proteins, poorly permeable molecules, and drugs with inadequate gastrointestinal stability. However, repeated injections may cause discomfort, injection-site reactions, treatment fatigue, poor adherence, and reluctance to initiate or continue therapy. This research proposes an innovative pharmaceutical development strategy to transform suitable injectable therapeutics into orally administered formulations by integrating gastrointestinal protection, controlled release, permeation enhancement, and nanoscale drug delivery within a single oral platform. The proposed formulation-development approach begins with physicochemical and biopharmaceutical characterization of the selected injectable active pharmaceutical ingredient, followed by evaluation of its stability under simulated gastric and intestinal conditions. Researchers then develop a rational oral delivery system using an appropriate combination of protective polymers, absorption-enhancing excipients, and nanoscale or lipid-based carriers. Formulations are optimized according to particle size, polydispersity, surface charge, encapsulation efficiency, drug loading, gastrointestinal stability, dissolution behavior, and intestinal permeability. The optimized formulation is subsequently compared with the injectable reference using pharmacokinetic and, where appropriate, pharmacodynamic parameters. The primary outcome is an improvement in systemic exposure following oral administration while maintaining acceptable formulation stability and therapeutic activity. Secondary outcomes include improved protection against gastrointestinal degradation, enhanced intestinal transport, reproducible drug release, and reduced dependence on parenteral administration. The proposed platform is intended to provide a flexible framework rather than a single formulation applicable to every injectable drug. Its greatest potential lies in therapeutics for which oral delivery is limited primarily by instability, poor permeability, or both. Successful development could support a patient-centered transition from injection to ingestion and provide a broader strategy for reformulating selected injectable medicines into convenient oral dosage forms.