Development of pH-Sensitive Multiparticulates for Orally Disintegrating Tablets of Proton Pump Inhibitors: Physicochemical Characterization and Drug Release Studies.

Background/Objectives: Enteric coating protects active pharmaceutical ingredients from gastric degradation, but conventional tablets may present swallowing difficulties in geriatric and pediatric patients. Hence, this study intended to develop pH-responsive multiparticulates, formulated into orally disintegrating tablets (ODTs), for targeted intestinal drug delivery in individuals with dysphagia. Methods: Multiparticulates were developed via sequential seal coating, drug layering, sub-coating, and enteric coating on inert cores using a fluidized bed coater (Pam Glatt, India; bottom spray). Selected enteric-coated batches were directly compressed into ODTs using microcrystalline cellulose (Avicel PH102) and mannitol (Pearlitol SD 160) as fillers, with Explotab^®, Ac-Di-Sol^®, or crospovidone M^® as superdisintegrants. Results: Multiparticulates exhibited mean diameters of 197.671-529.511 μm and span values of 0.603-0.838. Span value < 1, indicating a narrow size distribution. Electron microscopy confirmed the spherical morphology of Batches 7a and b. Enteric-coated batches (5b, 6, 7a, 7b) released ≤10% of the drug in 0.1 N HCl at 2 h. Optimized formulation ODT 7b released 7.904% of the drug under gastric conditions and 79.749% in phosphate buffer (pH 6.8) within 2.5 h, following first-order drug release kinetics. ODT 7b demonstrated hardness (2.538 ± 0.144 kg/cm²), wetting time (11.17 ± 1.051 s), friability (0.712%), and drug content (99.81 ± 1.01%) within acceptable limits. Conclusions: The pH-dependent multiparticulates provided sustained intestinal drug release and, when incorporated into ODTs, yielded a dosage form with a rapid wetting time and acceptable mechanical properties. This dosage form can offer a promising approach for improving compliance and therapeutic efficacy in patients with swallowing difficulties (dysphagia).