doi:10.1080/10717544.2025.2484277engGonzález-Cela-Casamayor, AnaRodrigo, María J.MiriamBrugnera, MarcoMunuera, InésMartínez-Rincón, TeresaPrats-Lluís, CatalinaVillacampa, PilarGarcía-Feijoo, JuliánPablo, Luis E.Bravo-Osuna, IreneGarcia-Martin, ElenaHerrero-Vanrell, RocíoKetorolac, melatonin and latanoprost tri-loaded PLGA microspheres for neuroprotection in glaucomaART-2025-144315Glaucoma is a multifactorial neurodegenerative disease that affects the retina and optic nerve. The aim of this work was to reach different therapeutics targets by co-encapsulating three neuroprotective substances with hypotensive (latanoprost), antioxidant (melatonin) and anti-inflammatory (ketorolac) activity in biodegradable poly (lactic-co-glycolic acid) (PLGA) microspheres (MSs) capable of releasing the drugs for months after intravitreal injection, avoiding the need for repeated administrations. Multi-loaded PLGA MSs were prepared using the oil-in-water emulsion solvent extraction-evaporation technique and physicochemically characterized. PLGA 85:15 was the polymer ratio selected for the selected formulation. Tri-loaded MSs including vitamin E as additive showed good tolerance in retinal pigment epithelium cells after 24 h exposure (>90% cell viability). The final formulation (KMLVE) resulted in 33.58 ± 5.44 µm particle size and drug content (µg/mg MSs) of 39.70 ± 5.89, 67.28 ± 4.17 and 7.51 ± 0.58 for melatonin, ketorolac and latanoprost respectively. KMLVE were able to release in a sustained manner the three drugs over 70 days. KMLVE were injected at 2 and 12 weeks in Long-Evans rats (n = 20) after the induction of chronic glaucoma. Ophthalmological tests were performed and compared to not treated glaucomatous (n = 45) and healthy (n = 17) animals. Treated glaucomatous rats reached the lowest intraocular pressure, enhanced functionality of bipolar and retinal ganglion cells and showed greater neuroretinal thickness by optical coherence tomography (p < 0.05) compared to not treated glaucomatous rats at 24 weeks follow-up. According to the results, the tri-loaded microspheres can be considered as promising controlled-release system for the treatment of glaucoma.2025http://zaguan.unizar.es/record/16165910.1080/10717544.2025.2484277http://zaguan.unizar.es/record/161659oai:zaguan.unizar.es:161659info:eu-repo/grantAgreement/ES/AEI/PID2023-148219OB-C21info:eu-repo/grantAgreement/ES/AEI/PID2023-148219OB-C22info:eu-repo/grantAgreement/ES/ISCIII/JR22-00057info:eu-repo/grantAgreement/ES/ISCIII/RD21-0002-0050info:eu-repo/grantAgreement/ES/ISCIII/RD24-0007-0022info:eu-repo/grantAgreement/ES/MICINN/PID2020-113281RB-C21info:eu-repo/grantAgreement/ES/MICINN/PID2020-113281RB-C22Drug Delivery 32, 1 (2025), 2484277 [22 pp.]by-nchttps://creativecommons.org/licenses/by-nc/4.0/deed.esinfo:eu-repo/semantics/openAccess