Development of topical eye-drops of lactoferrin-loaded biodegradable nanoparticles for the treatment of anterior segment inflammatory processes

Ocular inflammation is one of the most common comorbidities associated to ophthalmic surgeries and disorders. Since conventional topical ophthalmic treatments present disadvantages such as low bioavailability and relevant side effects, natural alternatives constitute an unmet medical need. In this sense, lactoferrin, a high molecular weight protein, is a promising alternative against inflammation. However, lactoferrin aqueous instability and high nasolacrimal duct drainage compromises its potential effectiveness. Moreover, nanotechnology has led to an improvement in the administration of active compounds with compromised biopharmaceutical profiles. Here, we incorporate lactoferrin into biodegradable polymeric nanoparticles and optimized the formulation using the design of experiments approach. A monodisperse nanoparticles population was obtained with an average size around 130 nm and positive surface charge. Pharmacokinetic and pharmacodynamic behaviour were improved by the nanoparticles showing a prolonged lactoferrin release profile. Lactoferrin nanoparticles were non-cytotoxic and non-irritant neither in vitro nor in vivo. Moreover, nanoparticles exhibited significantly increased anti-inflammatory efficacy in cell culture and preclinical assays. In conclusion, lactoferrin loaded nanoparticles constitute a safe and novel nanotechnological tool suitable for the treatment of ocular inflammation.