Castro Balado, AnaMondelo García, CristinaVarela Rey, IriaMoreda Vizcaíno, BeatrizSierra Sánchez, Jesús F.Rodríguez Ares, María TeresaHermelo Vidal, GonzaloZarra Ferro, IreneGonzález Barcia, MiguelYebra-Pimentel Vilar, EvaGiráldez Fernández, María JesúsOtero Espinar, Francisco JavierFernández Ferreiro, Anxo2020-12-152020-12-152020Castro-Balado, A.; Mondelo-García, C.; Varela-Rey, I.; Moreda-Vizcaíno, B.; Sierra-Sánchez, J.F.; Rodríguez-Ares, M.T.; Hermelo-Vidal, G.; Zarra-Ferro, I.; González-Barcia, M.; Yebra-Pimentel, E.; Giráldez-Fernández, M.J.; Otero-Espinar, F.J.; Fernández-Ferreiro, A. Recent Research in Ocular Cystinosis: Drug Delivery Systems, Cysteamine Detection Methods and Future Perspectives. Pharmaceutics 2020, 12, 1177http://hdl.handle.net/10347/23988Cystinosis is a rare genetic disorder characterized by the accumulation of cystine crystals in different tissues and organs. Although renal damage prevails during initial stages, the deposition of cystine crystals in the cornea causes severe ocular manifestations. At present, cysteamine is the only topical effective treatment for ocular cystinosis. The lack of investment by the pharmaceutical industry, together with the limited stability of cysteamine, make it available only as two marketed presentations (Cystaran® and Cystadrops®) and as compounding formulations prepared in pharmacy departments. Even so, new drug delivery systems (DDSs) need to be developed, allowing more comfortable dosage schedules that favor patient adherence. In the last decades, different research groups have focused on the development of hydrogels, nanowafers and contact lenses, allowing a sustained cysteamine release. In parallel, different determination methods and strategies to increase the stability of the formulations have also been developed. This comprehensive review aims to compile all the challenges and advances related to new cysteamine DDSs, analytical determination methods, and possible future therapeutic alternatives for treating cystinosiseng© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)Atribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/CystinosisOphthalmic administrationCysteamineDrug delivery systemsAnalytical chemistry methodsjournal article10.3390/pharmaceutics121211771999-4923open access