Bochot A, Lajavardi L, Camelo S, Bourges J-L, Behar-Cohen F, de Kozak Y, Fattal E
UMR CNRS « physico-chimie-pharmacotechnie-biopharmacie », faculté de pharmacie, université Paris-Sud, Châtenay-Malabry, France.
Ann Pharm Fr. 2011 Mar;69(2):100-7. doi: 10.1016/j.pharma.2010.11.002. Epub 2011 Jan 13.
Intravitreal administration has been widely used since 20 years and has been shown to improve the treatment of diseases of the posterior segment of the eye with infectious origin or in edematous maculopathies. This route of administration allows to achieve high concentration of drug in the vitreous and avoids the problems resulting from systemic administration. However, two basic problems limit the use of intravitreal therapy. Many drugs are rapidly cleared from the vitreous humor; therefore, to reach and to maintain effective therapy repeated injections are necessary. Repeated intravitreal injections increase the risk of endophthalmitis, damage to lens, retinal detachment. Moreover, some drugs provoke a local toxicity at their effective dose inducing side-effects and possible retinal lesions. In this context, the development and the use of new drug delivery systems for intravitreal administration are necessary to treat chronic ocular diseases. Among them, particulate systems such as liposomes have been widely studied. Liposomes are easily injectable and permit to reduce the toxicity and to increase the residence time of several drugs in the eye. They are also able to protect in vivo poorly-stable molecules from degradation such as peptides and nucleic acids. Some promising results have been obtained for the treatment of retinitis induced by cytomegalovirus in human and more recently for the treatment of uveitis in animal. Finally, the fate of liposomes in ocular tissues and fluids after their injection into the vitreous and their elimination routes begin to be more known.
玻璃体内给药已广泛应用了20年，已被证明可改善对眼后段具有感染性起源的疾病或水肿性黄斑病变的治疗。这种给药途径能够在玻璃体中达到高药物浓度，并避免全身给药带来的问题。然而，有两个基本问题限制了玻璃体内治疗的应用。许多药物会迅速从玻璃体液中清除；因此，为了达到并维持有效的治疗，需要重复注射。重复玻璃体内注射会增加眼内炎、晶状体损伤、视网膜脱离的风险。此外，一些药物在有效剂量下会引发局部毒性，导致副作用和可能的视网膜病变。在这种情况下，开发和使用用于玻璃体内给药的新型药物递送系统对于治疗慢性眼部疾病是必要的。其中，脂质体等微粒系统已得到广泛研究。脂质体易于注射，能够降低毒性并延长几种药物在眼内的停留时间。它们还能够保护体内稳定性差的分子（如肽和核酸）不被降解。在治疗人类巨细胞病毒引起的视网膜炎以及最近治疗动物葡萄膜炎方面已取得了一些有前景的结果。最后，脂质体注射到玻璃体后在眼组织和体液中的命运及其清除途径开始为人所知。
