The Effects of 5-Fluorouracil on Ocular Tissues In Vitro and In Vivo after Controlled Release from a Multifunctional Implant

Abstract

5-FU had a broad therapeutic range, and the 5-FU implant showed only minor tissue reactions in conjunctiva at the surgical site. 5-FU is a possible candidate for controlled drug release.

The Diagnostic and Therapeutic Challenges of Posttraumatic Iris Implantation Cysts: Illustrative Case Presentations and a Review of the Literature

“…5-FU is a pyrimidine-analog antimetabolite commonly used in glaucoma filtering surgeries and bleb revisions, dacryocystorhinostomy procedures, pterygium surgeries, conjunctival neoplasias, and vitreoretinal surgery, due to its antiproliferative and antiscarring properties [ 52 , 53 ]. Recently, there have been several reports exhibiting the use of 5-FU for successful treatment of diffuse epithelial downgrowth [ 54 – 57 ] but use of this medication in the management of iris implantation cysts has not been previously reported.…”

Delivery of therapeutics for deep-seated ocular conditions – status quo

“…[35] Ocular implants can also prolong therapeutic duration at the site of action compared to other conventional drug delivery methods such as eye drops. [36] The use of ocular implants can overcome the limitation of topical eye drops where drug wastage is an immediate issue. [36] Ocular implants allow the drug to reside at the site of action without having to deliver a large dose over a long period of time.…”

“…[36] The use of ocular implants can overcome the limitation of topical eye drops where drug wastage is an immediate issue. [36] Ocular implants allow the drug to reside at the site of action without having to deliver a large dose over a long period of time. [37] Despite these many benefits, the intravitreal administration of ocular implants does have major drawbacks, some of which include inconveniencing patients in terms of administration, risk of tissue damage and severe but rare adverse reactions such as endophthalmitis and haemorrhage.…”

“…In situ gels are a drug delivery system which when administered in a liquid form phase shift into a gel or solid form once reaching the conjunctival cul-de-sac. [39] Despite typically being administered [1,4] ) 2 Ability to modify the rate of release of drug [1,4] 3 Ability to provide a stimuli-sensitive drug release mechanism [1,4] 1 Allow sustained release of drug [35,36] 2 Prolonged therapeutic duration at site of action [35,36] 3 Can overcome limitation of eye drops where drug wastage is an issue [35,36] 1 No blurred vision or irritation with administration [39,40] 2 Prolonged drug retention at desired tissue in the eye [39,41] 3 Decreased frequency of dosing [40,41] 1 Both hydrophilic or lipophilic drugs can be used [32] 2 Increase drug penetration across conjunctival and corneal epithelium [32] 3 Display ability to provide sustained released [32,46] 4 Decreased frequency of dosing [46] Cons 1 Low reproducibility [4,48] 2 Instability of the macromolecules during production stage [4,48] 3 Variable size distribution [4,48] 4 Expensive [4,48] 1 May increase intraocular pressure and induce local systemic adverse effects [38] 2 Inconvenient administration for patient [38] 3 Risk of tissue damage if administered incorrectly [38] 1 Lack of cell specificity [41] 2 Requires intravitreal administration due to poor penetration & specificity [40] 3 Expensive …”

Studies on the release behavior of drugs in hyaluronic acid-nano/micro carrier composite hydrogels

“…Several polymeric (synthetic and natural) carriers have been used for delivery of 5Fu, mostly for therapeutic applications against different types of cancer [129]. 5Fu has also been investigated for ocular delivery applications [132,[139][140][141]. Among them, a couple of studies have focused on composite hydrogels using 5Fu loaded nanocarriers for ocular delivery.…”