New Frontiers in Intravesical Therapies and Drug Delivery

Abstract

e u r o p e a n u r o l o g y 5 0 ( 2 0 0 6 ) 1 1 8 3 -1 1 9 3 a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . e u r o p e a n u r o l o g y . c o m Article info AbstractObjectives: The intravesical route permits site-specific delivery of drugs with a reduced side-effect profile as compared to oral delivery systems, either by avoiding first-pass metabolism or by obtaining a local effect. We investigated mechanisms related to urothelium permeability and new physical and chemical developments in intravesical drug delivery that potentially permit successful treatment of several bladder dysfunction. Methods: A literature review. Results: Pharmacologic agents increasing urothelial permeability and useful for clinical purposes have been described, such as dimethylsulfoxide, protamine sulphate, chitosan, and nystatin. Among physical approaches, electromotive drug administration appears to be more effective than intravesical passive diffusion in delivering drugs through the urothelium into deeper layers of the bladder. Experimental and clinical reports demonstrated that electric current significantly increases the transport of local anaesthetics, mytomicin C, oxybutynin, resiniferatoxin, epinephrine, and dexamethasone. Among new chemical approaches, cell-penetrating peptides posses the ability to translocate macromolecular drugs across membranes of urothelial cells. The therapeutic benefits of sustained delivery afforded by thermosensitive hydrogel, which forms a depot for hydrophilic and hydrophobic drugs, have been demonstrated by delivering anti-inflammatory drugs. Liposomes improve the aqueous solubility of several hydrophobic drugs such as taxol, amphotericin, and capsaicin. Conclusions: Electromotive drug administration, new in situ delivery systems, and bioadhesive liposomes may make it possible to extend intravesical therapy and drug administration to many bladder diseases. Research to expand knowledge of the chemical and physical properties of the bladder and processes regulating drug transport across biologic membranes is needed to make this a reality.

Intravesical delivery of 5‐aminolevulinic acid from water‐in‐oil nano/submicron‐emulsion systems

“…In addition, the acidic pH increases the ion permeability of the urothelium. 3 The release rate generally showed a trend of E3 > E1 > E4 > E2. The release kinetics of the Higuchi model assume that when one layer of w/o emulsion droplets is depleted of drug, release from the next layer begins.…”

“…2 The intravesical route permits site-specific delivery of drugs, with a reduced side-effect profile compared to oral delivery systems, either by avoiding first-pass metabolism or by obtaining a local effect. 3 Intravesical delivery is an administration method of inserting a catheter from the urinary tract to the bladder cavity to deliver drugs. 5-Aminolevulinic acid (ALA) is a precursor of protoporphyrin IX (PpIX), which is used in photodiagnosis and photodynamic therapies (PDT) of malignant bladder cancer.…”

Permeation Enhancer-Containing Water-In-Oil Nanoemulsions as Carriers for Intravesical Cisplatin Delivery

“…Permeation enhancers, such as α-terpineol and oleic acid, were also loaded in the nanoemulsions, since the chemical enhancers can increase the permeability of drugs through the urothelium (13). Thus, the anti-cancer activity of cisplatin can be enhanced via the encapsulation into the nanoemulsions.…”

Desenvolvimento e validação de método analítico espectrofotométrico para quantificação de nerolidol em um dispositivo polimérico de liberação prolongada, após derivatização com vanilina

“…[12][13][14] Nosso grupo de pesquisa desenvolveu formulações na forma de filmes, utilizando a quitosana como…”

“…11 É um polímero atóxico, biocompatível e biodegradável, características desejáveis e necessárias para veiculação de fármacos, sendo utilizada em diversas formulações farmacêuticas como pós, comprimidos, emulsões e géis, além de ser utilizado em imobilizações enzimáticas. [12][13][14] Nosso grupo de pesquisa desenvolveu formulações na forma de filmes, utilizando a quitosana como…”