MyVisionTest News Archive
Jan 27, 2010
Implant technologies poised to revolutionize drug delivery
Traditionally, ocular medications have been delivered through eye drops, intravitreal injections and systemic means. Now, various implants are being developed to deliver drugs for numerous indications.
The main impetus for drug-eluting devices, especially in glaucoma, is patient noncompliance with dosing protocols, Steven D. Vold, MD, said.
"Compliance is just a real challenge for patients,” Dr. Vold said. "If we could find a way to make it so patients don't have to put in drops on a regular basis, I think, no question, it would be one of the bigger breakthroughs in medical therapy."
Currently, two drug delivery devices are approved by the U.S. Food and Drug Administration for retina/vitreous disorders: Retisert (fluocinolone intravitreal implant) and Ozurdex (dexamethasone intravitreal implant). Retisert is approved for noninfectious posterior uveitis. Ozurdex is indicated for macular edema following central and branch retinal vein occlusion.
In glaucoma, implants in development include a punctal plug that delivers latanoprost from a drug-eluting core and a drug-eluting hydrogel contact lens.
Anterior surface implants in the pipeline include soft contact lenses, IOLs and a device attached to the haptics of an IOL. Currently, no drug-eluting contact lenses or IOLs have FDA approval.
Research is also focused on nanotechnologies that enable even more timely and targeted drug delivery.
In addition to Retisert and Ozurdex, Vitrasert, an implantable sustained release reservoir that contains ganciclovir for treatment of AIDS-related cytomegalovirus retinitis, is used infrequently. Vitrasert was introduced in the early 1990s.
The manufacturers of Retisert and Ozurdex have initiated clinical trials for additional indications, such as uveitis (Ozurdex) and macular edema secondary to diabetic retinopathy (both devices). There is also interest in some sectors in using implants in combination therapy for treatment of neovascular age-related macular degeneration.
Meanwhile, several other manufacturers are developing drug delivery devices and systems, including Alimera Sciences (Iluvien, fluocinolone acetonide); Lux Biosciences (LX212, voclosporin); Allergan (using the same platform as Ozurdex, but containing brimonidine tartrate for treatment of geographic atrophy due to AMD); and Neurotech (encapsulated cell technology employing ciliary neurotrophic factor, which may have applications in dry AMD, geographic atrophy and retinitis pigmentosa).
SurModics Pharmaceuticals is developing a number of drug delivery devices, most notably the I-vation implant (triamcinolone acetonide), and Replenish is developing a reservoir that could deliver a wide range of agents.
The advent of these devices portends a new way of treating patients, albeit tempered by cautious optimism.
"I think in the next 3 to 5 years, if we look back, we might see that we may not have wanted to do these implants, but if the results pan out and we are able to improve our patients' vision with less treatments and less side effects, I think you're really going to see people shift towards that," Dr. Shah said.
Read more...
OSN Supersite
Tags: drug delivery, AMD, retinal vein occlusion, macular edema
Traditionally, ocular medications have been delivered through eye drops, intravitreal injections and systemic means. Now, various implants are being developed to deliver drugs for numerous indications.The main impetus for drug-eluting devices, especially in glaucoma, is patient noncompliance with dosing protocols, Steven D. Vold, MD, said.
Currently, two drug delivery devices are approved by the U.S. Food and Drug Administration for retina/vitreous disorders: Retisert (fluocinolone intravitreal implant) and Ozurdex (dexamethasone intravitreal implant). Retisert is approved for noninfectious posterior uveitis. Ozurdex is indicated for macular edema following central and branch retinal vein occlusion.
In glaucoma, implants in development include a punctal plug that delivers latanoprost from a drug-eluting core and a drug-eluting hydrogel contact lens.
Anterior surface implants in the pipeline include soft contact lenses, IOLs and a device attached to the haptics of an IOL. Currently, no drug-eluting contact lenses or IOLs have FDA approval.
Research is also focused on nanotechnologies that enable even more timely and targeted drug delivery.
In addition to Retisert and Ozurdex, Vitrasert, an implantable sustained release reservoir that contains ganciclovir for treatment of AIDS-related cytomegalovirus retinitis, is used infrequently. Vitrasert was introduced in the early 1990s.
The manufacturers of Retisert and Ozurdex have initiated clinical trials for additional indications, such as uveitis (Ozurdex) and macular edema secondary to diabetic retinopathy (both devices). There is also interest in some sectors in using implants in combination therapy for treatment of neovascular age-related macular degeneration.
Meanwhile, several other manufacturers are developing drug delivery devices and systems, including Alimera Sciences (Iluvien, fluocinolone acetonide); Lux Biosciences (LX212, voclosporin); Allergan (using the same platform as Ozurdex, but containing brimonidine tartrate for treatment of geographic atrophy due to AMD); and Neurotech (encapsulated cell technology employing ciliary neurotrophic factor, which may have applications in dry AMD, geographic atrophy and retinitis pigmentosa).
SurModics Pharmaceuticals is developing a number of drug delivery devices, most notably the I-vation implant (triamcinolone acetonide), and Replenish is developing a reservoir that could deliver a wide range of agents.
The advent of these devices portends a new way of treating patients, albeit tempered by cautious optimism.
"I think in the next 3 to 5 years, if we look back, we might see that we may not have wanted to do these implants, but if the results pan out and we are able to improve our patients' vision with less treatments and less side effects, I think you're really going to see people shift towards that," Dr. Shah said.
Read more...
OSN Supersite
