Tag: Pharmaceutical drug

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Macular Degeneration Retina

Intraocular Drug Delivery – It's About Timing

Ok, maybe a little pun in the title.

Yesterday, I wrote about Alimera’s study using Iluvien™ for the treatment of diabetic macular edema.  As we have been commonly using intraocular steroid injections to treat this condition (see previous posts under “treatments”), it only makes sense that there are now products (Ozurdex/Allergan and Iluvien/Alimera) that have been designed for long-term release of steroids when injected into the eye.

Ten years ago, the notion of injecting medicines directly into the eye on a regular basis were somewhat far-reaching.  There were some treatments for AIDS eye disease (CMV retinitis) that required repeated and frequent eye injections, but the risks (of the injections) were low.  There was no other therapy.  Intravenous and oral medications just didn’t work.  If no shot were given, then the patient could go blind….in a matter of a few weeks.  (As a matter of fact, an intraocular device did become available for continuous release, but there were significant drawbacks.)

The “timing” is perfect for these injectable intraocular drug delivery systems. Intravitreal injections are now common place.  There is no more hesitation.  These eye injections are routinely given in a retina specialists office.  The injections use very thin needles.  Since the insertion site is so small, surgery is avoided as these entry sites seal by themselves.  We have discussed the merits of intraocular injections before; Lucentis®, Macugen®, Avastin®, and steroids.

The “timing” is perfect for sustained release intraocular drug delivery systems. In cases of macular degeneration, the treatments need to be repeated and can be as frequent as once a month.  These monthly injections may need to be given for over a year.

Wouldn’t it be great if we could………..some day, have sustained intraocular drug delivery systems that were releasing anti-macular degeneration drugs?  Actually, that day may be just around the corner.

“Randy”

Randall V. Wong, M.D.
www.TotalRetina.com
Ophthalmologist, Retina Specialist

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Diabetic retinopathy Treatments

Company Hopes Injectable Implant Cures Diabetic Macular Edema

Alimera Sciences hopes that its Iluvien ™ insert will be effective against diabetic macular edema.  Iluvien™ will release a steroid called fluocinalone acetonide (FA) after insertion into the eye.  The Iluvien™ system will deliver the steroid for up to 3 years.  It is anticipated that intraocular steroid release may control macular edema and improve vision.  The company has a study underway to determine just how effective this intraocular, sustained release drug system for the treatment of diabetic macular edema can be.

Alimera Sciences’ web site.

Is this new? Well, yes and no.  The technology is new.  A small implant will be injected into the eye.  The device will release a small amount of steroid into the vitreous for up to 36 months.  The injection site will be very small and will not require any stitches to close.  The entry point will be so small that it will self-seal.

“Old Drug – New Tricks” The drug, fluocinolone acetonide (FA), is not new.  It is an old, well studied, steroid.  Topical steroid drops, oral steroids and even intravenous steroids (IV) do not get into the eye very easily.  In order to get enough drug into the eye via these methods, the doses required become quite high, thereby increasing the likelihood of systemic toxicity.  Ideally, the direct insertion of the drug to its target tissue (the retina) will be more effective in treating macular swelling due to diabetic retinpathy (aka diabetic macular edema) than present treatments.  To state another way, by simply changing the route by which a drug is delivered (in this case directly into the eye versus, say, eye drops), the drug becomes more effective.

This is not really new news. If you have been reading carefully over the past year, steroids have been very useful for the treatment of macular swelling, not only in patients with diabetes, but also in cases of macular degeneration, retinal vein occlusions, etc.  Intraocular injections of steroids, such as triamcinalone acetonide (TA), have been widely used by retinal surgeons for the past 5 – 10 years, but they often need to be repeated.  A sustained release delivery system is needed (give an injection once, and it lasts for years).  So, using steroids to treat retinal swelling just makes sense.

Ozurdex® received FDA approval in June 2009. Allergan, Inc., just released its new steroid releasing implant.  Ozurdex® is an injectable sustained release system that was FDA approved in June of this year.  It is now available for patient use.  Ozurdex® also releases steroid inside the eye for up to 6 months.  The system then safely dissolves.  This system was FDA approved for the treatment of retinal swelling (aka macular edema) caused by retinal vein occlusions.  I predict that it will soon be used, off-label, for the treatment of diabetic macular edema.  Read my previous post regarding Ozurdex®.

This is all good news. To date, the Ozurdex® and Iluvien™ implants both validate the effectiveness of intraocular steroids for the treatment of diabetic macular edema.  Both are intravitreal, long term release systems.  They are small and can be delivered safely in an office.  It is exciting that new treatments, using well-studied medicines, are now available for treating such a prevalent complication of diabetic retinopathy.

Lastly, the advantages of sustained released systems can not be understated.  While it may sound a little aggressive to be injecting medicine directly into the eye, it is proving to be very effective in treating many eye diseases such as macular degeneration.

Intraocular injections have two major advantages, it delivers drug right where you want it and it takes lower doses than otherwise would be needed if given orally or by intravenous.  Therefore, little chance of side effects to the rest of the body!  The drug works at lower levels because it is injected right where it is needed.  It also may reduce the number of office visits (i.e. costs) and also increases “compliance,” that is, there is no question the patient is taking his/her “medicine.”

“Randy”

Randall V. Wong, M.D.
www.TotalRetina.com
Ophthalmologist, Retina Specialist

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Categories
Diabetic retinopathy Treatments

Steroid Implant May Reduce Diabetic Retinal Edema

In June, the FDA approved a new intraocular device for the treatment of so-called retinal vein occlusions. In this disease, the whole or partial venous tree of the retina becomes occluded. Secondary swelling of the macula occurs thereby reducing vision. Current therapy involves only laser treatment.

This new drug delivery system, marketed by Allergan Pharmaceuticals, will be available later this year.  It will involve an in-office injection of the small device right into the eye.  Dexamethasone, a well studied steroid, will be released for about 6-9 months.  The system, itself, will biodegrade as the drug is released.

The Ozurdex® system was noted to improve vision in up to 30% of patients suffering from RVO.

What does this have to do with diabetic retinopathy? There has been evidence over the past few years that direct injection of steroids was beneficial to patients with RVO.  Similarly, there is evidence that steroids also may improve diabetic macular edema AND age related macular degeneration.  Doctors, like myself, have been injecting steroids for these entities for several years, using the medications “off-label.”  Don’t worry, using medications off-label is legit.  In the end, this steroid implant may be a very useful tool to combating macular edema in diabetics!  It is just around the corner!

Randy

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist

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