Therapeutics

Advances in retinal therapy

The latest in treatments for retinal disorders, including AMD, diabetic retinopathy, DME, and macular edema

BY ANDREW MATHIS, PhD, CONTRIBUTING EDITOR

» Wet AMD treatments have undergone tremendous advances in the past decade.COURTESY OF MICHAEL COLUCCIELLO, MD

Over the last decade, retina subspecialty treatments have grown at a previously unimaginable rate. Diseases that once invariably resulted in permanent vision loss, such as age-related macular degeneration (AMD), are now not only treatable, but lost vision can actually be restored in many cases. The result of this unprecedented growth is that the subspecialty can be confusing for the ophthalmic professional.

What do you need to know about retinal disorders and treatments? The easiest way to provide the most recent developments in treatments is to discuss each of the most common disorders and conditions that retinal physicians treat.

Age-related macular degeneration

AMD is the most common retinal disease among elderly people in the United States. There are early and advanced stages of the disease, with the early stage typically causing no symptoms.

The advanced stage has two forms: exudative (“wet”) and nonexudative (“dry”). The dry form of the disease remains untreatable. Treatments for the wet form, however, have undergone tremendous advances in the past decade.

The standard of care for wet AMD is the use of intravitreal injections of anti-VEGF drugs. While the first such drug widely used was bevacizumab (Avastin, Genentech), which is actually a drug with FDA approvals only for metastatic cancers, the related drug ranibizumab (Lucentis, Genentech), approved in 2006, has since proved very popular.

A newer drug, aflibercept (Eylea, Regeneron), was approved in 2012. Compared to ranibizumab, aflibercept boasts a longer interval between treatments than ranibizumab. However, so-called “treat and extend” protocols, with which doctors increase the interval as long as possible without compromising vision, are being used with increasing frequency with all anti-VEGF agents.

Diabetic eye diseases

The vision complications caused by diabetes are diabetic retinopathy (DR), which affects the small blood vessels in the eye with micro aneurysms, and diabetic macular edema (DME), a common consequence of DR in which fluid accumulates beneath the macula, which is the part of the retina that provides central vision.

Although laser continues to be the gold standard to treat both of these disorders, pharmaceutical interventions have received approvals in the last few years.

Both aflibercept and ranibizumab have FDA approvals to treat both DME and the DR that causes it. Also, because macular edema frequently accompanies retinal vein occlusion (RVO), both drugs are also approved for that condition.

In addition, given their frequent use in combination therapies for eye diseases, several steroid treatments, in the form of intravitreal implants, have received approval in recent years. Two steroids, dexamethasone and fluocinolone acetonide, are available in implant form for a variety of indications. The broadest use has been granted for Allergan’s dexamethasone implant (Ozurdex), with approvals for DME and RVO, as well as macular edema associated with non-infectious uveitis. The two fluocinolone implants, Bausch + Lomb’s Retisert and Alimera Sciences’ Iluvien, have approvals for edema as a result of uveitis and DME, respectively.

Finally, triamcinolone acetonide is another corticosteroid that ophthalmologists have used off-label for years to treat macular edema from myriad causes, including from DME. The therapy is normally a component of combination therapy. Like the steroid implant and anti-VEGF drugs, it is injected intravitreally; a preparation called Kenalog-40 (Bristol-Myers Squibb) has an on-label approval for ocular inflammatory diseases that have not responded to topical treatment, although macular edema remains an off-label use.

Ocriplasmin

Another drug approved recently, ocriplasmin (Jetrea, ThromboGenics), is used for vitreomacular adhesion. With this condition, the vitreous — the gel that forms the contents of most of the eye — adheres to the retina, which can distort vision and even cause retinal detachment. Ocriplasmin was approved in 2012, and the drug requires careful patient selection to maximize the results.

Conclusion

As time goes on, more drugs will likely be approved for these and other retinal disorders. We are fast approaching the day when retinal surgery could become exceedingly rare or even non-existent.

Learning about the drugs that retinal physicians will be using will provide the ophthalmic professional with a clear advantage. OP