Expanding our vision for steroid implants

How appropriate is the long-term intravitreal steroid technique in the modern clinic.

Innovations in retinal treatments have given modern clinicians access to 3 injectable implants or intraocular use: the dexamethasone intraocular implant 0.7 mg (Ozurdex; Allergan), the fluocinolone acetonide intravitreal implant 0.19 mg (Iluvien, Almera Sciences), and acetalone. 0.18 mg intravitreal implant (Yutiq; EyePoint Pharmaceuticals).

Dexamethasone intravitreal implant 0.7 mg, which has an effect duration of about 3 to 6 months, is indicated for diabetic macular edema (DME), macular edema after subretinal vein occlusion (RVO) or central RVO, and noninfectious uveitis affecting the posterior segment.1

Fluocinolone acetonide intravitreal implant 0.19 mg is indicated for DME,2 Fluocinolone acetonide intravitreal implant 0.18 mg is indicated for non-infectious chronic uveitis affecting the posterior segment; Each of these implants is biodegradable and designed to release medication for approximately 36 months.3

I have benefited from all three steroid implants in my clinical practice. Typically, these implants are used strictly for the indicated disease states (eg, intravitreal implants fluocinolone acetonide 0.19 mg for the treatment of DME). In other cases, I have found that a comprehensive understanding of disease indicators warrants the use of a specific agent.

For example, the use of steroid implants in patients with chronic postoperative posterior segmentitis and/or cystic macular edema that have not responded to treatment with topical anti-inflammatory drugs/corticosteroids is within the intravitreal implant limits of dexamethasone 0.7 mg and intravitreal fluocinolone acetonide. Implant 0.18 mg are indications of uveitis, and may require us to set aside our assumption that these agents are prescribed only for more traditional presentations of uveitis.

Furthermore, given the robust data sets from clinical trials that have evaluated the safety and efficacy of these implants, we can proceed with treatment armed with knowledge of the range of potential disease responses.

Of these three, the fluocinolone acetonide intravitreal 0.18 mg implant has recently received regulatory approval, and we are learning more about its practical applications. With this in mind, I would like to share two real-world examples of its use in uveitis patients who have had cataract surgery.

Case #1:

Chronic bilateral undifferentiated uveitis

A 27-year-old white female patient with a medical history of drug-induced lupus presented to the clinic with blurry vision and bilateral floaters who had been on and off for several years. The patient had previously been treated with a combination of topical and oral steroids, systemic immunosuppression, and multiple dexamethasone administrations.

On examination, the patient’s best visual acuity (BCVA) was determined to be 20/70 OD and 20/50 OS, with intraocular pressure (IOP) measurements of 16 and 18 mm Hg, respectively. Although her anterior chamber was deep and quiescent, vitreous cells were measured at 2+ in each eye, with vitreous haze at 1+ OD and 2+ OS. Bilateral epiretinal membranes (ERM) including the macula are also observed. Laboratory operations were unremarkable.

After evaluating the results of fluorescein angiography and optical coherence tomography (OCT) (Figures 1 and 2), I diagnosed this patient with bipolar Irritable Bowel Syndrome. The patient chose to discontinue systemic immunosuppression, citing multiple infections that had arisen during treatment and required hospitalization. Given that her disease had responded well to previous intravitreal corticosteroid injections, we determined that an intravitreal fluocinolone acetonide 0.18 mg implant was an appropriate treatment.

The patient adhered to a follow-up regimen similar to that described in the sidebar, ‘Follow-up regimens after implant administration’. At 6 months, BCVA improved to 20/25 OD and 20/20 OS, and IOP measurements were 14 and 17 mm Hg, respectively. The patient’s anterior chambers remained deep and quiet, with no observable vitreous cells or vitreous haze. The patient’s bilateral ERM was still present. OCT imaging accurately depicts edema (Figure 3). The patient has since undergone bilateral cataract extraction with IOL placement, and will continue to be monitored.

Case #2:

Unilateral undifferentiated pars planetesi

An Asian woman in her mid-30s presented to the clinic with a history of unilateral undifferentiated peritonitis in her left eye. Although her general medical history has been unremarkable, she has a history of blurry vision operating system that was treated with a series of periocular and intravitreal injections of triamcinolone prior to her inception for care with me. Her blurry vision was not associated with any known retinal vascular problems, and no history of vitreous haze was reported, although documentation of her treatment history was rather scanty. She was referred to my clinic a month after she underwent uncomplicated cataract surgery in the affected eye.

The patient did not respond well to previously prescribed oral steroids for uveitis. Uveitis occurred 4 months after her initial appointment, and her visual acuity (as usually during recurrence of uveitis) decreased to about 20/40 (Figure 4); A large glass fog was observed at this time. I administered dexamethasone intravitreal implant 0.7 mg, visual acuity returned to approximately 20/20 and visual symptoms resolved. Uveitis recurred after 6 months, with visual acuity reduced to 20/70. Another intravitreal implant received dexamethasone 0.7 mg and responded similarly to the first administration.

Given the positive disease response to the steroid implant, the patient was selected to administer the implant intravitreal long-acting fluocinolone acetonide 0.18 mg. She received the implant a year after her initial submission. In the nearly 2.5 years since receiving the transplant, uveitis has remained under control (Figure 5). No IOP problems were detected while monitoring appointments.

patient selection

Not all patients are well suited for long-term steroid implants, especially if they remove the drug over several years. Perhaps unexpectedly, patients who find it difficult to attend follow-up appointments are poor candidates for a long-acting drug such as fluocinolone acetonide intravitreal implant 0.18 mg.

Although it may be tempting to consider fluocinolone 0.18 mg treatment for a patient with a poor follow-up record, allowing a continuous low dose of treatment regardless of their presence in the clinic, doing so may risk developing undetected and under-reported IOP-related complications treatment in its early stages. In this case, failure to adhere to follow-up may result in permanent vision loss.

Given this dynamic, I only use steroid implants in patients with proven follow-up patterns. The official label for intravitreal 0.18 mg fluocinolone acetonide includes a comprehensive list of contraindications.3

By the time patients with chronic inflammatory conditions arrive at our clinics, they are often frustrated, seeking targeted treatment and craving relief. In patients whose disease corresponds to the approved indications for steroid implantation, and whose history with steroids indicates a possible disease response, these treatments may provide consistent and long-term relief.

Brian K. Doe, MD
E: bdo@rgw.com
Do works in practice with the Retina Group of Washington in the Washington, D.C. area, and is a clinical assistant professor of ophthalmology at Georgetown University.
references
1. Ozordex. Package insert. Allergan. 2020.
2. Eluvian. Package insert. Alimera Sciences; 2016.
3. Yutiq. Package insert. EyePoint Pharmaceuticals; 2022.