The U.S.-based, federally funded DRCR Retina Network recently invited Texas Retina’s Michel J. Shami, MD, to provide investigators with updates on three of the network’s current studies:

  • Protocol AF: A randomized trial evaluating fenofibrate for prevention of diabetic retinopathy worsening.
  • Protocol AM: Immediate vs. deferred surgery for symptomatic epiretinal membranes.
  • Protocol AL: Faricimab or iluvien vs. observation for the prevention of visual acuity loss due to radiation retinopathy.

Originally established more than two decades ago, the DRCR Retina Network conducts large-scale clinical trials and studies on diabetic retinopathy, diabetic macular edema, and other major retinal diseases. Its mission is to advance the understanding and treatment of retinal conditions and improve patient outcomes.

Dr. Shami, who practices at Texas Retina’s Lubbock office, is one of the network’s original investigators. Over the years, he has successfully enrolled 126 participants in 29 different DRCR protocols.

Evaluating a Potential Approach to Prevent Diabetic Retinopathy – Protocol AF

In diabetic retinopathy, high blood sugar levels can damage the blood vessels in the retina. These vessels may swell or leak, or they may become blocked, preventing adequate blood flow. In some cases, abnormal blood vessels can grow on the retina. All these changes can lead to vision loss.

Fenofibrate, the medication being tested in DRCR Protocol AF, is used to treat high triglycerides and certain types of high cholesterol. Researchers believe it may also help protect small blood vessels in the eyes through direct cellular and molecular effects.

The AF study is fully enrolled, and participants will be followed for four to six years.

“Given the projected number of people with diabetes over the next 10 years and the fact that diabetic retinopathy remains a leading cause of blindness, the AF study has enormous public health implications both in and outside the U.S.,” shared Dr. Shami. “I believe this protocol carries the same importance as AREDS2, a landmark clinical trial sponsored by the National Eye Institute that resulted in a widely used blend of dietary vitamins and minerals shown to slow the progression of age-related macular degeneration (AMD) from intermediate to advanced, vision-threatening stages.”

Examining Surgical Timing for Symptomatic Epiretinal Membranes – Protocol AM

An epiretinal membrane is a thin layer of scar tissue or fine membrane that forms on the inner surface of the retina, often over the macula, which is responsible for sharp, detailed central vision. In many cases, these membranes remain flat and do not cause noticeable vision problems. In others, the membrane can contract over the macula, causing the retina beneath it to wrinkle or pucker. This condition is also known as a macular pucker and can cause blurry or distorted vision.

When symptoms are mild, a macular pucker can often be observed and generally does not damage the underlying retina. For patients with more significant symptoms, the membrane can be removed surgically through a procedure called vitrectomy which involves carefully removing the vitreous gel that fills the back of the eye. Then the membrane is gently peeled from the surface of the macula using fine, microscopic instruments. The eye is subsequently filled with a saline solution, and the incisions are closed. After the membrane is removed, the retina can gradually return to its normal shape, and vision may improve over the following weeks.

The DRCR Protocol AM study is evaluating the impact of immediate versus deferred surgery for symptomatic epiretinal membranes. The study is currently enrolling, and researchers are specifically looking for patients with good visual acuity of 20/40-20/25.

Dr. Shami believes this research could help answer an important question about when surgery is most appropriate.

“At this point, we do not have good level 1 evidence to guide our patients regarding observation versus early intervention,” he said. “Hopefully, the AM study will answer that question.”

Preventing Vision Loss Due to Radiation Retinopathy — Protocol AL

Radiation retinopathy is a delayed, progressive condition that damages the blood vessels of the retina. It can develop months or even years after radiation therapy for eye tumors, brain tumors, or head and neck cancers. Symptoms may include blurred vision, blind spots and vision loss.

In Protocol AL, researchers are evaluating two medications versus observation to determine whether they can prevent vision loss associated with radiation retinopathy:

  • Faricimab (Vabysmo) is an anti-VEGF and anti-Ang-2 bispecific antibody injected into the eye. It targets two proteins involved in abnormal blood vessel growth and leakage in the retina.
  • Iluvien is a corticosteroid implant containing fluocinolone acetonide. Rather than targeting specific growth factors, it works by suppressing inflammation and reducing vascular leakage in the eye.

The AL study is still currently recruiting participants at Texas Retina Lubbock and other sites throughout the DRCR Retina Network.

Additional DRCR Studies at Texas Retina Lubbock

In addition to the three studies Dr. Shami presented, he currently serves as a Principal Investigator for two other DRCR clinical trials:

  • Protocol AO: Home OCT-guided treatment vs. treat-and-extend for the management of neovascular AMD. Dr. Shami is one of the network’s top individual recruiters for this study, which is now fully enrolled. Participants will be followed for three years.
  • Protocol AP: A randomized clinical trial evaluating combination faricimab + panretinal photocoagulation (PRP) vs. vitrectomy + endolaser for treatment of proliferative diabetic retinopathy. This study is currently enrolling patients, and the purpose is to determine whether an early surgical intervention for proliferative diabetic retinopathy would reduce risks of severe traction detachment and poor outcomes compared to standard treatment.

“Protocol AP arose from the concern that some patients are unable to comply with long-term anti-VEGF treatment or are lost to follow up and eventually suffer vision loss as a result,” explains Dr. Shami. “The hope is that early vitrectomy would stabilize those eyes and reduce negative outcomes.”

Dr. Shami is especially excited about the AO protocol and the potential for home OCT monitoring to inform treatment decisions.

“The AO protocol may revolutionize the way wet AMD patients are treated and followed since monitoring can be done from home,” he shares. “Traditional Medicare is now covering the SCANLY Home OCT from Notal Vision, and the device is FDA approved.”

He also remains committed to the DRCR Retina Network’s broader mission and its ongoing research efforts.

“You can see that a great deal of work is being conducted within the DRCR Network. Over the years, this has resulted in more than 100 peer-reviewed publications and helped to define better treatments for diabetic retinopathy and other retinal diseases. These well-conducted clinical trials are generating level 1 evidence that is improving outcomes for patients here in Texas and throughout the country.”

Learn More About DRCR Clinical Trials at Texas Retina Lubbock

For more information or to determine eligibility for currently enrolling DRCR protocols at Texas Retina Lubbock, contact study coordinator Angela Fuller, COA, at 806-792-0066 ext. 1811.

About the DRCR Retina Network

The DRCR Retina Network was founded in 2002 with support from the National Eye Institute (NEI), part of the National Institutes of Health (NIH). Originally known as the Diabetic Retinopathy Clinical Research Network, the organization expanded its focus beyond diabetes and was renamed the DRCR Retina Network in 2019.

Today, the network includes more than 140 clinical sites and more than 400 physicians across the United States and Canada, conducting collaborative clinical research designed to advance the prevention, diagnosis and treatment of retinal diseases.