Eyeworld

80 | EYEWORLD | SPRING 2025 C ORNEA Contact Cheung: ACheung@cvphealth.com Shukla: rajan@brightstartx.com Tauber: jtauber@brightstartx.com Relevant disclosures Cheung: Brightstar Therapeutics Shukla: Brightstar Therapeutics Tauber: Brightstar Therapeutics delivered to the surgeon as a modified, decel- lularized, pre-stripped, pre-stained, and pre- stamped Descemet's membrane that is partially attached to its donor cornea. The donor corneal button is punched to size and placed on the dried anterior surface of the patient's cornea. The interface fluid is wicked away for 1–2 minutes. Afterward, the anterior stromal button is removed, and the Descemet's membrane (BrightMEM) is left behind. This is smoothed out and allowed to dry. If there are folds or wrinkles, adding a small amount of balanced salt solution will allow those to flatten. The physician then squeegees the interface fluid out to completely smooth the BrightMEM on the corneal surface. Fibrin glue is applied to seal the edges, and a bandage contact lens is placed over the eye. The entire procedure takes 15–20 minutes and can be performed under topical or block anesthesia, Dr. Cheung said. Dr. Tauber said the procedure is easy to learn. Most surgeons know how to perform a su- perficial keratectomy, to remove scar and vessels in order to expose a bare surface for BrightMEM placement. If there's a new thing for surgeons to learn, Dr. Tauber said it's the maneuvers to straighten and flatten the tissue because it's so thin (15 microns). It wrinkles easily, and it doesn't take much of a touch to produce another wrinkle. There are some specific maneuvers to get it to lay down flat, but if you do a typical case with- out a lot of scarring, it's a 15-minute case under topical anesthesia. More extensive scarring can lengthen the case significantly. Dr. Cheung said the main indication has been to heal persistent epithelial defects from a variety of etiologies. It is also currently being studied in cases of partial limbal stem cell defi- ciency, and Dr. Hou originally developed it with partial stem cell deficiency in mind. Dr. Tauber said that the labels characterizing superficial corneal disease get a bit confusing and many patients who fall under these indications have overlapping pathology with other epithelial diseases, so there may be other corneal con- ditions that can benefit from BrightMEM. For example, Dr. Tauber said many patients who have received BrightMEM had persistent epithe- lial defects and ocular pain from partial limbal stem cell deficiency but also had some degree of neurotrophic keratitis. As such, surgeons may find it helpful in a variety of ocular surface disease patients. However, Dr. Tauber cautioned physicians looking to use BrightMEM should take care to avoid cases with 100% stem cell deficiency, particularly as their first cases. Dr. Cheung said BrightMEM offers the benefit of improving epithelialization by giving epithelium a substrate to grow over. This could be compared to using amniotic membrane as an onlay, however, amniotic membrane doesn't last as long, and it is relatively opaque. Mr. Shukla said BrightMEM is commercially available. As of late 2024, around 60 surgeons have used BrightMEM. "We expect this to grow substantially through 2025," he said. Discussing some of the clinical data so far, Dr. Tauber said there has been data accumulat- ed on about 85 cases. "We're seeing about 90% fully healed at a mean of 32 days with a graft retention rate over 90%. Durability has been excellent, with 91% still healed at 6 months and 100% at 12 months. Healing rates vary some- what, depending on the subgroup," Dr. Tauber said, again stressing that it's important for surgeons to pick appropriate cases. BrightMEM can also be an adjunctive treatment used in combination, Dr. Tauber said. If you put down the ideal substrate, and you were to flood the surface with serum tears full of growth factors, that's a good combination for patients who have very few stem cells. If you add stem cells, that's even better. "I see collabo- ration as the future with what we're doing. This is not necessarily a standalone procedure," he said. Dr. Tauber said this is a new and different concept for treating ocular surface disease. It adds a different mechanism for improving corneal epithelial health that is separate from current therapies that focus mainly on improv- ing the tear film and lubricating the cornea. "We have many anti-inflammatories and aqueous or water substitutes [for tears]. We also have a kind of lipid substitute, something to prevent evaporation [of tears]." Now, with BrightMEM, there is a substrate to promote the healing of the epithelium. "I think the new frontier is growth factor supplementation," he said, adding that a number of companies are also exploring this space. continued from page 79

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