27 EyeWorld Asia-Pacific | March 2025 REFRACTIVE SURGERY said, have allowed earlier and more accurate diagnosis of keratoconus, which is important to identify and treat early to stop progression and prevent subsequent, irreversible vision loss. Dr. Beckman also said epithelial mapping has been helpful in differentiating thickened epithelium from a steep cornea. Tracking progression of keratoconus has now become critical, as documented progression is indicated for use with the currently approved crosslinking system. Dr. Beckman said it’s also important to consider risk for progression. If you’re seeing a young patient who already has a significant cone, waiting to document progression could result in increased vision loss that could be prevented. He said these cases will often make it through insurance approval with an appeal. William Trattler, MD, said one of the major hurdles that came about after FDA approval of crosslinking was a change in mindset. Referring optometrists and comprehensive ophthalmologists had to be educated on careful monitoring of keratoconus and quick referrals for crosslinking. “Our goal has always been to diagnose early to identify patients because if we treat them early we can prevent more significant vision loss,” Dr. Trattler said. “If they are more advanced, we can still treat them so they don’t get hydrops or more serious complications and need a transplant. It’s really been a tremendous technology shift, and I think … the sooner that we can catch patients, the sooner we can treat them, the less morbidity will occur.” In addition, Dr. Trattler said that understanding of who can/should be crosslinked has evolved. “Patients with thin corneas and steep corneas can achieve successful strengthening of their corneas with crosslinking. In the past, there were some theoretical worries about corneas being too thin to undergo crosslinking, but studies have demonstrated that the patients with very thin corneas (even under 300 microns) can safely undergo crosslinking. For example, the sub400 protocol by Farhad Hafezi, MD, has demonstrated that reducing the time for UV light exposure can safely and effectively allow for crosslinking to be performed in corneas in the 200 to 400 micron range,1” he said. Dr. Rubinfeld added that patients over 30, 40, 50, and even 60 can rapidly progress despite information in old textbooks. He emphasized the need for continued monitoring even into older age. Blue light slit lamp photo of a human eye after 10 minutes of loading through intact epithelium using novel, patented Epion innovations; the epithelium is blue (no visible riboflavin in epithelium), and the stroma has a high concentration of riboflavin (very green). Source: Roy Rubinfeld, MD Next Up: Transepithelial In the U.S., transepithelial crosslinking protocols are in clinical trials. “Doctors have been interested in FDA-approved transepithelial crosslinking for a long time because it has the potential to be a faster procedure that may be more comfortable for patients,” said Brandon Ayres, MD, who was involved in Glaukos’ trials. “Without the need for epithelial removal, we might expect more rapid posttreatment healing and visual recovery and a reduction in the already low risk of complications from a less invasive procedure. However, we don’t want these benefits to come at the cost of efficacy of the procedure, so I think we all have been awaiting the results of ongoing clinical trials with both caution and optimism.” In October 2024, Glaukos reported positive topline results from its second, confirmatory Phase 3 pivotal trial for Epioxa, a system that uses a novel riboflavin formulation, a pulsed, higher-intensity UV-A irradiation protocol, and supplemental oxygen. This trial enrolled 312 eyes. According to the company’s press release announcing topline results, Epioxa achieved its primary efficacy outcome, “demonstrating a Kmax treatment effect of –1.0 D determined as prospectively defined least square mean Kmax change from baseline in the Epioxa treated arm versus the sham/placebo-controlled arm at the month 12 study endpoint.” A New Drug Application is expected to be submitted to the FDA by the end of 2024. In its first Phase 3 clinical trial for Epioxa, the treatment resulted in a statistically significant 1 D or greater difference in Kmax from baseline to 6 months compared to the control group, demonstrating the ability to stop or reduce keratoconus progression. Epion Therapeutics completed a Phase 2 clinical trial, which enrolled 2,258 participants with corneal ectasia,
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