Q&A: Matthew Starr, MD, shares insights into RHONE-X trial

Photo of Matthew Starr, MD, taken at Retina World Congress 2025

Matthew Star, MD, assistant professor of ophthalmology and the Program Director of the residence program at the Mayo Clinic, discusses the RHONE-X trial. RHONE-X is a long-term, multicentered, open-label extension trial of both the YOSEMITE and RHINE trials. It evaluated the use of a treat-and-extend dosing regimen of faricimab for the treatment of diabetic macular edema (DME).

Note: This conversation has been lightly edited for clarity.

Ophthalmology Times: Can you share about the RHONE-X trial, which you are presenting on at this 2025 Retina World Congress meeting in Fort Lauderdale, Florida?

Matthew Starr, MD: I'm talking about the RHONE-X trial, which is a long-term, multi-centered, open-label extension trial of the YOSEMITE and RHINE trials, where patients were examined using a treat-and-extend dosing regimen of faricimab for diabetic macular edema. It is the first 4-year study of treat-and-extend dosing for patients receiving faricimab for diabetic macular edema. The highlights of that study showed that patients who received faricimab had a treat-and-extend dosing interval had maintained vision and central subfield thickness improvements that were seen in YOSEMITE and RHINE up to 4 years with a significantly fewer number of injections. The median number of faricimab injections in year 4 for all patients was only 3. So really, the take home message is that using a treat-and-extend dosing with faricimab for patients with diabetic macular edema, many patients are able to extend it out to 12 weeks, 16 weeks, and still maintain vision and CST improvements over time.

OT: As we talk about those improvements in vision, what gains were observed?

Starr: Patients in YOSEMITE and RHINE saw about a 10-letter gain at the end of those study periods, and by the end of RHONE-X, the same letter gain was achieved. All patients had about a 10-letter gain at the end of RHONE-X, irregardless of the treatment arm in YOSEMITE and RHINE, whether it was Q8 week aflibercept, Q8 week faricimab, or the treat-and-extend faricimab from the beginning. And so once those patients were then transitioned from those treatment arms into a treat-and-extend regiment, they still maintained those 10-letter vision gains from baseline with about about a 200 micron reduction in CST from baseline as well.

OT: What are the plans for the future of RHONE-X or the resulting dataset taht we have from this trial?

Starr: RHONE-X is done enrolling, but they're always going to be other ad-hoc analyzes that are going to be performed using this data set. It's a very rich data set, almost 1,500 eyes enrolled, and about 1,200 completed it. So it has an 82% retention rate. Again, it's a very rich data set, but RHONE-X is no longer enrolling, so it'd be more ad-hoc analyzes at this point.

OT: With this data in mind, as you look toward the future of ophthalmology, where do you think the field is headed?

Starr: Yeah, specifically in this arm, it's all about durability and reduction in treatment burden. We have good treatments, but how can we make them better and more durable for our patients, so they don't have to keep coming to the office or keep coming in to clinic, things like that. And so this is your first step in reducing that injection burden, reducing that treatment burden, while maintaining your good vision and anatomic outcomes.