April 02, 2025
Glaucoma is the leading cause of irreversible blindness with 80 million patients affected worldwide. Multidisciplinary specialists at Mayo Clinic work together to generate new knowledge through cutting-edge research and to translate discoveries into therapies to advance patient care.
"Through advanced technologies and extensive resources, we're committed to innovating research to better understand and treat glaucoma," says Arthur J. Sit, M.D., M.S., an ophthalmologist and researcher at Mayo Clinic in Rochester, Minnesota. "The collective goal is to connect patients with optimal treatment options and improve overall outcomes."
Therapies for glaucoma are primarily directed toward reducing intraocular pressure (IOP), which is the leading risk factor and only reliable therapeutic target. "However, most patients with elevated eye pressure do not get glaucoma, and up to half of people with glaucoma get the disease despite having typical eye pressure," says Gavin W. Roddy, M.D., Ph.D., an ophthalmologist and researcher at Mayo Clinic in Rochester, Minnesota. "Our team focuses on developing better treatment options for reducing pressure but also understanding the reasons for this paradox and identifying new options for treatment beyond lowering pressure."
Recent research highlights include:
Transgene expression of stanniocalcin-1 provides sustained intraocular pressure reduction by increasing outflow facility
PLOS One, May 2022
Although topical therapeutics are typically first-line treatments for patients with glaucoma, less than 50% of patients take drops as prescribed. Sustained release technologies that decrease IOP for extended periods of time are being examined for clinical use.
Stanniocalcin-1 was recently identified as an IOP-lowering agent. This research shows that a single injection into the anterior chamber of mice with an adeno-associated viral vector containing the transgene of stanniocalcin-1 results in diffuse and sustained expression of the protein and produces IOP reduction for up to six months.
As the treatment effect begins to wane, repeat injections have shown success in lowering IOP. Aqueous humor dynamic studies revealed an increase in outflow facility as the mechanism of action. This therapeutic approach has the potential to improve care and reduce the rates of vision loss in those affected by glaucoma.
Subconjunctival administration of an adeno-associated virus expressing stanniocalcin-1 provides sustained intraocular pressure reduction in mice
Ophthalmology Science, July 2024
This research investigated subconjunctival administration of a single-stranded, adeno-associated virus, serotype 2, engineered to express stanniocalcin-1 with a FLAG tag (ssAAV2-STC-1-FLAG) as a novel sustained IOP-lowering agent with a reduced ocular surface side effect profile.
Subconjunctival delivery of ssAAV2-STC-1-FLAG significantly reduced IOP for 10 weeks postinjection in normotensive mice. Maximal IOP reduction was seen at week 3 postinjection. After the IOP-lowering effect had waned, a second injection restored the ocular hypotensive effect.
Subconjunctival delivery of the STC-1 transgene with a vector system may represent a novel treatment strategy for sustained IOP reduction and improved ocular tolerability. This also avoids the daily dosing requirements of currently available medications and the need for an injection inside the eye.
The effect of scleral buckle surgery on tonographic outflow facility, positional intraocular pressure, and ocular biomechanics
Ophthalmology Glaucoma, July 2023
This research investigated the in vivo effect of scleral buckle surgery on ocular biomechanics and aqueous humor dynamics. Participants included nine patients with unilateral 360-degree encircling scleral buckles without vitrectomy for rhegmatogenous retinal detachments, between three and 39 months postoperative.
Seated IOP was similar between buckled and nonbuckled eyes, whereas supine IOP was lower in buckled eyes compared with nonbuckled eyes. The percentage increase in IOP upon change in body position from seated to supine was greater in nonbuckled eyes. Ocular rigidity coefficient was lower in buckled as opposed to nonbuckled eyes. Outflow facility was not significantly different in buckled and nonbuckled eyes.
This research found that scleral buckling decreases ocular rigidity, but it does not affect outflow facility. This change in ocular biomechanics likely results in the attenuated IOP change from seated to supine position. Decreased ocular rigidity may also reduce IOP fluctuations and can potentially reduce the risk for glaucoma progression.
For more information
Roddy GW, et al. Transgene expression of stanniocalcin-1 provides sustained intraocular pressure reduction by increasing outflow facility. PLOS One. 2022;17:e0269261.
Roddy GW, et al. Subconjunctival administration of an adeno-associated virus expressing stanniocalcin-1 provides sustained intraocular pressure reduction in mice. Ophthalmology Science. 2024;5:100590.
Lyons LJ, et al. The effect of scleral buckle surgery on tonographic outflow facility, positional intraocular pressure, and ocular biomechanics. Ophthalmology Glaucoma. 2024;7:1.
Refer a patient to Mayo Clinic.