Monday, May 9, 2016

OT-Luna’s Synthetic Bandages for the Treatment of Ocular Trauma to be presented at World Biomaterials Congress

Lauren Costella, Associate ScientistChristopher Tison, PhD, Team LeaderBiomedical Technologies Group

Ocular Injuries are Widespread and Inefficiently Treated

Up to two million people sustain ocular trauma that threatens to reduce or eliminate their vision each year. The likelihood of maintaining normal vision is directly related to immediate management of the injury. Having access to the appropriate ocular repair dressing, cleansing solutions and antibiotics is therefore critical for restoring function and minimizing tissue loss.
The current standard of care for ocular surface injuries includes the suturing of human amniotic membrane over the injury site.  While this can be effective in some applications, the membrane is fragile and costly, and only available in the most advanced surgical settings. Synthetic bandages are available for more severe open globe injuries, but they lack the flexibility and transparency needed to restore the globe integrity, and stabilize and monitor the wound until more permanent treatments can be pursued. Luna’s biologically-inspired ocular repair dressings, known as BIOcular™, have been designed to fill the unmet need of currently available options.

Luna’s BIOcular™ dressings consist of a unique nanofiber-reinforced hydrogel that mimics the native structure of the eye. It is easily handled, can be applied with sutures or photochemical tissue bonding, and is being designed to deliver therapeutics and antimicrobials to the ocular surface. The mechanical and biological properties of the dressing can be tailored to suit the application, with various chemistries available for targeted wound healing or structural repair.

BIOcular™ is an Advanced Synthetic Dressing for Corneal Surface Injuries

In Luna’s BIOcular™ dressings, the healing properties of the amniotic membrane are mimicked using a biopolymeric hydrogel, and the mechanical properties are enhanced using nanofiber reinforcements that effectively mimic the minimally vascularized and highly oriented natural structure of ocular tissue. The dressing is designed to treat corneal abrasions and ulcers found on surface of the eye. It will naturally resorb over time, will provide bacteria penetration resistance, and will be compatible with both traditional and sutureless bonding techniques. The dressing has a refractive index of 1.335 (cornea is 1.38), visible light transmission of 85%, is compatible with primary human corneal epithelial cells, and can be adjusted such that complete degradation occurs reproducibly between 5 minutes and 4 weeks.

BIOcular-X™ is Designed to Treat More Severe Open-Globe Injures

Luna is also developing the BIOcular-X™ dressing, an alternate formulation with increased mechanical integrity of the dressing to enable application to severe corneal lacerations and open globe injuries. This dressing is designed for application over severe ocular injuries to stabilize the globe until more permanent treatments (such as corneal transplants) can be performed. Whereas the BIOcular™ dressing is designed to be applied to corneal surface injuries and resorb as the ocular surface heals, BIOcular-X™ is designed to stabilize the globe and initiate healing, but eventually be removed in favor of more definitive treatment. By adjusting the formulation, Luna can control the elastic modulus (1 – 200 MPa), peak tensile stress (1 – 27 MPa), optical transparency (60 – 95%), and degree of water impermeability of the dressing. All chemistries have been demonstrated to have a refractive index of 1.33-1.34, appropriate oxygen transmissibility, and cytocompatibility with primary human corneal epithelial cells and bovine corneal endothelial cells. Samples have shown stability of at least 4 weeks in normal saline.

BIOcular™ Dressings have a Bright Future

The base BIOcular™ and BIOcular-X™ dressings are being developed as the first two members of a family of products to suit a multitude of ocular applications. Luna envisions the application of its BIOcular™ dressing as a corneal-surface repair material or open-globe stabilizing bandage, but also as a therapeutic delivery device, or a cell-seeded scaffold for use primarily in wound healing and ocular repair. In related programs, Luna has demonstrated controlled release of analgesics such as lidocaine from nanofiber-based dressings. Luna is now expanding this research to include the controlled release of other therapeutics, growth factors, and antimicrobial agents of direct relevance to eye health. Luna is also investigating sutureless application of these dressings using a photoactive dye and the application targeted light to induce adhesion to the ocular surface. This process will minimize the need for sutures on already inflamed and compromised tissue.

Luna’s BIOcular™ dressing can be prepared with a photoactive dye that allows suture-free application to the surface of the eye, reducing inflammation and complications associated with the use of stitches on the eye.

Luna will be presenting its BIOcular™ dressing development efforts during the upcoming 10th World Biomaterials Congress in Montreal, Canada. Please attend our poster presentation in Session 1A between 3:00 – 4:30 pm on May 18, 2016 and discuss this exciting technology with us!

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