SBIR-STTR Award

Retinal disorders are a common cause of debilitating vision loss. For many of these conditions, including retinal detachments and macular holes, the only treatment is surgery. The first step of all such surgeries is vitrectomy, the process of removing the vitreous gel through tiny ports in the front of the eye. Each year, 1.1 million vitrectomies are performed globally with 300,000 performed in the US alone, and in the majority of these cases a retinal tamponade is required to be left in the eye to maintain pressure on the retina and aid healing. The global retinal tamponade market was recently valued at USD $64.5 million in 2013 and is predicted to reach USD $77.5 million by 2020. The current state of the art uses either an expansile gas, or a silicone oil to exert pressure on the retina during healing (tamponade). However, neither method is ideal and therefore to address these deficiencies, this proposal develops a novel hydrogel that uses two common synthetic biomedical polymers, namely a modified poly(vinyl alcohol) and poly(ethylene glycol) in a form that creates a unique hydrogel system that is very low viscosity in liquid form but then gels through crosslink formation in the eye. This formulation allows for injection through small surgical ports followed by in vivo expansion resulting in 360-degree retinal tamponade. This unique formulation will eliminate the need for post-operative patient positioning. Additionally, this hydrogel degrades over the period of 3-5 weeks providing a temporary tamponade force before degrading to small molecules that are readily cleared from the eye, thus removing the need for subsequent surgeries to remove the tamponade agent. The resulting device will be more patient friendly with almost no refractive issues and the ability for the patient to be fully mobile. Patient compliance will therefore be improved. In addition, it will also act as a tamponade only for the surgically relevant period of time before clearing naturally through a degradation process reducing costs and improving outcomes.

Public Health Relevance Statement:
Project Narrative Retinal disorders are a common cause of debilitating vision loss and the surgical solutions to repairing them are generally problematic for outcomes and patient compliance. We propose a new hydrogel-based solution that will be optically similar to the native vitreous while exerting a controlled force (tamponade) on the healing retina and then degrade naturally after the end of its useful life. This new device will therefore result in improved patient compliance and outcomes, and reduced surgical visits.

Project Terms:
Address; Air; Alcohols; Anatomy; Animals; base; biomaterial compatibility; Blindness; Cadaver; Compliance behavior; cost; crosslink; Data; design; Devices; Effectiveness; efficacy testing; Environment; ethylene glycol; Excision; experimental study; Eye; Face; Family suidae; Formulation; Gases; Gel; healing; Hydrogels; implantation; improved; improved outcome; In Vitro; in vivo; Inflammation; Injection of therapeutic agent; Lead; Left; Life; Liquid substance; Macular Hole; Materials Testing; Methods; Modeling; Modernization; Nature; New Zealand; novel; Oils; Operative Surgical Procedures; Optics; Oryctolagus cuniculus; Outcome; Pathology; Patient-Focused Outcomes; Patients; Performance; Polymers; Positioning Attribute; Postoperative Period; pressure; Process; Property; repaired; Retina; Retinal; Retinal Detachment; Retinal Diseases; Safety; safety testing; Silicone Oils; small molecule; Sterility; Surgeon; System; Techniques; Testing; Time; Travel; Viscosity; Vision; Visit; Vitrectomy

Retinal disorders are a common cause of debilitating vision loss. For many of these conditions, including retinal detachments and macular holes, the only treatment is surgery. The first step of all such surgeries is vitrectomy, the process of removing the vitreous gel through tiny ports in the front of the eye. Each year, 1.1 million vitrectomies are performed globally with 300,000 performed in the US alone, and in the majority of these cases a retinal tamponade is required to be left in the eye to maintain pressure on the retina and aid healing. The global retinal tamponade market was recently valued at USD $64.5 million in 2013 and is predicted to reach USD $77.5 million by 2020. The current state of the art uses either an expansile gas, or a silicone oil to exert pressure on the retina during healing (tamponade). However, neither method is ideal and therefore to address these deficiencies, this phase 2 proposal extends early work we performed on a novel hydrogel that uses two common synthetic biomedical polymers, namely a modified poly(vinyl alcohol) and poly(ethylene glycol) in a form that creates a unique hydrogel system that is very low viscosity in liquid form but then gels through crosslink formation in the eye. This formulation allows for injection through small surgical ports followed by in vivo expansion resulting in 360-degree retinal tamponade. This unique formulation will eliminate the need for post-operative patient positioning and will degrade to small molecules that are readily cleared from the eye over the period of 3-5 weeks providing a temporary tamponade force before degrading. Data from the Phase 1 supports that the resulting device will be more patient friendly with almost no refractive issues and the ability for the patient to be fully mobile and has proven degradation over 2-3 weeks with no inflammatory response, although this degradation time is also tunable. In this Phase 2 we intend to refine the formulation for improved performance and validate it within a relevant model to demonstrate efficacy.

Public Health Relevance Statement:
Project Narrative Retinal detachment can occur at any age, although it is more common in men, and in over the population over 40 years. State of the art treatments increasingly involve either injection of gas, or a heavy water immiscible liquid, both of which have drawbacks. Here we propose a new hydrogel based tamponade that will allow immediate return to activity and avoid long term complications or surgery by dissolving naturally over time.

Project Terms:
Address; Age; Alcohols; analytical method; Animals; base; Behavior; biomaterial compatibility; Blindness; crosslink; Crosslinker; Data; design; Deuterium Oxide; Device Removal; Devices; efficacy study; efficacy testing; ethylene glycol; experience; experimental study; Eye; Formulation; Gases; Gel; Grant; healing; Hydrogels; improved; In Situ; in vivo; Inferior; Inflammation; Inflammatory Response; Injections; Intention; Lead; Left; Liquid substance; Macular Hole; men; Methods; Modeling; Molecular Weight; novel; Operative Surgical Procedures; Oryctolagus cuniculus; Outcome; Patients; Performance; Phase; phase 1 study; Polymers; Population; Positioning Attribute; Postoperative Period; preclinical study; pressure; Process; programs; Prone Position; Property; Provider; Reaction; Refractive Indices; repaired; response; Retina; Retinal Detachment; Retinal Diseases; Retinal Perforations; Safety; safety study; screening; sex; Silicone Oils; small molecule; success; System; Testing; Time; Validation; Viscosity; Vitrectomy; Work