Ocular Drug Delivery Devices for Improved Postoperative Cataract Care

DESCRIPTION (provided by applicant): In the past three decades intraocular lens (IOL) replacement has become the standard of care for treating cataracts, the world's leading cause of blindness. Tremendous advances have been made both in the design of the IOL and in the surgical procedure. The newest lenses can correct refractive errors and some lenses are beginning to appear that have the potential to restore accommodation. Extracapsular cataract surgery (ECCS) is the most common ophthalmologic procedure performed worldwide; during this procedure the old lens is removed from the capsular bag either intact or after emulsification, and an artificial IOL is inserted into the capsular bag. In spite of these advances, ECCS is not without its problems. A number of patients develop serious infections (endophthalmitis) and a large percentage of patients develop significant post surgical inflammation. This project is focused on increasing access to care by radically reducing the associated costs and incidence of cataract surgical complications through the development of a simple and inexpensive drug delivery system with two distinct components which the physician implants at the time of surgery. One bead-shaped device will integrate dexamethasone for the prevention of inflammation. The other bead is loaded with an antibiotic (ofloxacin) for the prevention of postsurgical infection. By delivering the two medications in separate beads, the physician will maintain flexibility in customizing patient care. Eye drops, the current standard-of-care, generally achieve less than 1% penetration into the eye, and present significant compliance issues due to the multiple daily doses required. Ocular implants pre-loaded with drug can release a constant amount of medication over pre-set treatment periods, remove compliance issues and bypass the physiological barriers to the eye. The scope of this trial encompasses the creation of a separate drug delivery device for each medication and an extensive in vitro examination of their individual bioactivity and release profiles. An in vivo verification of the device safety and efficacy will then be conducted in New Zealand White rabbits over a period of 42 days. Inson's overall objective is the commercialization of two revolutionary drug eluting beads, one of which contains an antibiotic and the other an anti-inflammatory drug. When used together they will radically increase patient access to care, especially in underdeveloped areas of the world. We believe the devices will also reduce cataract surgical complications as well as their associated costs. The work we propose is a critical step on the way towards achieving this important goal. (PUBLIC HEALTH RELEVANCE STATEMENT): Cataract surgery, in which the cataractous natural lens is replaced with an artificial intraocular lens, is the most common ophthalmologic procedure worldwide with an estimated 38 million procedures performed annually (WHO estimate). While tremendous advances have been made in the lenses and the procedure, significant issues remain - cost of the surgery and post-op care, patient compliance with post-surgical care, infection, secondary cataracts and post-surgical inflammation. The development of drug eluting intraocular beads that eliminate the primary complications of infection and inflammation will both improve surgical outcomes and reduce the overall cost of care, making IOL replacement available to more patients (particularly in rural and underdeveloped areas).