Magnetic Delivery of Drugs to the Middle Ear
- Diego Preciado, M.D.
- Ben Shapiro, Ph.D.
- Didier Depireaux, Ph.D.
Acute otitis media (AOM) is the leading cause of physician visits by children. Currently, 42 percent of all antibiotics prescribed in the U.S. are for the treatment of AOM. Approximately 20 percent of children with AOM go on to develop chronic otitis media with effusion (COME). Although systemic antibiotics may reduce duration and severity of symptom burden and duration of AOM in children, they have no effect on the clearance of middle ear fluid. For this reason, tympanostomy tube placement under general anesthesia for treatment of recurrent AOM or COME is the most common pediatric surgical procedure requiring anesthesia in the U.S. There are no effective non-surgical treatments for COME, nor are there medical treatments that block the progression of AOM to COME. In collaboration with Children’s National Health System, the Bio-engineering group at the University of Maryland, led by Dr. Ben Shapiro, has developed a topical non-invasive middle-ear therapy delivery system that does not require systemic antibiotic administration, surgery, tympanic membrane puncture, or anesthesia. The system is based on the Dr. Shapiro’s magnetic injection technology, which uses magnetic forces to transport bio-compatible nano-particles through the tympanic membrane into the middle ear. This technology has been validated in preliminary pre-clinical animal experiments, both for middle and inner ear delivery.
Phase I of this project focused on showing that we could magnetically deliver drugs to the middle ear without ear drum puncture (aim 1) and that the treatment was safe (no toxicity or hearing damage, aim 2). Both these aims were achieved in a rat animal model. In phase II, using an accepted rat animal model of middle ear infections, we are studying the efficacy of this approach. Currently, we are testing whether the transtympanic magnetic delivery of sulfonamide and oflaoxacin, both front line ototopical antimicrobials, are effective at clearing bacteria from a middle ear infection in the animals. Initial preliminary data demonstrates reduced evidence of middle ear inflammation and infection with the treatment over controls.