Global incidence rates for peripheral nerve injury (PNI) are not well aggregated. However, US data collected shows that 20 million Americans suffer from peripheral nerve injury caused by trauma and medical disorders. When a tension-free early repair is possible, microsurgical direct nerve repair with epineural sutures remains the gold standard of care. The current standard for large nerve defects is autologous nerve grafts. However, disadvantages for this treatment approach include risk of neuroma formation and loss of donor nerve function. Acellular nerve conduits limit the disadvantages associated with autologous grafts. However, conduits are still insufficient for large deficits and require a combination of pharmacological and molecular therapies to yield prime results. Research indicates that these therapy additions should focus on both axonal regeneration and Schwann cell renewal. Insulin-like growth factor (IGF-1) has shown promising results because it optimizes axonal regeneration and Schwann cell renewal simultaneously. Previously reported encapsulation methods for growth factors either release the payload too rapidly or achieve prolonged presence through covalent conjugation. Therefore, there is a strong need to develop a delivery system that can provide sustained release of small proteins for an extended duration while maintaining encapsulation efficiency and bioactivity.
Karim Sarhane MD at Johns Hopkins created a nanoparticle-based delivery system that provides sustained release of bioactive insulin like growth-factor 1 (IGF-1) for 20 days in vitro to denervated nerve and muscle tissue within the peripheral nervous system. The delivery system fulfills the need to create a nanoparticle-based drug delivery system that provides sustained and controllable release of IGF-1 without sacrificing on encapsulation efficiency or retention of bioactivity. Preliminary results support potential to improve functional outcomes for PNI patients suffering from severe injury, presenting a significant value proposition with potential to improve significant sensory and motor impairments associated with 4th and 5th degree injury.