A novel polymer gel for the delivery of local therapies to intracranial tumors: In vivo safety evaluation

The treatment of intracranial malignancies is limited by the ability of systemically administered therapies to cross the blood-brain barrier. Royer resorbable matrix, or R-Gel, is a dextran polymer administered in liquid form via needle injection. Within minutes of preparation, the polymer forms a gel and subsequently solidifies, thereby conforming to the dimensions of the injection cavity. R-Gel can accommodate a wide variety of therapeutic agents that may provide new options for local treatment delivery. This preclinical study evaluates the neurotoxicity of R-Gel implanted in the rat brain. Fifteen rats underwent intracranial administration of R-Gel (N = 9) or saline (N = 6) were monitored for systemic and neurotoxicity, and sacrificed at pre-determined time points. Animals that received the R-Gel injection demonstrated no behavioral changes or weight loss. Histopathologic analysis revealed an inflammatory response in both groups on day 3 and day 7 after implantation, which resolved by day 42. These results suggest that intracranial R-Gel is well tolerated. Therapeutic studies of chemotherapy-complexed R-Gel are underway.