Delivering drugs to targeted brain regions

Michael Cima is the senior author of a new study on targeted drug delivery in the brain. New research from the Graybiel, Cima, and Langer labs at MIT uses a computational approach, one that accounts for the irregular shape of the target brain region, to deliver drugs effectively and specifically.

Brain disorders often arise from dysfunction in specific regions. Targeting such structures is a major therapeutic goal, and demands both overcoming the blood-brain barrier while also being specific to the structures affected by the disorder. 

The COMMAND (computational mapping algorithms for neural drug delivery) system finds balance between the twin challenges of drug delivery by maximizing on-target and minimizing off-target delivery. COMMAND is essentially an algorithm that minimizes an error that reflects leakage beyond the bounds of a specific target area — in this case, the striatum. A second error is also minimized, and this encapsulates the need to target across this irregularly shaped brain region. The strategy to overcome this is to deliver multiple “boluses” to different areas of the striatum to target this region precisely, yet completely.

The number of drug sites applied is kept as low as possible, keeping surgery simple while still providing enough flexibility to cover the target region. In computational simulations, the researchers were able to deliver drugs to compact brain structures, such as the striatum and amygdala, but also broader and more irregular regions, such as the hippocampus.