It’s time to find new targets for brain diseases instead of just pursuing old ones

It’s time to find new targets for brain diseases instead of just pursuing old ones

Brad Margus

It was still more sobering to discover that developing treatments for central nervous system (CNS) diseases, which affect the brain and spinal cord, is even harder to do. CNS drugs have longer development times and higher failure rates than non-CNS drugs, largely because of the brain’s enormous complexity. As a result, for CNS diseases like Parkinson’s disease, physicians are limited to prescribing symptomatic treatments like L-dopa and a long list of drugs developed more than 50 years ago for psychiatric disorders.

For common neurodegenerative diseases like Alzheimer’s, nothing has worked so far to slow the course of the disease in spite of billions of dollars of investment by industry and the nonprofit and government sectors. The failure rate has been an amazing 100%.

Fortunately, there have been a handful of recent partial successes in CNS drug development. A few pediatric diseases like spinal muscular atrophy are now being treated by replacing or silencing the disrupted genes that cause them. My foundation will be funding an N-of-one clinical trial at Boston Children’s Hospital this fall to test a new gene therapy approach in a girl who has my sons’ disease. But for later-onset brain diseases like Alzheimer’s and Parkinson’s that strike millions of people as they grow older, only a small fraction of patients carry disease-causing changes in their DNA, and gene-targeting strategies based on this knowledge are still largely unproven...