Drug offers hope for the mentally disabled

by Cesar Chelala

NEW YORK — I remember my friend’s face when he told me that his daughter had been born with a severe mental disability.

“It was as if somebody had pointed a gun to my head,” he told me.

For as long as they have been known, mental disabilities have been the cause of profound unhappiness in parents of children born with them as well as in the children themselves.

Now there is hope.

An experimental drug made by Novartis, a Swiss pharmaceutical firm, has been shown to improve behaviors associated with mental disabilities and autism in people affected with Fragile X Syndrome, the most common inherited cause of these mental disabilities.

Although the results have been produced in a small clinical trial involving only a few dozen patients, the finding offers the possibility of advances in the near future.

If further trials in larger populations produce equally good or better results, they could offer hope in the field of autism research. Between 10 and 15 percent of autism cases result from Fragile X Syndrome or other genetic defects.

Also, even though Novartis tested the drug only in adults, experts believe that it could be even more effective in young children, whose brains are still in development and who thus are more likely to respond positively to the drug.

It is estimated that as many as one in 35 people in the United States have mental disabilities, which amounts to approximately 3 percent of the population. Also, every five minutes a child is born with a mental disability. The annual cost to the country is more than $6 billion in special services and lost wages.

Mentally disabled children have impaired or incomplete mental development, and are limited in their ability to learn and in their capacity to apply learning. Most of those affected have mild or moderate mental disability, and with proper education, training and understanding, they can become productive members of society. The limitations in cognitive functioning will cause them to learn and develop more slowly than children who are not affected by this condition.

Fragile X Syndrome is caused by a genetic mutation in chromosome X in which part of the instructions in the gene are repeated several times. When that section of the gene is repeated 200 or more times, the body shuts off the gene. As a result, the protein that is normally produced by that gene is not produced any longer, or if it is produced, is defective. This is what causes the wide variety of symptoms among those afflicted with Fragile X Syndrome.

The protein normally produced by chromosome X acts as a sort of coordinator of information among brain synapses (connections between nerve cells), helping to stop or slow down brain signaling at critical intervals. Regulating the flow of information among brain cells is crucial for the brain’s ability to learn and develop normally.

Until recently many researchers believed that the only approach to dealing with mental disabilities was through a process of rehabilitation, not medication. The improvement in some patients’ behavior after administration of a drug suggests a whole new panorama of possibilities.

The new studies confirm some previous studies in mice with the Fragile X mutation: The drug was able to reduce some abnormalities such as seizures, atypical rates of protein synthesis and other molecular defects.

If further authenticated, these findings will show that however hard the wall of mental disabilities seems, we can still break through to the other side.

Cesar Chelala, Ph.D., M.D., was a researcher in microbial genetics at the Public Health Research Institute, New York.