The research of Elliott Richelson, M.D., and his group is focused on drug discovery in the area of neuropsychiatric diseases. These diseases include schizophrenia, Parkinson's disease, pain (including neuropathic pain), depression and attention deficit disorder. All research currently is preclinical and uses animal models.
The targets for schizophrenia, Parkinson's disease and pain are receptors for the endogenous peptide called neurotensin, which is 13 amino acids in length. Although first discovered in the brain, it was later found elsewhere in the body, including the gastrointestinal tract. All the activity of the peptide resides in the last five or six amino acids.
The approach by Dr. Richelson and his team has been to design peptides (five and six amino acids in length) that are stable to degradation by enzymes in the body. They have published a large number of preclinical studies that support the use of these peptides to treat schizophrenia, Parkinson's disease and various types of pain (somatic, visceral and neuropathic).
The targets for depression and attention deficit disorder are neurotransmitter transporters. For depression, Dr. Richelson's group has discovered novel compounds that block transporters for serotonin, norepinephrine and dopamine. These have been called triple re-uptake inhibitors. His group also has novel compounds that selectively and potently block dopamine transporters and may be useful for treatment of attention deficit disorder.
Significance to patient care
There are unmet needs for the drug treatment of all the diseases listed above. For example, current drugs for the treatment of schizophrenia treat the hallucinations and delusions, but not the cognitive problems that help to devastate the lives of these patients. In addition, these drugs often have side effects that cause patients to stop taking them. It is hoped that targeting neurotensin receptors will provide more effective treatment for schizophrenia, including improvements in cognition, with fewer side effects.
Also, there are unmet needs for the pharmacotherapy of depression, because about 10 to 15 percent of depressed patients do not respond to any drug treatment. Thus, there is a need for new antidepressant drugs, and it is hoped that triple re-uptake inhibitors will provide more effective treatments for depression.