Schizophrenia is a devastating neurodevelopmental disorder affecting approximately 1% of the population. While the emergence of antipsychotics such as haloperidol, clozapine, and olanzapine has improved the lives of people suffering from this disease, these drugs are not effective on all symptom domains, and they have a range of serious side effects, including cardiovascular, metabolic, immunological, and neurologic effects. Therefore, new treatment options, particularly therapeutics targeting the negative and cognitive symptom domains, are desperately needed. Recent genetic and pharmacological studies have demonstrated that catechol-O-methyl transferase (COMT) plays a significant role in regulating prefrontal cortical dopamine levels, which are important for several aspects of cognition that are impaired in schizophrenia. COMT inhibition has been shown to improve working memory in preclinical and clinical studies; however, the current clinically available COMT inhibitors suffer from poor pharmacokinetics, inadequate brain penetration, and liver toxicity. Based on preliminary studies that have identified new COMT inhibitor leads, we propose to design novel COMT inhibitors that are optimized in terms of potency, selectivity, brain penetration, and pharmacokinetics. We propose a comprehensive research program that will design, synthesize and test new COMT inhibitors for potency, selectivity, brain penetration, and pharmacokinetics based on our new leads (Specific Aims 1 and 3). Structural biology and modeling studies will better define differences between the membrane-bound and soluble forms of COMT (Specific Aim 2) and contribute to design of new inhibitors. Leading compounds will be evaluated in rodent models of behavior to assess improvements in cognition as well as to evaluate confounding side effects (Specific Aim 4). The iterative cycle of drug discovery will lead to identification of a compound that can not only explore the role of COMT inhibition in the context of in vivo cognition models, but also be a candidate for clinical development. This project is ultimately directed toward the discovery of a novel treatment for the debilitating cognitive impairment seen in many patients with schizophrenia, for which there are currently no effective options. The compounds identified here will not only allow us to explore the role of COMT inhibition in the context of in vivo cognition models but also serve as drug candidates for preclinical evaluation as novel treatments for cognitive impairment in schizophrenia.

Public Health Relevance

While antipsychotic medications can often treat the positive symptoms of schizophrenia such as hallucinations and delusions, many schizophrenic patients suffer significant cognitive impairment and are unable to function successfully in society. At present, none of the FDA-approved treatments are able to reverse these cognitive deficits, leaving patients dependent on family, friends, and institutions for care. This project will capitalze on exciting new developments in the chemistry and biology of catechol-O-methyl transferase (COMT) to develop the first new drug candidates to treat this debilitating cognitive impairment.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Research Project (R01)
Project #
5R01MH107126-05
Application #
9648188
Study Section
Drug Discovery for the Nervous System Study Section (DDNS)
Program Officer
Michelotti, Enrique
Project Start
2015-04-15
Project End
2021-02-28
Budget Start
2019-03-01
Budget End
2021-02-28
Support Year
5
Fiscal Year
2019
Total Cost
Indirect Cost
Name
Lieber Institute, Inc.
Department
Type
DUNS #
963044529
City
Baltimore
State
MD
Country
United States
Zip Code
21205
Buchler, Ingrid; Akuma, Daniel; Au, Vinh et al. (2018) Optimization of 8-Hydroxyquinolines as Inhibitors of Catechol O-Methyltransferase. J Med Chem 61:9647-9665