HT-2157 (former development code SNAP-37889) is a drug which acts as a selective non-peptide
antagonist
An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.GAL-3, which is usually activated by the
neuropeptide
Neuropeptides are chemical messengers made up of small chains of amino acids that are synthesized and released by neurons. Neuropeptides typically bind to G protein-coupled receptors (GPCRs) to modulate neural activity and other tissues like the ...
galanin
Galanin is a neuropeptide encoded by the ''GAL'' gene, that is widely expressed in the brain, spinal cord, and gut of humans as well as other mammals. Galanin signaling occurs through three G protein-coupled receptors.
Much of galanin's functio ...
. Blocking this receptor with HT-2157 produced increased
serotonin
Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...
release, as well as producing
antidepressant
Antidepressants are a class of medications used to treat major depressive disorder, anxiety disorders, chronic pain, and addiction.
Common side effects of antidepressants include Xerostomia, dry mouth, weight gain, dizziness, headaches, akathi ...
and
anxiolytic
An anxiolytic (; also antipanic or anti-anxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxie ...
effects in animal studies, and it was also being researched for treatment of
cognitive dysfunction
Neurocognitive disorders (NCDs), also known as cognitive disorders (CDs), are a category of mental health disorders that primarily affect cognitive abilities including learning, memory, perception, and problem-solving. Neurocognitive disorders in ...
. All human clinical trials were terminated due to safety concerns however, and new GAL-3 antagonists are now being sought instead.