Memantine is a medication used to slow the progression of moderate-to-severe Alzheimer's disease. It is taken by mouth.
CX717 is an ampakine compound created by Christopher Marrs and Gary Rogers in 1996 at Cortex Pharmaceuticals. It affects the neurotransmitter glutamate, with trials showing the drug improves cognitive functioning and memory.
Tarenflurbil, Flurizan or R-flurbiprofen, is the single enantiomer of the racemate NSAID flurbiprofen. For several years, research and trials for the drug were conducted by Myriad Genetics, to investigate its potential as a treatment for Alzheimer's disease; that investigation concluded in June 2008 when the company announced it would discontinue development of the compound.
Neurokinin 1 (NK1) antagonists (-pitants) are a novel class of medications that possesses unique antidepressant, anxiolytic, and antiemetic properties. NK-1 antagonists boost the efficacy of 5-HT3 antagonists to prevent nausea and vomiting. The discovery of neurokinin 1 (NK1) receptor antagonists was a turning point in the prevention of nausea and vomiting associated with cancer chemotherapy.
The 5-HT3 antagonists, informally known as "setrons", are a class of drugs that act as receptor antagonists at the 5-HT3 receptor, a subtype of serotonin receptor found in terminals of the vagus nerve and in certain areas of the brain. With the notable exceptions of alosetron and cilansetron, which are used in the treatment of irritable bowel syndrome, all 5-HT3 antagonists are antiemetics, used in the prevention and treatment of nausea and vomiting. They are particularly effective in controlling the nausea and vomiting produced by cancer chemotherapy and are considered the gold standard for this purpose.
Latrepirdine is an antihistamine drug which has been used clinically in Russia since 1983.
Pimavanserin, sold under the brand name Nuplazid, is an atypical antipsychotic which is approved for the treatment of Parkinson's disease psychosis and is also being studied for the treatment of Alzheimer’s disease psychosis, schizophrenia, agitation, and major depressive disorder. Unlike other antipsychotics, pimavanserin is not a dopamine receptor antagonist.
Befiradol is an experimental drug being studied for the treatment of levodopa-induced dyskinesia. It is a potent and selective 5-HT1A receptor full agonist.
CCR5 receptor antagonists are a class of small molecules that antagonize the CCR5 receptor. The C-C motif chemokine receptor CCR5 is involved in the process by which HIV, the virus that causes AIDS, enters cells. Hence antagonists of this receptor are entry inhibitors and have potential therapeutic applications in the treatment of HIV infections.
Idalopirdine (INN) (code names Lu AE58054,) is a potent and selective 5-HT6 receptor antagonist under development by Lundbeck as an augmentation therapy for the treatment of cognitive deficits associated with Alzheimer's disease and schizophrenia. As of October 2013 it is in phase III clinical trials.
Intepirdine (INN; developmental codes SB-742457, RVT-101) is a selective 5-HT6 receptor antagonist with potential cognition, memory, and learning-enhancing effects. It was under development by GlaxoSmithKline for the treatment of Alzheimer's disease and demonstrated some preliminary efficacy in phase II clinical trials. GSK chose not to continue development and sold the rights to Axovant Sciences for $5 million in December 2014.
PRX-07034 is a selective 5-HT6 receptor antagonist. It has cognition and memory-enhancing properties and potently decreases food intake and body weight in rodents. PRX-07034 was under development by Epix Pharmaceuticals for the treatment of obesity and cognitive impairment associated with Alzheimer's disease and schizophrenia but upon the company collapsing due to lack of funds the compound was auctioned to another corporation.
Repinotan (BAYx3702), an aminomethylchroman derivative, is a selective 5-HT1A receptor full agonist with high potency and efficacy. It has neuroprotective effects in animal studies, and was trialed in humans for reducing brain injury following head trauma. It was subsequently trialed up to phase II for treatment of stroke, but while side effects were mild and consisted mainly of nausea, repinotan failed to demonstrate sufficient efficacy to justify further clinical trials. However, repinotan continues to be investigated for other applications, and was found to be effective at counteracting the respiratory depression produced by morphine, though with slight reduction in analgesic effects.
Brexpiprazole, sold under the brand name Rexulti among others, is a medication used for the treatment of major depressive disorder and schizophrenia. It is an atypical antipsychotic.
Levofenfluramine (INN), or (−)-3-trifluoromethyl-N-ethylamphetamine, also known as (−)-fenfluramine or (R)-fenfluramine, is a drug of the amphetamine family that, itself (i.e., in enantiopure form), was never marketed. It is the levorotatory enantiomer of fenfluramine, the racemic form of the compound, whereas the dextrorotatory enantiomer is dexfenfluramine. Both fenfluramine and dexfenfluramine are anorectic agents that have been used clinically in the treatment of obesity (and hence, levofenfluramine has been as well since it is a component of fenfluramine). However, they have since been discontinued due to reports of causing cardiovascular conditions such as valvular heart disease and pulmonary hypertension, adverse effects that are likely to be caused by excessive stimulation of 5-HT2B receptors expressed on heart valves.
Drinabant (INN; AVE-1625) is a drug that acts as a selective CB1 receptor antagonist, which was under investigation varyingly by Sanofi-Aventis as a treatment for obesity, schizophrenia, Alzheimer's disease, Parkinson's disease, and nicotine dependence. Though initially studied as a potential treatment for a variety of different medical conditions, Sanofi-Aventis eventually narrowed down the therapeutic indications of the compound to just appetite suppression. Drinabant reached phase IIb clinical trials for this purpose in the treatment of obesity but was shortly thereafter discontinued, likely due to the observation of severe psychiatric side effects including anxiety, depression, and thoughts of suicide in patients treated with the now-withdrawn rimonabant, another CB1 antagonist that was also under development by Sanofi-Aventis.
AVN-211 (CD-008-0173) is a drug which acts as a highly selective 5-HT6 receptor antagonist and is under development by Avineuro Pharmaceuticals for the treatment of schizophrenia. In early 2011, it successfully completed phase IIa clinical trials, with benefits on positive symptoms and some procognitive effects observed, and in mid 2013, phase IIb clinical trials for schizophrenia began. Avineuro Pharmaceuticals also expressed intention to start clinical trials of AVN-211 for Alzheimer's disease in 2015.
AVN-101, a close structural analogue of latrepirdine, is a selective 5-HT6 receptor antagonist which is under development by Avineuro Pharmaceuticals for the treatment of Alzheimer's disease and anxiety disorders. As of November 2013, it was in phase II clinical trials for these indications.
Psychoplastogens are a group of small molecule drugs that produce rapid and sustained effects on neuronal structure and function, intended to manifest therapeutic benefit after a single administration. Several existing psychoplastogens have been identified and their therapeutic effects demonstrated; several are presently at various stages of development as medications including Ketamine, MDMA, Scopolamine, and the serotonergic psychedelics, including LSD, psilocin – the active metabolite of psilocybin, DMT, and 5-MeO-DMT. Compounds of this sort are being explored as therapeutics for a variety of brain disorders including depression, addiction, and PTSD. The ability to rapidly promote neuronal changes via mechanisms of neuroplasticity was recently discovered as the common therapeutic activity and mechanism of action.
AVN-397 is a 5-hydroxytryptamine subtype 6 receptor antagonist drug developed by Avineuro Pharmaceuticals Inc. that can potentially be used to treat Alzheimer's disease and general anxiety disorder (GAD). Avineuro announced that it would start Phase II clinical trials in 2009, and those trials are ongoing as of 2012.
