working memory: nootropics and compounds | sci-wiki

ABT-089

ABT-089, also known as pozanicline, is a synthetic small molecule that acts as a partial agonist at neuronal nicotinic acetylcholine receptors, with selectivity for the α4β2 subtype. Developed by Abbott Laboratories, it was investigated as a cognitive enhancer and as a candidate treatment for attention-deficit/hyperactivity disorder (ADHD) and other cognitive conditions.

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Nootropic

ABT-126

ABT-126 was AbbVie's (formerly Abbott's) selective alpha7 nicotinic acetylcholine receptor agonist, developed for both cognitive impairment in schizophrenia and Alzheimer's disease. The alpha7 receptor is heavily expressed on hippocampal and prefrontal circuits involved in learning and attention, and it was a hot target through the 2010s after epidemiological observations tied smoking to modest cognitive benefits in schizophrenia patients. A Phase 2 trial found a real procognitive signal, but only in nonsmokers; smokers, whose alpha7 receptors were presumably already saturated or desensitized by nicotine, showed nothing. A larger Phase 2b confirmatory trial in nonsmokers, and a separate one in smokers, both failed to show meaningful benefit, and AbbVie discontinued the program around 2016 along with much of the industry's broader retreat from alpha7 agonists.

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Nootropic

CX-717

CX-717 is a later, more brain-penetrant ampakine (Cortex Pharmaceuticals, later RespireRx) notable for offsetting sleep-deprivation cognitive decline in nonhuman primates and, at high dose, in humans, plus a distinct adult-ADHD development track. It has a 'low-impact' AMPA-PAM profile.

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Nootropic

Farampator

Farampator (CX-691 / Org 24448) is an investigational ampakine, a positive allosteric modulator of AMPA-type glutamate receptors, advanced through the Cortex Pharmaceuticals / Organon program. It slows AMPA-receptor deactivation and desensitization to strengthen fast excitatory transmission and long-term potentiation, and in animals it raises hippocampal and prefrontal acetylcholine, prefrontal dopamine, and hippocampal BDNF mRNA. It is best known for a single, unusually instructive human trial in which one 500 mg dose improved short-term memory yet impaired episodic memory in healthy elderly volunteers.

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Nootropic

Ispronicline

Ispronicline traces its chemistry back to nicotine research originally funded by tobacco company R.J. Reynolds, which spun off its pharmaceutical research arm into Targacept in the late 1990s. The resulting compound was a partial agonist at alpha4beta2 neuronal nicotinic receptors, designed to capture nicotine's attention- and memory-enhancing effects without its addictive and cardiovascular baggage. AstraZeneca partnered with Targacept and pushed ispronicline (as AZD3480) into a Phase IIb dose-finding trial for mild-to-moderate Alzheimer's disease as well as separate studies for adult ADHD. The Alzheimer's trial, published in 2011, failed to show a robust cognitive benefit, and AstraZeneca discontinued the partnership around 2010-2011, part of a broader collapse of the nicotinic-receptor cognition-enhancement field that also claimed several competing programs.

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Nootropic

MK-0777

MK-0777 was a Merck compound built to be a benzodiazepine-like drug without the sedation; it selectively potentiated GABA-A receptors carrying the alpha2 or alpha3 subunit instead of hitting alpha1 (the subunit responsible for benzodiazepine sedation and abuse liability). The idea came out of University of Pittsburgh postmortem work showing that GABA neurotransmission onto pyramidal cells in the schizophrenic prefrontal cortex is weakened, which was proposed as a root cause of the working-memory deficits in the disease. A small 2008 open-label-adjacent proof-of-concept trial in chronic schizophrenia patients found real improvements on working-memory tasks and increased frontal gamma power, which made a fair bit of noise in the field. A larger, properly randomized follow-up then failed to replicate the benefit, and Merck quietly let the program lapse; it never advanced past early Phase II.

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Nootropic

T-588

T-588 came out of Toyama Chemical in Japan as a multi-target cognitive enhancer built for the vascular-dementia and post-stroke cognitive-impairment niche that Japanese pharma researched heavily in the 1990s, a market segment Western companies mostly ignored. Rather than hitting one clean receptor, it increased acetylcholine and noradrenaline release in the cortex and hippocampus, blocked an outward potassium current in CA1 neurons, and protected cerebellar granule cells from glutamate excitotoxicity, a genuinely broad-spectrum profile aimed at both boosting transmission and shielding neurons from ischemic damage. It compensated for scopolamine-induced learning impairment and improved working memory after simulated cerebral ischemia in rodents, but like most Japanese vascular-cognition compounds of its era, it never crossed into Western regulatory pipelines and faded from view once academic interest moved to other neuroprotective targets.

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