Vanoxerine, also known as GBR-12909, is a piperazine derivative exhibiting potent selective inhibition of sodium-dependent dopamine reuptake transporters. Vanoxerine has been in clinical trials for Parkinsonism, depression and cocaine addiction but lacked efficacy. Vanoxerine has also been observed as a potent blocker of the following channels: cardiac hERG/IKr potassium channel, Calcium channel, voltage-dependent, L type, alpha 1C subunit (also known as Cav1.2) and voltage-gated sodium channel Nav 1.5. Vanoxerine was studied as a potential treatment for atrial fibrillation. However, phase III clinical trials for this condition were terminated because of cardiac safety concerns. Research also indicates that vanoxerine may have additional mechanisms of action including antagonist action at nicotinic acetylcholine receptors (nAChRs).

Protocatechuic acid (3,4-dihydroxybenzoic acid, PCA) is a simple phenolic acid. It is found in a large variety of edible plants and possesses various pharmacological activities. This bioactive compound is famous for its biological properties and pharmacological activities such as: antioxidant, antibacterial, anticancer, antiulcer, antidiabetic, antiaging, antifibrotic, antiviral, anti-inflammatory, analgesic, antiatherosclerotic, cardiac, hepatoprotective, neurological and nephroprotective. The neuroprotective effects of PCA, extracted from Alpinia oxyphylla, on H2O2 resulted in apoptosis and oxidative stress in cultured PC12 cells. Apoptotic cell death by H2O2 was dose-dependent. Enhanced effect of PCA on protecting PC12 cells against apoptosis, augmented glutathione (GSH) level and an increase in catalytic activity was investigated by flow cytometric analysis. In cytotoxic assays, PCA causes cell death in HepG2 cancerous cell line of liver showing that PCA stimulates the c-Jun N-terminal kinase (JNK) and p38 subgroups of the mitogen-activated protein kinase (MAPK) family. Treatment with PCA decreased OVA-induced airway hyper-responsiveness to inhaled methacholine. Cell inflammation and mucus hypersecretion was also decreased by PCA. Thus, PCA can be useful for treating asthma. Experimental studies strongly support the role of protocatechuic acid in the prevention of neurodegenerative processes, including Alzheimer's and Parkinson's diseases, due to its favorable influence on processes underlying cognitive and behavioral impairment, namely accumulation of the β-amyloid plaques in brain tissues, hyperphosphorylation of tau protein in neurons, excessive formation of reactive oxygen species and neuroinflammation.

The investigational psychopharmacologic drug candidate CP 615003 (NGD 91-3) is a potent subtype-selective partial agonist at the GABA-A receptor complex. It was designed to be fast acting without causing the sedation, memory impairment, addiction or potentiation of effects of alcohol associated with conventional anti-anxiety medication. Tissue distribution studies conducted during early clinical development of CP 615003 suggested limited brain penetration. In the Phase II clinical study, subjects tested at the high dose of NGD 91-3 showed a trend toward efficacy that did not achieve statistical significance.

C16 (PKRi) is a selective inhibitor of the enzyme double-stranded RNA-dependent protein kinase (PKR). PKRi prevents striatal neurodegeneration and improves behavioral outcomes in a chemically induced mouse model of Huntington's disease, the efffect mediated by off-target inhibition of CDKs. PKRi restored memory deficit in a mouse model of Alzheimer's disease. In a mouse model of colon-26 adenocarcinoma, treatment with C16 lead to a significantly higher level of blood glucose and lower level of serum triglyceride compared with placebo group, which indicates potential use for alleviation of cachexia.