Vestipitant, also known as GW597599, is a neurokinin1 receptor antagonist that was being developed by GlaxoSmithKline for the treatment of postoperative nausea and vomiting. Vestipitant is one of the most potent and selective NK(1) receptor antagonists ever discovered, showing appropriate pharmacokinetic properties and in vivo activity. Its actions support the utility of NK(1) receptor blockade in the alleviation of anxiety and, possibly, depression. It was under development as a potential antiemetic and anxiolytic drug, and as a treatment for tinnitus and insomnia. Vestipitant was shown to improve sleep maintenance in patients with primary insomnia, with no associated next-day cognitive impairment. The effects on wake after sleep onset and total sleep time were maintained following repeated dosing. Vestipitant has anxiolytic properties and a good safety profile. Vestipitant was investigated for potential effect against chronic tinnitus as a stand-alone treatment and in conjunction with a selective serotonin reuptake inhibitor, paroxetine. Although well-tolerated vestipitant, alone or in combination with paroxetine, was not effective in ameliorating tinnitus in this patient group.

PF-03654746 is a potent, selective antagonist of the human H3 receptor, developed by Pfizer. It was in the clinical trial phase II for the treatment of excessive daytime sleepiness (EDS) associated with narcolepsy, Tourette syndrome as well as potential anti-allergy applications and in phase I of clinical trial for the treatment of Schizophrenia and Alzheimer's disease, but these investigations were discontinued.

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).

Lodoxamide ethyl, diethyl N,N'-(2-chloro-5-cyano-m-phenylene) dioxamate, is an orally active candidate for the treatment of asthma and other allergic diseases. Lodoxamide ethyl prevents mast cell mediator release during allergic reactions in rats, guinea pigs, and monkeys at doses well below toxic levels. Lodoxamide ethyl does not interfere with antigen-antibody interaction, does not antagonize the effects of histamine or slow-reacting substance of anaphylaxis, and does not have direct antiinflammatory effects. Lodoxamide ethyl has been proven capable of preventing bronchospasm in humans when the subject was given 1, 3, or 10 mg of the drug orally prior to challenge with an antigen.