Xanomeline (LY-246,708) is an orthosteric muscarinic acetylcholine receptor (mAChR) agonist, often referred to as M1/M4-preferring. It is also known to act as a M5 receptor antagonist. Xanomeline was studied in clinical trials phase I in schizophrenia. In Phase II clinical trials in Alzheimer’s patients, xanomeline significantly improved several measures of cognitive function, yet produced unwanted side effects that limited patient compliance. The side effects seem to be associated with rapid metabolism of the alkyloxy side chain following oral administration, resulting in a nonselective, yet active compound with limited therapeutic utility. Despite a second Phase II clinical trial with a patch formulation, the liabilities of xanomeline still outweigh its benefits.

Revefenacin (trade name Yupelri is a long-acting muscarinic antagonist developed by Mylan Ireland ltd for the treatment of chronic obstructive pulmonary disease (COPD). It has similar affinity to the subtypes of muscarinic receptors M1 to M5. In the airways, it exhibits pharmacological effects through inhibition of M3 receptor at the smooth muscle leading to bronchodilation. The competitive and reversible nature of antagonism was shown with human and animal origin receptors and isolated organ preparations. In preclinical in vitro as well as in vivo models, prevention of methacholine- and acetylcholine-induced bronchoconstrictive effects was dose-dependent and lasted longer than 24 hours.

Neratinib (HKI-272) is a pan-HER inhibitor, this irreversible tyrosine kinase inhibitor binds and inhibits the tyrosine kinase activity of epidermal growth factor receptors, EGFR (or HER1), HER2 and HER4, which leads to reduced phosphorylation and activation of downstream signaling pathways. Neratinib is a modified form of the discontinued compound pelitinib, and was originally being develoAdditionally, phase II development of oral neratinib as a neoadjuvant therapy for breast cancer, as a second-line therapy for non-small cell lung cancer, and for other solid tumours is also in progress in numerous countries worldwide. ped by Wyeth (later Pfizer). Oral neratinib is awaiting approval as an extended adjuvant therapy for breast cancer in the EU and in the US. Blocking HER2 function by a small molecule kinase inhibitor, such as neratinib, represents an attractive alternate strategy for the growth inhibition of HER2-positive tumours.

Umeclidinium (used as a bromide salt) is a long-acting, antimuscarinic antagonist, often referred to as an anticholinergic, developed for the treatment of chronic obstructive pulmonary disease (COPD) (alone and in combination with Vilanterol - long-acting beta2-adrenergic agonist). Umeclidinium has similar affinity to the subtypes of muscarinic receptors M1 to M5 with Ki values of 0.16 nM, 0.15 nM, 0.06 nM, 0.05 nM and 0.13 nM for M1, M2, M3, M4 and M5, respectively. Umeclidinium is selective against mAChR over other unrelated receptors or channels such as κ and σ opiod receptors, Na+ channel and dopamine transporter. In the airways, it exhibits pharmacological effects through the inhibition of M3 receptor at the smooth muscle leading to bronchodilation. There is potential for an additive interaction with concomitantly used anticholinergic medicines.

Aclidinium is a long-acting, competitive, and reversible anticholinergic drug that is specific for the acetylcholine muscarinic receptors. It binds to all 5 muscarinic receptor subtypes to a similar affinity. It has a much higher propensity to bind to muscarinic receptors than nicotinic receptors. FDA approved on July 24, 2012. Aclidinium's effects on the airways are mediated through the M3 receptor at the smooth muscle to cause bronchodilation. Prevention of acetylcholine-induced bronchoconstriction effects was dose-dependent and lasted longer than 24 hours.

Fesoterodine (trade name Toviaz) is a prodrug of 5-hydroxymethyl tolterodine, which is also the active metabolite of tolterodine. Fesoterodine and its active metabolites are nonsubtype selective, competitive antagonists of human muscarinic receptors, but 5-hydroxymethyl tolterodine has greater potency than the parent compound. A prodrug approach was necessary for systemic bioavailability of 5-hydroxymethyl tolterodine after oral administration. Fesoterodine was originated by Schwarz Pharma (later a subsidiary of UCB) and is being developed by Pfizer for the treatment of overactive bladder and urinary urge incontinence. The agent is launched in several countries for the treatment of overactive bladder, including the US, Japan, Canada, Europe and Asia.

Paliperidone (9-OH-risperidone) is the primary active metabolite of the older antipsychotic risperidone. While its specific mechanism of action is unknown, it is believed that paliperidone and risperidone act via similar if not the same pathways. It has been proposed that the drug's therapeutic activity in schizophrenia is mediated through a combination of central dopamine Type 2 (D2) and serotonin Type 2 (5HT2A) receptor antagonism. Paliperidone is also active as an antagonist at alpha 1 and alpha 2 adrenergic receptors and H1 histaminergic receptors, which may explain some of the other effects of the drug. Paliperidone was approved by the FDA for treatment of schizophrenia on December 20, 2006. Very common adverse effects are: headache, tachycardia, somnolence and insomnia.

Varenicline is a partial nicotinic acetylcholine receptor agonist, designed to partially activate this system while displacing nicotine at its sites of action in the brain. Varenicline is an alpha-4 beta-2 neuronal nicotinic acetylcholine receptor partial agonist. The drug shows high selectiviyty for this receptor subclass, relative to other nicotinic receptors (>500-fold alpha-3 beta-4, >3500-fold alpha-7, >20,000-fold alpha-1 beta gamma delta) or non-nicotinic receptors and transporters (>2000-fold). The drug competitively inhibits the ability of nicotine to bind to and activate the alpha-4 beta-2 receptor. The drug exerts mild agonistic activity at this site, though at a level much lower than nicotine; it is presumed that this activation eases withdrawal symptoms. Varenicline is sold under the trade name Chantix and Champix, it is indicated for use as an aid to smoking cessation treatment.

Darifenacin is a selective muscarinic receptor M3 antagonist which was approved by FDA for the treatment of overactive bladder.