AZD 9496 was discovered by AstraZeneca as a potent and selective estrogen receptor downregulator (SERD). This drug participated in phase I clinical trials to evaluate the pharmacokinetic profiles and the safety and tolerability of the different forms, formulations, and doses for the treatment of patients with breast cancer.

Fallypride is a high-affinity antagonist of dopamine D2 and D3 receptors. 18F-radiolabeled fallypride is used as a PET tracer to characterize D2/D3 receptors in the brain.

Tetrahydropalmatine is a tetrahydroprotoberberine isoquinoline alkaloid that is a primary active constituent of herbal preparations containing plant species of the genera Stephania and Corydalis. The levo isomer of THP (L-THP) appears to contribute to many of the therapeutic effects of these preparations. The pharmacological profile of L-THP, which includes antagonism of dopamine D1 and D2 receptors and actions at dopamine D3, suggests that it may have utility for treating addiction. Clinical trials where L-THP was used for the treatment of cocaine and heroin addiction have promising results. The clinical trial is planned for the treatment of schizophrenia. L-Tetrahydropalmatine is recorded in the Chinese pharmacopoeia.

ICI-118551 is a selective β2 adrenergic receptor antagonist, that was originally developed for the regulation of blood pressure. ICI-118551 crosses the blood-brain barrier and it was in phase I clinical trials for the treatment of chronic anxiety. Currently, ICI-118,551 has no known therapeutic use in humans although it has been used widely in research to understand the action of the β2 adrenergic receptor, as few other specific antagonists for this receptor are known.

(+)-selfotel ((+)-CGS-19755) is an enantiomer of selfotel, a competitive antagonist at N-methyl-D-aspartate (NMDA)-preferring receptors. The inhibition of NMDA-evoked ACh release from rat striatal slices is stereospecific, with the (+)-enantiomer less potent than the (-)-enantiomer.

Fevipiprant is a selective reversible antagonist of the prostaglandin D2 receptor (also known as CRTH2). It is currently in development for the treatment of allergic diseases.

(R)-Mequitazine or V0162 (10-[(3R)-1-azabicyclo[2.2.2]oct-3-ylmethyl]-10H-phenothiazine) is an anticholinergic enantiomer of mequitazine, an existing oral racemic antihistamine commercialized for over 30 years. (R)-Mequitazine was found to be an antagonist at muscarinic acetylcholine receptors behaving as an inverse agonist. (R)-Mequitazine was investigated in clinical trials for the treatment of chronic obstructive pulmonary disease, asthma and urinary incontinence.