RESUMO
Pimavanserin is a selective 5-HT2A receptor inverse agonist approved by FDA on April 29, 2016, and it is the first drug for the treatment of hallucinations and delusions associated with Parkinson' s disease. Pimavanserin is with high safety, good toleration and promising clinical efficiency, which is a timely option to resolve the drug shortage in clinic treatment. This paper summarized its pharmacodynamics, pharmacokinetics, clinical studies, adverse reactions and drug interactions.
RESUMO
Inverse agonist is a new type of drug acting on receptors.Its research has experienced several stages, including discovery of ethylβ-carboline 3-carboxylate,activity study,proposal of the concept,two-state model,and constitutive activity theory in succession.Most G protein-coupled receptors possess constitutive activity,i.e.a proportion of receptors are in active state and can produce effects without any agonist.Inverse agonist has an affinity to receptors,but no intrinsic activity,so it cannot activate receptors.However,it can antagonize the constitutive activity of receptors,and produce an opposite effect on the corresponding agonist.Both agonist and inverse agonist can produce their effect alone with different mechanisms.Agonist activates its receptors,but inverse agonist antagonizes them.Both inverse agonist and antagonist can antagonize receptors.However,inverse agonist and antagonist antagonize the constitutive activity of receptor and the agonist’s effects,respectively.Inverse agonists can be used to treat diseases with enhanced constitutive activity,up-regulate and sensitize receptors with constitutive activity.Moreover,endogenous inverse agonists can maintain a specific physiological function.The study on inverse agonist has a theoretical significance in perfecting receptor theory as well as a clinical value in diagnosis and treatment of diseases with enhanced constitutive activity.
RESUMO
Inverse agonist is a new type of classification.Different form antagonist that blocks the effect of agonist,inverse agonist produces opposite effect to that of agonist.The characteristics of inverse agonists acting on different receptors including H_2,H_3,? opioid,adrenergic ?, and 5-HT_((1B)) receptors are discussed in this paper.Recent investigation suggested that inverse agonist has potential clinical application.