Selective Relaxant Binding Agents (SRBAs) are a new class of drug

Drug

A drug, broadly speaking, is any substance that, when absorbed into the body of a living organism, alters normal bodily function. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage.In pharmacology, a...

s that selectively encapsulates and binds neuromuscular blocking agents (NMBAs). The first drug introduction of an SRBA is sugammadex

Sugammadex

Sugammadex is an agent for reversal of neuromuscular blockade by the agent rocuronium in general anaesthesia. It is the first selective relaxant binding agent and was discovered at the Newhouse research site in Scotland. . These scientists who discovered Sugammadex worked for the pharmaceutical...

. Sugammadex is a modified gamma cyclodextrin that specifically encapsulates and binds the aminosteroid NMBAs: rocuronium

Rocuronium

Rocuronium is an aminosteroid non-depolarizing neuromuscular blocker or muscle relaxant used in modern anaesthesia, to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation.Introduced in 1994, rocuronium has...

>vecuronium

Vecuronium

Vecuronium is a muscle relaxant in the category of non-depolarizing blocking agents. Vecuronium bromide is indicated as an adjunct to general anesthesia, to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation...

>>pancuronium

Pancuronium

Pancuronium is a muscle relaxant with various purposes. It is the second of three drugs administered during most lethal injections in the United States.- Mode of action :...

. SRBAs exert a chelating action that effectively terminates an NMBA ability to bind to nicotinic receptors.

Discovery of SRBAs

The discovery of SRBA as a new class of drug is the result of work done by Organon laboratories at the Newhouse research site

Newhouse Research Site

The Newhouse Research Site is a drug research facility situated east of Glasgow in central Scotland. It is located beside the M8 motorway in Newhouse, North Lanarkshire. The site is an early drug discovery research centre with a track record of generating a succession of products in the areas of...

 in Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

. Cyclodextrin

Cyclodextrin

Cyclodextrins are a family of compounds made up of sugar molecules bound together in a ring ....

s were explored as a means to solubilize rocuronium bromide (a steroidal NMBA) in a neutral aqueous solution. Upon creating numerous modified cyclodextrins, one particular molecule

Molecule

A molecule is an electrically neutral group of at least two atoms held together by covalent chemical bonds. Molecules are distinguished from ions by their electrical charge...

was found to possess extremely high affinity for the rocuronium molecule. Originally known as Org25969, it is now generically named sugammadex sodium.