XP-21279 is a
sustained-release
Modified-release dosage is a mechanism that (in contrast to immediate-release dosage) delivers a drug with a delay after its administration (delayed-release dosage) or for a prolonged period of time (extended-release R, XR, XLdosage) or to a sp ...
levodopa
-DOPA, also known as levodopa and -3,4-dihydroxyphenylalanine, is an amino acid that is made and used as part of the normal biology of some plants and animals, including humans. Humans, as well as a portion of the other animals that utilize -DOPA ...
(
L-DOPA)
prodrug and hence a
dopamine precursor
Monoamine precursors are precursors of monoamines and monoamine neurotransmitters in the body. The amino acids L-tryptophan and L-5-hydroxytryptophan (5-HTP; oxitriptan) are precursors of serotonin and melatonin, while the amino acids L-phe ...
and
non-selective
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from ''ligare'', which means 'to bind'. In protein-ligand binding, the ligand is usually a mol ...
dopamine receptor agonist
A dopamine agonist (DA) is a compound that activates dopamine receptors. There are two families of dopamine receptors, D2-like and D1-like, and they are all G protein-coupled receptors. D1- and D5-receptors belong to the D1-like family and the ...
which was under development for the treatment of
Parkinson's disease
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...
.
It is taken
by mouth
Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are i ...
.
Pharmacology
The drug is said to add a five-
carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes ...
ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ...
conjugate to levodopa that allows it to be
actively transported by high-capacity
nutrient
A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excr ...
transporter
Transporter may refer to:
* Transporter (vehicles), types of vehicles designed to transport items
* Transporter wagon, a railway car designed to carry another railway car
* Volkswagen Transporter, a model of van
* Transporter bridge, a bridge wh ...
s throughout the entire
gastrointestinal tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans a ...
.
Subsequently, it is rapidly converted into levodopa by
carboxylesterase
The enzyme carboxylesterase (or carboxylic-ester hydrolase, EC 3.1.1.1; systematic name carboxylic-ester hydrolase) catalyzes reactions of the following form:
:a carboxylic ester + H2O \rightleftharpoons an alcohol + a carboxylate
Most enzymes fr ...
s.
Levodopa itself can only be transported by a short section of the
small intestine
The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through t ...
and hence XP-21279 allows more time for levodopa to be
absorbed, in turn resulting in an increased
duration
Duration may refer to:
* The amount of time elapsed between two events
* Duration (music) – an amount of time or a particular time interval, often cited as one of the fundamental aspects of music
* Duration (philosophy) – a theory of time and ...
and possibly reduced fluctuations in dopamine levels between levodopa doses.
Clinical studies
As of June 2015, XP-21279 was in
phase 2
Michael Lawrence Marrow (August 2, 1955 – December 12, 2019), known as PHASE 2 and Lonny Wood, was an American aerosol paint artist based in New York City. Mostly active in the 1970s, Phase 2 is generally credited with originating the "bubble ...
clinical trial
Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...
s.
As of May 2022, there have been no further developmental updates.
It was reported in 2018 that development of the drug had been discontinued several years prior.
A 2019 review reported that results were conflicting in phase 2 trials and that this likely resulted in the discontinuation of the drug's development.
Chemistry
Many sources do not report the
chemical structure
A chemical structure determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid. Molecular geometry refers to the spatial arrangement of a ...
of XP-21279, suggesting that its exact structure has not been disclosed.
However, one source appears to report its chemical structure.
See also
*
Etilevodopa
*
Foslevodopa
*
Melevodopa
References
{{Phenethylamines
Abandoned drugs
Antiparkinsonian agents
Benzoate esters
Catecholamines
Dopamine agonists
Esters
Monoamine precursors
Prodrugs