XP-21279

Clinical data
Other names	XP21279
Routes of administration	Oral[1][2][3]
Drug class	Dopamine precursor; Dopamine receptor agonist
Identifiers
IUPAC name [(2R)-1-[(2S)-2-Amino-3-(3,4-dihydroxyphenyl)propanoyl]oxypropan-2-yl] benzoate
CAS Number	1426325-45-2
PubChem CID	11559525
DrugBank	DB06319
ChemSpider	9734299
ChEMBL	ChEMBL4763200
Chemical and physical data
Formula	C19H21NO6
Molar mass	359.378 g·mol−1
3D model (JSmol)	Interactive image
SMILES C[C@H](COC(=O)[C@H](CC1=CC(=C(C=C1)O)O)N)OC(=O)C2=CC=CC=C2
InChI InChI=1S/C19H21NO6/c1-12(26-18(23)14-5-3-2-4-6-14)11-25-19(24)15(20)9-13-7-8-16(21)17(22)10-13/h2-8,10,12,15,21-22H,9,11,20H2,1H3/t12-,15+/m1/s1 Key:AKUWZLYXAADOTQ-DOMZBBRYSA-N

XP-21279 is a sustained-release levodopa (L-DOPA) prodrug and hence a dopamine precursor and non-selective dopamine receptor agonist which was under development for the treatment of Parkinson's disease.^[4][1][3] It is taken by mouth.^[1][2][3]

The drug is said to add a five-carbon ester conjugate to levodopa that allows it to be actively transported by high-capacity nutrient transporters throughout the entire gastrointestinal tract.^[2][3][5] Subsequently, it is rapidly converted into levodopa by carboxylesterases.^[2][3][5] Levodopa itself can only be transported by a short section of the small intestine and hence XP-21279 allows more time for levodopa to be absorbed, in turn resulting in an increased duration and possibly reduced fluctuations in dopamine levels between levodopa doses.^[1][2][3]

As of June 2015, XP-21279 was in phase 2 clinical trials.^[4] As of May 2022, there have been no further developmental updates.^[4] It was reported in 2018 that development of the drug had been discontinued several years prior.^[6] 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.^[5]

Many sources do not report the chemical structure of XP-21279, suggesting that its exact structure has not been disclosed.^{[7][8][9][6][10]} However, one source appears to report its chemical structure.^[11]

• Etilevodopa
• Foslevodopa
• Melevodopa