XP-21279

XP-21279 is a sustained-release levodopa prodrug and hence a dopamine precursor and non-selective dopamine receptor agonist which was under development for the treatment of Parkinson's disease. It is taken by mouth.

Pharmacology

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. Subsequently, it is rapidly converted into levodopa by carboxylesterases. 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.

Clinical studies

As of June 2015, XP-21279 was in phase 2 clinical trials. 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 of XP-21279, suggesting that its exact structure has not been disclosed. However, one source appears to report its chemical structure.