Fatty acid acylated peptide therapeutics: discovery of omega-n oxidation of the lipid chain as a novel metabolic pathway in preclinical species.

We recently described C18 fatty acid acylated peptides as a new class of potent long-lasting single-chain RXFP1 agonists that displayed relaxin-like activities in vivo. Early pharmacokinetics and toxicological studies of these stearic acid acylated peptides revealed a relevant oxidative metabolism occurring in dog and minipig, and also seen at a lower extent in monkey and rat. Mass spectrometry combined to NMR spectroscopy studies revealed that the oxidation occurred, unexpectedly, on the stearic acid chain at ω-1, ω-2 and ω-3 positions.

Effect of deuteration on the metabolism and clearance of some pharmacologically active compounds--synthesis and in vitro metabolism of deuterated derivatives of dronedadrone.

The synthesis and in vitro metabolism studies of a family of specifically deuterated derivatives of dronedarone are described. Metabolic stability and clearance of the parent compound are not sensitive to deuterium substitution, irrespective of the position of the heavy label.

An improved method for specific and quantitative determination of the clopidogrel active metabolite isomers in human plasma.

Pharmacokinetic analyses of clopidogrel are hampered by the existence of multiple active metabolite isomers (H1 to H4) and their instability in blood. We sought to retest the pharmacodynamic activities of the four individual active metabolite isomers in vitro, with the ultimate aim of determining the isomers responsible for clopidogrel activity in vivo. In vitro activity was evaluated by measuring binding of [³³P]-2-methylthio-ADP on P2Y₁₂-expressing Chinese hamster ovary (CHO) cells and human platelets in platelet-rich plasma (PRP).