Human Pharmacokinetics of LYS006, an Oral Leukotriene A4 Hydrolase Inhibitor Displaying Target-Mediated Drug Disposition.

LYS006 is a potent leukotriene A4 hydrolase inhibitor currently in clinical development for long-term treatment of various neutrophil-driven inflammatory conditions. Here, we present pharmacokinetics from the first-in-human study with complementary metabolism and transporter profiling data. The randomized first-in-human study included nine cohorts receiving 5-2*100 mg of LYS006 or placebo, a crossover food-effect part, and a multiple-dose part consisting of two fasted (5 mg and 15 mg once daily) and three fed cohorts (20-80 mg twice a day) of LYS006 or placebo.

A Systematic In Vitro Investigation of the Inhibitor Preincubation Effect on Multiple Classes of Clinically Relevant Transporters.

Preincubation of a drug transporter with its inhibitor in a cell-based assay may result in the apparent enhancement of the inhibitory potency. Currently, limited data are available on potentiation of transporter inhibition by preincubation (PTIP) for clinically relevant solute-carrier transporters other than OATP1B1 and OATP1B3. Therefore, PTIP was examined systematically using OATP1B1, OATP1B3, OAT1, OAT3, OCT1, OCT2, MATE1, and MATE2-K cell lines.

Examining P-gp efflux kinetics guided by the BDDCS - Rational selection of in vitro assay designs and mathematical models.

The generation of reliable kinetic parameters to describe P-glycoprotein (P-gp) activity is essential for predicting the impact of efflux transport on gastrointestinal drug absorption. The compound-specific selection of in vitro assay designs and ensuing data analysis methods is explored in this manuscript. We measured transcellular permeability and cellular uptake of five P-gp substrates in Caco-2 and LLC-PK1 MDR1 cells.

Fragment-Based Protein-Protein Interaction Antagonists of a Viral Dimeric Protease.

Fragment-based drug discovery has shown promise as an approach for challenging targets such as protein-protein interfaces. We developed and applied an activity-based fragment screen against dimeric Kaposi's sarcoma-associated herpesvirus protease (KSHV Pr) using an optimized fluorogenic substrate. Dose-response determination was performed as a confirmation screen, and NMR spectroscopy was used to map fragment inhibitor binding to KSHV Pr.

The paracaspase MALT1 cleaves HOIL1 reducing linear ubiquitination by LUBAC to dampen lymphocyte NF-κB signalling.

Antigen receptor signalling activates the canonical NF-κB pathway via the CARD11/BCL10/MALT1 (CBM) signalosome involving key, yet ill-defined roles for linear ubiquitination. The paracaspase MALT1 cleaves and removes negative checkpoint proteins, amplifying lymphocyte responses in NF-κB activation and in B-cell lymphoma subtypes. To identify new human MALT1 substrates, we compare B cells from the only known living MALT1(mut/mut) patient with healthy MALT1(+/mut) family members using 10-plex Tandem Mass Tag TAILS N-terminal peptide proteomics.

In-cell selectivity profiling of serine protease inhibitors by activity-based proteomics.

Activity-based proteomics is a methodology that is used to quantify the catalytically active subfraction of enzymes present in complex mixtures such as lysates or living cells. To apply this approach for in-cell selectivity profiling of inhibitors of serine proteases, we designed a novel activity-based probe (ABP). This ABP consists of (i) a fluorophosphonate-reactive group, directing the probe toward serine hydrolases or proteases and (ii) an alkyne functionality that can be specifically detected at a later stage with an azide-functionalized reporter group through a Cu(I)-catalyzed coupling reaction ("click chemistry").