Oscar Mammoliti

Progress toward JAK1-selective inhibitors.

The discovery of the JAK-STAT pathway was a landmark in cell biology. The identification of these pathways has changed the landscape of treatment of rheumatoid arthritis and other autoimmune diseases. The two first (unselective) JAK inhibitors have recently been approved by the US FDA for the treatment of myelofibrosis and rheumatoid arthritis and many other JAK inhibitors are currently in clinical development or at the discovery stage. Research groups have demonstrated the different roles of JAK member and the therapeutic potential of targeting them selectively. JAK1 plays a critical and potentially dominant role in the transduction of γc cytokine (γc = common γ chain) and in IL-6 signaling. In this review, we will discuss the state-of-the-art research that evokes JAK1 selective inhibition.

Discovery of N-(3-Carbamoyl-5,5,7,7-tetramethyl-5,7-dihydro-4H-thieno[2,3-c]pyran-2-yl)-lH-pyrazole-5-carboxamide (GLPG1837), a Novel Potentiator Which Can Open Class III Mutant Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Channels to a High Extent

Cystic fibrosis (CF) is caused by mutations in the gene for the cystic fibrosis transmembrane conductance regulator (CFTR). With the discovery of Ivacaftor and Orkambi, it has been shown that CFTR function can be partially restored by administering one or more small molecules. These molecules aim at either enhancing the amount of CFTR on the cell surface (correctors) or at improving the gating function of the CFTR channel (potentiators). Here we describe the discovery of a novel potentiator GLPG1837, which shows enhanced efficacy on CFTR mutants harboring class III mutations compared to Ivacaftor, the first marketed potentiator. The optimization of potency, efficacy, and pharmacokinetic profile will be described.

Identification and Characterization of Novel CFTR Potentiators

There is still a high unmet need for the treatment of most patients with cystic fibrosis (CF). The identification and development of new Cystic Fibrosis Transmembrane conductance Regulator (CFTR) modulators is necessary to achieve higher clinical benefit in patients. In this report we describe the characterization of novel potentiators. From a small screening campaign on F508del CFTR, hits were developed leading to the identification of pre-clinical candidates GLPG1837 and GLPG2451, each derived from a distinct chemical series. Both drug candidates enhance WT CFTR activity as well as low temperature or corrector rescued F508del CFTR, and are able to improve channel activity on a series of Class III, IV CFTR mutants. The observed activities in YFP halide assays translated well to primary cells derived from CF lungs when measured using Trans-epithelial clamp circuit (TECC). Both potentiators improve F508del CFTR channel opening in a similar manner, increasing the open time and reducing the closed time of the channel. When evaluating the potentiators in a chronic setting on corrected F508del CFTR, no reduction of channel activity in presence of potentiator was observed. The current work identifies and characterizes novel CFTR potentiators GLPG1837 and GLPG2451, which may offer new therapeutic options for CF patients.