Stefano Giuffrida
FPC4 – Stefano Giuffrida
University of Palermo, Department of biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), Palermo; Italy
stefano.giuffrida@unipa.it
| New insights into PP structural features as class 3 CFTR correctors for combinatorial treatments in cystic fibrosis |
| Stefano Giuffrida1, Marilia Barreca1, Mario Renda2, Fabiana Lo Mascolo1, Alessandra Lipani2, Roberta Bivacqua1, Daniela Guidone2, Michele Genovese2, Maria Valeria Raimondi1, Virginia Spanò1, Alessandra Montalbano1, Fabio Bertozzi3, Tiziano Bandiera3, Francesco Ortuso,4 Stefano Alcaro,4 Luis Juan Vicente Galietta2, and Paola Barraja1 1 University of Palermo, Department of biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), Palermo; Italy 1 Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli (NA); Italy 1 Istituto Italiano di Tecnologia (IIT), Genova, Italy 1 Magna Graecia University, Department of Health Sciences, Catanzaro; Italy |
| Abstract Cystic fibrosis (CF) is a genetic disease caused by mutations that impair the function of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride channel. This defect can be overcome by CFTR “correctors”, small molecule modulators that stabilize the misfolded protein and increase membrane expression [1-3]. Significant progresses have been made in the pharmacological treatment of CF with the development of Kaftrio, a triple combination of two correctors (VX-661, VX-445) and one potentiator (VX-770) and, recently, of Alyftrek, a combination of deutivacaftor, VX-661 and vanzacaftor [4]. However, the development of new CFTR modulators is an important goal to maximize mutant CFTR rescue. In the course of our studies, we have identified a new class of small molecules (called PP compounds) as correctors with high efficacy in the rescue of F508del-CFTR on native epithelial cells of CF patients, particularly in combination with class 1 correctors (VX-809) [5]. A multiparametric optimization of PP compounds is ongoing. In parallel, we are also investigating another family of correctors, called SH compounds, derived from PP compounds using a scaffold hopping approach. These compounds bearing a higher conformational flexibility and offering multiple regions for structural diversification allow the generation of a wide family of analogues with higher optimization potential. The new compounds are tested using the HS-YFP functional assay on CFBE41o- cells expressing F508del-CFTR mutation. The most active compounds are then validated: i) in short-circuit recordings on primary airway epithelial cells; ii) in biochemical assays to evaluate CFTR maturation/trafficking. So far, we have evaluated 450 compounds from which several effective derivatives emerged with EC50 values at sub-micromolar level. Mechanistic studies have shown that PP and SH compounds act as class 3 correctors, able to produce a strong synergistic/additive effect when combined with class 1 agents such as VX-809 and VX-661. Selected candidates were also evaluated for their in vivo pharmacokinetic profile in rodents to preliminary asses their drug-like profile. We have also tested the efficacy and potency of two selected compounds, PP028 and SH157A, when combined with another type of class 1 correctors [6]. In particular, combination of ARN22081, ARN22151, or ARN22361 class 1 correctors with single digit nanomolar potency with PP028 or SH157A markedly enhanced F508del-CFTR rescue. Interestingly, the use of PP028/SH157A produced an increase of the potency of ARN correctors, with a shift of the EC50 values to the sub-nanomolar range. These results confirm the ability of the PP and SH compounds to synergize with ARN correctors thus indicating the possibility to develop novel pharmacological combinations to rescue mutant CFTR. |
| References [1] Elborn, J.S. Lancet (2016) 388, 2519–2531. [2] Stoltz, D.A.D.; Meyerholz, K.; Welsh, M.J. N. Engl. J. Med. (2015) 372, 351–362 [3] Farinha, C.M.; et al. Chem. Biol. (2013) 20, 943–955 [4] Keating, C.; et al., Lancet Respir. Med. (2025) 13, 256–271 [5] Renda, M.; et al. Sci Rep (2023) 13:7604 [6] Pedemonte, N.; et al. (2020) Sci Adv 6:eaay9669 |