CFTR and cystic fibrosis: Olivier et al. (2023) observed, in their study on CF patients receiving various CFTR modulators, that the mean sweat chloride concentration decreased by 59.3 mmol/L with ELX/TEZ/IVA and by 47.8 mmol/L in those transitioning from IVA/LUM or TEZ/IVA to ELX/TEZ/IVA [89].