CF patient-derived human bronchial epithelial (HBE) cells; increased CFTR processing and chloride transport
“Alone and in combination with tezacaftor and ivacaftor, elexacaftor facilitates processing and trafficking of CFTR leading to increased chloride transport in HBE cells collected from CF patients.”
✓ VerifiedFDA multi-discipline review, p. 34Source ↗
Why that model
No validated animal model of CF; drugs act specifically on mutant human CFTR
“There is no validated animal model for CF that fully mimics the human multi organ affected disease. Furthermore, the proposed treatment is specific for mutated CFTR proteins.”
EMA: in vitro-only pharmacology acceptable given no validated CF animal model
“As there is no validated animal model for CF that fully mimics the human multi organ affected disease and all three components bind specifically to CFTR, the use of in vitro systems to study the pharmacology of elexacaftor only or in combination with tezacaftor and ivacaftor can be accepted.”