Impact of CFTR-modulating drugs on GH-IGF-1 axis impairment in adult patients with cystic fibrosis.

Introduction A new class of drugs in the treatment of cystic fibrosis (CF) includes two agents: lumacaftor, which corrects CFTR channel protein, and ivacaftor, which increases CFTR channel activity. In our previous study we recruited 50 stable adults with CF and 16 of them showed growth hormone deficit (GHD): 7 patients severe and 9 patients partial GHD. Material and methods We decided to re-evaluate ten patients with the GHRH + arginine test of whom only five were treated with lumacaftor/ivacaftor. Results All CF patients in therapy with lumacaftor/ivacaftor showed a marked improvement in GHD. Two patients moved from a severe GHD to a normal response to the GH/IGF-1 axis test, and three patients who had partial GHD moved to normal response. Conclusion The pituitary gland may be damaged by CF disease and could benefit of the action of correcting drugs.