New Tic Disorder in a Child With Cystic Fibrosis Treated With Elexacaftor/Tezacaftor/Ivacaftor

The widespread use of highly effective cystic fibrosis transmembrane-conductance regulator -modulator therapy has dramatically altered the lives of individuals with cystic fibrosis. Clinical trials leading to -modulator approval by the US Food and Drug Administration demonstrated improvements in major -outcome measures including pulmonary function, gastrointestinal symptoms, and quality of life. Subsequent clinical experience has confirmed significant improvement across these domains. Adverse effects reported -during clinical trials included headache and dizziness amongst others including upper respiratory infections, abdominal pain, diarrhea, rash, and elevated serum transaminases. Post marketing clinical experience has suggested that there may be additional central nervous system adverse effects resulting from modulator therapy. Reported events after initiation of cystic fibrosis transmembrane-conductance regulator modulator treatment include headaches and increased prevalence of mental health concerns including anxiety and depression. We report a new tic disorder in a 7-year-old girl with cystic fibrosis treated with elexacaftor/tezacaftor/ivacaftor.

Changes in fecal elastase-1 following initiation of CFTR modulator therapy in pediatric patients with cystic fibrosis

BACKGROUND

Improvement in exocrine pancreatic function in persons with CF (pwCF) on cystic fibrosis transmembrane conductance regulator (CFTR) modulators has been documented in clinical trials using fecal pancreatic elastase-1 (FE-1). Our group endeavored to evaluate real-world data on FE-1 in children on CFTR modulator therapy at three pediatric cystic fibrosis (CF) centers.

METHODS

Pediatric pwCF were offered FE-1 testing if they were on pancreatic enzyme replacement therapy (PERT) and on CFTR modulator therapy according to their center's guideline. FE-1 data were collected retrospectively. The primary outcome was absolute change in FE-1.

RESULTS

70 pwCF were included for analysis. 53 had baseline and post-modulator FE-1 values. There was a significant increase in FE-1 from median 25 mcg/g (IQR 25-60) at baseline to 57 mcg/g (IQR 20-228) post-modulator (p<0.001 by Wilcoxon matched pairs), with an absolute change in FE-1 of median 28 mcg/g (IQR -5-161) and mean 93.5 ± 146.8 mcg/g. Age was negatively correlated with change in FE-1 (Spearman r=-0.48, p<0.001). 15 pwCF (21%) had post-modulator FE-1 values ≥200 mcg/g, consistent with pancreatic sufficiency (PS). The PS group was significant for younger age at initiation of first CFTR modulator and a higher baseline FE-1.

CONCLUSIONS

Most pwCF experienced an increase in FE-1 while receiving CFTR modulator treatment and a small percentage demonstrated values reflective of PS. These data suggest that PS may be attained in those that initiated modulator therapy at a younger age or had a higher baseline FE-1. FE-1 testing is suggested for children on any CFTR modulator therapy.