Rechallenge of Elexacaftor/Tezacaftor/Ivacaftor After Skin Rash in Two Pediatric Patients

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have revolutionized care for patients with cystic fibrosis (CF). The triple combination product elexacaftor/tezacaftor/ivacaftor is a highly effective CFTR modulator that is generally well tolerated. However, in clinical trials of pediatric and adult patients, 4% to 12% developed rash after initiation of therapy. Few reports have described approaches to management of this adverse effect. In this report, we describe 2 children with CF who developed a pruritic, maculopapular rash after initiating elexacaftor/tezacaftor/ivacaftor. These patients were successfully rechallenged after rash resolution with a practical titration schedule. ABBREVIATIONS ADR, adverse drug reaction; CF, cystic fibrosis; CFTR, cystic fibrosis transmembrane conductance regulator; ELX/TEZ/IVA, elexacaftor/tezacaftor/ivacaftor; ppFEV1, percent predicted forced expiratory volume in 1 second.