Respiratory Outcomes of Interrupted Modulator Therapies in Children with
Cystic Fibrosis
Abstract
Background Cystic fibrosis (CF) is a multisystemic disease
caused by mutations in the cystic fibrosis transmembrane conductance
regulator ( CFTR) gene, resulting in defective synthesis or
function of the CFTR protein. Historically, CF treatment focused on
managing symptoms and complications. Fortunately, modulator drugs are
now available to directly target the defective CFTR protein. However, in
some countries, such as Turkey, these drugs are not covered by social
insurance. Consequently, many CF patients face barriers to accessing
modulatory therapies or must interrupt their treatment. This study
demonstrates the impact of interrupting modulator therapy on pulmonary
function, emphasizing the need for uninterrupted continuous treatment.
Methods In this study, 39 CF patients receiving
elexacaftor-tezacaftor-ivacaftor (ETI) at our clinic were
retrospectively analyzed. Among the patients, 18 experienced one or more
interruptions, ranging from 15 to 210 days during ETI treatment. We
analyzed pulmonary function test results from 27 interruption periods.
Results At the beginning of the interruption, the mean percent
predicted FEV1 (ppFEV1) was 69.59 ± 25.87%, which decreased to 64.96 ±
24.52% by the end of the interruption. There was a significant decrease
with a mean change of 4.62 ± 8.49 (p = 0.008). However, no significant
correlation was found between the interruption duration and FEV1 change.
Conclusion Our results demonstrate that pulmonary functions are
adversely affected by interruption periods, regardless of their
duration. Even short interruptions have a significant impact on
pulmonary functions. This underscores the need for uninterrupted
continuation of modulatory treatment and for improved policies to ensure
equitable access to treatment.