Opportunity for pharmacogenomic testing in patients with cystic fibrosis

Abstract

Background Patients with cystic fibrosis (CF) are exposed to many drugs in their lifetime and many of these drugs have Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines that are available to guide dosing. Contemporary CF treatments are targeted to specific mutations in the CF transmembrane conductance regulator (CFTR) gene, and thus, require patients to have genetic testing before initiation of modulator therapy. However, aside from CFTR genetic testing, pharmacogenomic testing is not standard of care for CF patients. Aim The aim of this study is to determine the number of non-CFTR modulator medications with CPIC guidelines that are prescribed to patients with CF. Materials & Methods We identified all patients with a diagnosis of CF and queried our hospital electronic medical records (EMR) for all orders, including inpatient and prescriptions, for all drugs or drug classes that have CPIC actionable guidelines for drug–gene pairs that can be used to guide therapy. Results We identified 576 patients with a diagnosis of CF that were treated at our institution during this 16-year period between June 2005 and May 2021. Of these patients, 504 patients (87.5%) received at least one drug that could have been dosed according to CPIC guidelines if pharmacogenomic results would have been available. Conclusions Patients with CF have high utilization of drugs with CPIC guidelines, therefore preemptive pharmacogenomic testing should be considered in CF patients at the time of CFTR genetic testing.