In a virtual symposium held in conjunction with the Asembia Specialty Pharmacy Summit, 2 speakers covered the numerous care improvements developed for cystic fibrosis over the past 10 to 20 years.
CYSTIC FIBROSIS (CF) is an inherited autosomal recessive disease, and it affects approximately 30,000 Americans. Chronic, progressive, and life-shortening, CF primarily targets the lungs and the pancreas, but can also affect the gastrointestinal tract, reproductive organs, and sinuses. In a virtual symposium held in conjunction with the Asembia Specialty Pharmacy Summit, 2 speakers covered the numerous care improvements developed for CF over the past 10 to 20 years.
Rachel Espinosa, PharmD, described a defect in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CFTR maintains fluid balance across epithelial cells, but in CF, decreased chloride transport leads to dehydration and thick secretions. Impaired pulmonary mucociliary clearance and obstruction, destruction, or scarring in the pancreas are also problematic. Field experts have described multiple main classes of mutations, each with its own unique patterns; the most common mutation is F508 deletion (del).
Espinosa indicated that historically, a diagnosis of CF was based on symptoms such as persistent cough, salty skin, failure to thrive, frequent lung infection, and oily or greasy stool. Today, most diagnoses occur at birth, as all 50 states now perform newborn screening. The sweat test is a helpful diagnostic tool that measures the amount of chloride; patients that test positive are then evaluated by a center accredited by the Cystic Fibrosis Foundation (CFF).
While lung function is expected to decrease over time, the goal of treatment is to arrest the natural disease progression. Pharmacists play a critical role because patients often need antibiotics for pulmonary exacerbations. Patients with CF also have altered clearance and larger volumes of distribution than other patients, so expertise with pharmacokinetic monitoring is needed. In addition, pharmacists help patients manage exocrine pancreatic insufficiency and can consult on other medications including anti-inflammatories and inhaled therapies.
The new CFTR modulators have changed CF’s trajectory, correcting the underlying CFTR channel defect and improving pulmonary outcomes. Dr Espinosa reviewed ivacaftor, lumacaftor, tezacaftor, and elexacaftor (and combinations) including expanding indications and a summary of safety and efficacy. Elexacaftor was approved as part of a triple combination therapy at the end of 2019 and is indicated for patients 12 years and older with an F508del mutation, which is estimated to affect approximately 90% of the CF population.
Emily Stephan, PharmD, focused on the role of specialty pharmacists and discussed the necessity of using a multidisciplinary team to address CF. Specialty pharmacists recommend therapy adjustments, inform the team about adherence concerns, and collaborate to overcome access issues. The CFF requires a set of 6 specific disciplines on each CF team, but they also recommend including pharmacists. Pharmacists within the CF community are working toward being considered essential members of the CF team.
Patient counseling is critical because patients who have CF take many medications, and each medication has specific requirements. For example, patients need to take pancreatic enzymes before they eat or they will not absorb their food or fat-soluble vitamins. Stephan also reviewed basic counseling points for inhaled medications, including mucolytics such as dornase alfa and antibiotics. She also expanded on the CFTR modulators, including discussion of dosing, administration (taking with fat-containing foods), adverse effects, and potential drug interactions, particularly with CYP3A inducers.
Adherence is a significant concern among patients who have CF because medication burden is high. Pharmacists need to conduct adherence assessments, looking carefully for missed doses, tracking patient medication counts when possible, and using motivational interviewing to determine what the patient’s goals are. Ensuring patients know the purpose of each medication helps them understand why adherence is important. Some other mechanisms that can improve adherence are reducing treatment burden, reducing access barriers, and referring patients for psychosocial interventions.