Because cystic fibrosis transmembrane conductance regulator modulator therapies are new, researchers sought to understand patient adherence as well as potential challenges.
Data from patients with cystic fibrosis (CF) who were prescribed CF transmembrane conductance regulator (CFTR) modulator medications found that although there was a positive adherence to the medications, there was also a substantial financial burden on both patients and third-party payers responsible for the medication cost, according to a study by AllianceRx Walgreens Prime.
CF, which caused by changes in the CFTR gene, is a progressive, genetic disease that causes persistent lung infections and limits the ability to breathe over time. In patients with CF, changes in the CFTR gene can disrupt the normal production or functioning of the CFTR protein found in the cells of the lungs and other parts of the body. Since the introduction of the first CFTR modulator in 2012 and subsequent CFTR modulator approvals, these medications have significantly changed the treatment of CF, according to the study.
Because CFTR modulator therapies are new, researchers wanted to understand how patients are adhering to them as well as any potential challenges with the therapy.
For the study, the researchers used prescription refill and patient assessment data from a national specialty pharmacy database. They analyzed data of patients using CFTR modulator therapies, such as ivacaftor, lumacaftor/ivacaftor and tezacaftor/ivacaftor, between September 2017 and August 2018, and calculated adherence using a proportion of days covered (PDC) measurement.
Of the 3482 patients using CFTR modulator therapies, 50.8% of patients were on lumacaftor/ivacaftor, followed by 24.8% on tezacaftor/ivacaftor, and 24.4% on ivacaftor. The PDC values for the CFTR modulator therapies was above 80%, signifying patients were adherent to the newer therapies.
"[These] data indicates patients are maintaining a high level of adherence to the CFTR modulators," said study author Richard T. Miller, MSPharm, MBA, RPh, CSP, vice president of Clinical and Professional services at AllianceRx Walgreens Prime.
"Better adherence may help patients control their CF symptoms, as well as potential disease progression and future healthcare costs," Miller added. He explained that additional studies are necessary to determine the overall benefit of CFTR modulators on controlling the disease and improving the quality of life for patients with CF.
To understand the trends associated with the use of CFTR modulator therapies, the researchers needed to estimate patients’ drug co-pays. Therefore, the study authors analyzed prescription refills, insurance characteristics, and patient co-pays from January 2015 to August 2018.
During that period, a total of 4444 patients contributed to 57,960 refills of CFTR modulator therapies. Most refills (62%) were for patients with only primary insurance, whereas approximately 37% of refills were for patients with both primary and secondary insurances.
Overall, researchers observed a fluctuation in average monthly patient co-pay with a high of $312.70 (2018) and a low of $182.05 (2016). Researchers noticed an upward trend in the annual spending on lumacaftor/ivacaftor with $67 million in 2015, which increased to $281 million in 2017. However, spending on ivacaftor remained constant over the years with $103 million spent in 2015 and $119 million in 2017.
The study authors noted that there is a need to monitor the characteristics of CF and the impact of co-pays across different insurances and patient outcomes.