Potential New Cystic Fibrosis Treatment Could Raise Costs
San Diego—New drugs on the horizon for cystic fibrosis (CF) could result in better patient outcomes, but will likely come at a higher cost, according to a poster session at AMCP titled Cystic Fibrosis Prevalence and Total Cost of Care in a Commercially Insured Population.
Approved in 2012, ivacaftor is a new cystic fibrosis medication that works by increasing the activity of defective cystic fibrosis transmembrane conductance regulator (CFTR) protein. It is primarily used in a small percentage of CF patients who have rare, specific gene mutations—at a cost of over $300,000 a year.
In November 2014, the FDA received an application to extend use of the drug—specifically, the use of ivacaftor and lumacaftor to treat patients ≥12 years of age who have the F508del homozygous genotype. Note: This specific genotype is found in nearly half of CF patients.
In light of this information, researchers designed a study to learn more about the prevalence of CF, the total pharmacy and medical claims expenses for CF patients, and the potential impact that the combina- tion of ivacaftor and lumacaftor could have on the insured population, if approved.
For the study, researchers used claims data from commercially insured members in 11 health plans who were continuously enrolled in a plan from April 2013 to September 2014. Patients were included if they had ≥2 medical claims with a CF diagnosis code at least 30 days apart.
Researchers divided the patients into 5 different groups: (1) individuals with lung transplantation claims during the study year; (2) those who had a prior lung transplantation; (3) those who were already taking ivacaftor before the study began and were therefore categorized as continuing the medication; (4) those starting ivacaftor during the study period; and (5) all other CF patients.
Researchers found that out of 8,452,368 members who had continuous enrollment during the study period, 1067 were designated as having CF—a prevalence rate of 12.6 per 100,000 members.
Furthermore, researchers found that 6.2% of CF patients previously had a lung transplant and another 0.7% underwent the surgery during the study period. In addition, 3.4% of CF patients had a claim for ivacaftor, with most of these patients (n=31) categorized as continuing therapy patients.
Of the 5 different study groups, the highest costs (mean of $576,776) were associated with individuals who had a lung transplant during the study period. Patients continuing on ivacaftor had the second highest costs, with a total mean cost of $367,427. Patients classified in the “all other CF patients” group had the lowest total mean cost of $76,433.
When researchers looked at CF patients based on age to determine who may be impacted by the possible FDA approval for the combination therapy, they found that 9.6 per 100,000 members had CF and were ≥12 years of age. Researchers estimated that 4.5 per 100,000 members would have the F508del homozygous genotype, and would therefore meet the age and genotype criteria for the new combination therapy.
It is still unknown how much the ivacaftor and lumacaftor combination drug would cost. However, researchers used the $300,000 figure associated with ivacaftor to determine that if 90% of those who met the age and genotype criteria went on to use the ivacaftor and lumacaftor combination, the incremental pharmacy cost for this insured population would be $1.01 per member per month.
The incremental cost could vary based on the actual price of the medication and adherence.
Researchers also listed several limitations, including that the study was not designed to assess whether there were offsetting claims cost savings associated with ivacaftor therapy and the study parameters that were limited to only include continuously enrolled members.—Jill Sederstrom
This study was funded by Prime Therapeutics, LLC.
