Medicare plans limit access to treatments for C. difficile infection
Medicare beneficiaries have limited access to recommended treatments for Clostridioides difficile infection, researchers reported in Clinical Infectious Diseases.
In June, the Infectious Diseases Society of America and Society for Healthcare Epidemiology of America published updated guidelines for managing C. difficile infection (CDI), which included a recommendation to use fidaxomicin over oral vancomycin for CDI.
Previously, both therapies were recommended as first-line options, said Deanna Buehrle, PharmD, an infectious disease clinical pharmacist for the VA Pittsburgh Health Care System.
“We knew from clinical experience that patients often had difficulty accessing these medications due to cost barriers,” Buehrle told Healio. “However, it is not clear how many Americans have these drugs on their prescription drug plan formularies and if plans impose additional barriers such as placement of drugs on high-cost tiers or prior authorization requirements.”
For their study, Buehrle and Cornelius (Neil) J. Clancy, MD, associate professor of medicine and director of the extensively drug-resistant pathogen lab and mycology program at the University of Pittsburgh, used publicly available Medicare prescription drug formulary and enrollment data to characterize the accessibility of fidaxomicin and vancomycin at the time of the 2021 guideline update.
Because elderly patients are at an increased risk for CDI, Medicare data are representative of patients using these medications, according to Buehrle, who said Medicare policy often serves as a standard that is adopted by private insurances.
Overall, they found that although most Medicare enrollees had oral vancomycin (100% of enrollees) and fidaxomicin (approximately 84% of enrollees) on their prescription drug formulary, the therapies were broadly accessible — defined by Buehrle and Clancy as “a formulary agent, unrestricted, and tier 1 or 2” — to only 14.4% of beneficiaries for vancomycin and 1.1% for fidaxomicin.
Around 75% of enrollees had unrestricted formulary access to both drugs, meaning that their plan did not require a prior authorization or step therapy, which can be barriers to filling prescriptions, they said.
Vancomycin and fidaxomicin were on high-cost tiers for almost all enrollees, which determines the corresponding copayment or coinsurance amount that the patient is responsible for.
“To put this into perspective,” Buehrle explained, “a different study of Medicare plans found that the average copayment for tier 4 medications was $100 and the median coinsurance for tier 5 medications was 31% of the drug cost.”
She said the corresponding costs may be unaffordable to many Americans.
“Fidaxomicin and oral vancomycin are broadly accessible ... to very few Medicare enrollees,” Buehrle said. “Clinicians should be aware of these findings and should verify that patients are able to access these medications. This may require use of multidisciplinary teams that can verify insurance coverage of prescriptions, navigate requirements such as prior authorizations, and ensure patients' ability to afford copayments.”