Can Drug Cost Drive Oral Medication Adherence Up?

Audrey Andrews

July 2012, Vol 3, No 5 - ASCO Annual Meeting


Chicago, IL—Canadian researchers reported a finding at the 2012 American Society of Clinical Oncol ogy meeting that runs contrary to what other researchers have ob served in the majority of studies. In this study, as oral drug costs increased, so did the likelihood of patients adhering to a prescribed regimen.

Low adherence rates have been documented for many oral therapies in various diseases, and medication nonadherence is often the primary cause of treatment failure. “To our knowledge, cost-related adherence to oral therapy in the context of malignancy has not been studied extensively,” said Jalal Ebrahim, MD, of St Michael’s Hospital, University of Toronto, Ontario, Canada.

He and his colleagues conducted a study of 453 patients with cancer at 3 outpatient hematology/oncology clinics. They used a 7-item survey to in – vestigate patient self-reported adherence to oral medication, type of coverage, and patients’ perceived cost of the drugs.

Of the 453 patients, 50% had a private drug plan, 24% paid for the drug out of pocket, 44% had government funding, and 4% said their physician had arranged funding for their medication.

Approximately 50% of the patients had a drug cost of ≥$100 monthly. Patients paying out of pocket were significantly less likely than all other patients to have oral drug costs of ≥$500 monthly (11% vs 19%, respectively). There was also a significant relationship between drug coverage and oral drug costs.

Patients with annual incomes of ≥$70,000 were more likely than those with lower incomes to have monthly drug costs of ≥$1000 (18% vs 9%, respectively). “It is possible that patients are provided with more education regarding newer and more expensive agents than they are for older and cheaper agents, regardless of efficacy,” according to Dr Ebrahim.

Strong Adherence to High-Cost Drugs

“A strong correlation was observed between monthly oral drug cost and adherence to the regimen,” he said.

A low monthly drug cost was not associated with higher adherence rates. The adherence rates related to monthly out-of-pocket costs were:

  • 55% adherence with ≤$10
  • 83% adherence with $10-$100
  • 83% adherence with $100-$500
  • 75% adherence with $500-$1000
  • 85% adherence with ≥$1000.

Dr Ebrahim believes that patients consider more expensive drugs to be more valuable, and therefore should not be wasted. This “designer drug” phenomenon may explain the increased adherence rates that were found to be associated with high-cost drugs.

“Poor communication between physicians and patients can lead to poor adherence. A lack of education regarding older, cheaper medications could be a catalyst for nonadherence,” Dr Ebrahim suggested.

The disparities found in this study in medication costs for patients with private drug plans versus those without private plans suggest that financial restrictions may affect prescription patterns, the team noted.