The cost of insurance copayments for cutting-edge pharmaceuticals can vary widely from patient to patient. When the patient’s share of prescription costs becomes too high, many patients skip doses or stop taking medication entirely, according to new research.
Using data from health plan claims for the anticancer drug imatinib filed between 2002 and 2011, Stacie B. Dusetzina, PhD, of the University of North Carolina School of Medicine in Chapel Hill, found that patients with higher copayments were 70% more likely to stop taking their cancer treatment and 42% more likely to skip doses. The study, published by the Journal of Clinical Oncology (2013; doi:10.1200/JCO.2013.52.9123), is one of the first to examine the effect of high out-of-pocket drug costs for targeted cancer therapies on patients.
The research team used health plan claims from privately insured adult patients (age 18 to 64 years) from 2002 to 2011 to examine the relationship between out-of-pocket costs for imatinib (Gleevec) and patient adherence. The data showed that insurance copayments for imatinib ranged from nothing to $4,792 for a 30-day supply of the medicine, with the costs increasing over the study years.
Imatinib is one of the major success stories of modern pharmaceutical development. Before the development of the drug, a patient with chronic myeloid leukemia (CML) had a grim prognosis, with only 30% surviving more than 5 years after diagnosis. With the advent of imatinib, the 5-year survival rate rises to 89% so long as patients adhere to the prescribed treatment plan. Evidence suggests that patients missing even 15% of prescribed doses can relapse, as the cancer develops a resistance to the drug.
“Imatinib is an expensive drug, but it is a great example of a drug where there is not a lot of confusion about which patients will benefit. Most patients with CML will benefit. However, [patients] need to take it almost perfectly, and not taking it can have severe medical consequences,” said Dusetzina. “So maximizing adherence is crucial.”
The data used in the study only included patients on employer-based plans. Most persons had low out-of-pocket costs—the most common cost was $30 for a 30-day supply, but copayments and co-insurance amounts required of patients varied substantially.
“We studied people who are part of large employer groups, so their insurance is probably more generous than someone who is buying insurance on a private market that does not have a lot of negotiating power,” said Dusetzina.
The data has implications beyond imatinib. The cost of many new pharmaceuticals for rare conditions can cost insurers and patients more than $100,000 year.
“Our results are particularly relevant for specialty pharmaceutical products, those that cost over $10,000 a month, however, the lessons learned likely relate to any pharmaceutical product that has high out-of-pocket costs,” said Dusetzina. “It is important that we identify strategies to make effective but expensive medications more affordable to patients.”