Women with early-stage breast cancer who used generic aromatase inhibitors appeared more likely to continue and adhere to their hormone therapy regimens than women who used brand-name agents with higher co-payments, according to study results.
Dawn L. Hershman, MD, MS, associate professor of medicine at Columbia University Medical Center, and colleagues obtained pharmacy and claims data from OptumInsight to identify 5,511 women aged older than 50 years who used aromatase inhibitors for early-stage breast cancer between Jan. 1, 2007, and Dec. 31, 2012.
The analysis included 2,815 (51.1%) women who used brand-name aromatase inhibitors, 1,411 (25.6%) who used generics, and 1,285 (23.3%) who switched from brand-name agents to generics.
Researchers determined median 30-day copayments were $33.30 for women who used brand-name aromatase inhibitors and $9.04 for those who used generics.
Multivariable Cox proportional hazard analysis showed women who used generics were less likely to discontinue therapy (HR=0.69; 95% CI, 0.57-0.84). Women with monthly co-payments of more than $30 (HR=1.49; 95% CI, 1.23-1.8), as well as those with monthly co-payments between $15 and $30 (HR=1.21; 95% CI, 1.01-1.44), were more likely to discontinue treatment than women whose monthly copayments were less than $15.
Multivariable logistic regression analysis showed therapy adherence was positively associated with the use of generic aromatase inhibitors (OR=1.53; 95% CI, 1.22-1.91) and inversely associated with an increased monthly copayment. Results also showed women with an annual income of more than $100,000 per year were more likely to adhere to hormonal therapy (OR=1.58; 95% CI, 1.17-2.11) than those with lower incomes.
“After controlling for copayment, discontinuation was higher and adherence was lower with brand-name aromatase inhibitors,” Hershman and colleagues wrote. “Since previous studies have shown that poor adherence and early discontinuation of hormonal therapy are associated with worse survival, public health efforts … should be directed toward increased drug price transparency, improving access and reducing out-of-pocket costs for life-saving cancer treatments.”
Disclosure: The researchers report no relevant financial disclosures.