Generic Medications Boost Adherence to Breast Cancer Therapy

Although oral hormonal therapy is known to substantially reduce breast cancer recurrence in women with hormone receptor - positive tumors, about one-half of patients fail to take their medications as directed. A study by Columbia University Medical Center (CUMC) researchers has found that the introduction of generic aromatase inhibitors (the most common type of hormone therapy), which are considerably less expensive than their brand-name counterparts, increased treatment adherence by 50 percent.

The study was published today in the online issue of Journal of the National Cancer Institute.

“Our findings suggest that more effort should be made to reduce out-of-pocket costs for these potentially life-saving medications. This is especially important given the rapid increase of expensive oral cancer therapies,” said study leader Dawn L. Hershman, MD, MS, associate professor of medicine at the College of Physicians and Surgeons, and associate professor of epidemiology at the Mailman School of Public Health, Columbia University Medical Center. Dr. Hershman is also leader of the Breast Cancer Program at the Herbert Irving Comprehensive Cancer Center at NewYork-Presbyterian/Columbia University Medical Center.

“We know that hormone therapy for women with hormone receptor - positive breast cancer can reduce recurrence by up to 50 percent,” said Dr. Hershman.“However, work by our group and others has shown that a substantial number of women discontinue treatment before the recommended five years or do not take the prescribed dose.

This is increasingly important because we are starting to learn that even longer therapy - up to 10 years - may be beneficial. It’s critical that we understand why people do not take their medication and what we can do to improve adherence."

In a previous study, Dr. Hershman and her colleagues found that higher co-payments for aromatase inhibitors (AIs) significantly decreased adherence to therapy. "When AIs were released in generic form in 2010, we had a unique opportunity to study whether a reduction in overall medication cost would make a difference in adherence," she said. To find out, the researchers examined the pharmacy records of 5,511 women ages 50 or older with early-stage breast cancer (requiring lumpectomy or mastectomy) who were prescribed hormonal therapy fromn 2007-12. Each patient was followed for 24 months.

The researchers found that women taking generic AIs were more 50 percent more likely to take the medications on schedule and 30 percent less likely to discontinue therapy early, compared with women taking brand name AIs. Among women on brand name generics, 33 percent discontinued therapy, compared with just 16 percent on generics.

As monthly out-of-pocket co-payments increased, adherence rates decreased. Even a small increase in monthly co-payments, from less than $15 to $15 to $30, resulted in a significant decrease in adherence," said Dr. Hershman. "That might not seem like a lot money, but it can be a big expense if you multiply it over five or ten years and you have other prescriptions to pay for."