Compliance and arthralgias in clinical therapy (COMPACT): Assessment of the incidence of arthralgia, therapy costs, and compliance in the first year of adjuvant anastrozole.

e11040^ Background: Aromatase Inhibitors (AI) are well established as adjuvant endocrine treatment for postmenopausal women with HR+ early breast cancer (EBC). However, clinical trial data show higher frequently of arthralgia with AI than tamoxifen. As arthralgia may be greatly influencing compliance to adjuvant therapy, we designed a prospective trial to collect real world data on the effects of AI-associated arthralgia on patient compliance, patient outcomes and treatment costs of arthralgia. Methods: COMPACT is an open, prospective non-interventional study (NCT00857012) assessing the incidence of arthralgia, therapy costs, and compliance within the first year of adjuvant anastrozole (AN…