The goal of this interventional study is to evaluate the effect of standardized patient coaching on treatment adherence among patients taking abemaciclib.

The main question it aims to answer is, whether standardized coaching leads to patients taking abemaciclib much more consistently. Researchers will therefore compare therapy adherence of patients receiving standardized coaching to patients receiving routine care.

Participants will be asked to answer several questionnaires.

Inclusion Criteria:

• Women age 18 or older at time of ICF signature
• Patients with HRpos/HER2neg early breast cancer who are treated with oral, commercially available prescribed abemaciclib in combination with endocrine therapy. Patients can be included if abemaciclib therapy was started no more than 28 days ago
• Patients treated with abemaciclib according to the SmPC and each center´s medical practice
• Informed consent given prior to the starting study activities

Exclusion Criteria:

• Women who are pregnant or lactating
• Patients with contraindications against abemaciclib according to the current SmPC
• Patients who are not eligible for the study due to severe comorbidities, unavailability or any other relevant reason according to the treating physician