Aromatase Inhibitors

This prospective, response-adapted phase II study evaluates the efficacy and safety of neoadjuvant culmerciclib in combination with aromatase inhibitors in patients with highly proliferative ER-positive/HER2-negative breast cancer. All patients initially receive induction treatment with culmerciclib plus endocrine therapy, followed by on-treatment assessment of biological and clinical response. Patients demonstrating an adequate response continue the same regimen, whereas those with a suboptimal response are transitioned to alternative treatment strategies prior to surgery. This adaptive approach aims to optimize treatment selection, improve therapeutic efficacy, and avoid unnecessary exposure to ineffective therapy.

This prospective, response-adapted phase II study evaluates the efficacy and safety of neoadjuvant fovinaciclib in combination with aromatase inhibitors and dual HER2 blockade in patients with HR-positive/HER2-positive early breast cancer. All patients initially receive induction treatment with fovinaciclib plus endocrine therapy and HER2-targeted therapy, followed by early assessment of treatment response after 6 weeks of treatment. Patients demonstrating an adequate response continue the same regimen, whereas those with a suboptimal response are transitioned to standard neoadjuvant chemotherapy combined with HER2-targeted therapy prior to surgery. This adaptive approach aims to optimize treatment selection, improve therapeutic efficacy, and reduce unnecessary chemotherapy exposure.