Switching CDK4/6 inhibitors to overcome toxicity in HR-positive/HER2-negative advanced breast cancer

An international observational study of 1,413 patients with HR+ HER2- advanced breast cancer evaluated the safety, feasibility, and clinical effects of switching CDK4/6 inhibitors due to toxicity. Of the 67 patients who switched CDK4/6 inhibitors, recurrence of the same toxicity occurred in 30% of patients, and only 7 patients who switched ultimately required permanent discontinuation of the second CDK4/6 inhibitor for toxicity. The investigators concluded that switching CDK 4/6 inhibitors may be a promising strategy to avoid treatment interruption.