ER+/HER2- breast cancer: Is first or second line CDK4/6 inhibitor therapy better?

The article focuses on a study conducted by researcher Gabe Sonke and colleagues which found that advanced estrogen receptor-positive, human epidermal growth factor (HER)-negative breast cancer patients who received CDK4/6 inhibitors as first-line therapy did not outlive those who received the same as second-line therapy in terms of progression-free survival (PFS) or overall survival (OS). It states that in both the first and second-line applications, CDK4/6 have demonstrated efficacy.