Key clinical point: One year of palbociclib added to endocrine therapy after neoadjuvant chemotherapy did not improve invasive disease-free survival when compared with placebo plus endocrine therapy in women with hormone receptor–positive, HER2-negative primary breast cancer.

Major finding: The 4-year invasive disease-free survival rate was 73.0% for palbociclib and 72.4% for placebo (hazard ratio, 0.93; P = .525).

Study details: A phase 3 trial of 1,250 women with hormone receptor–positive, HER2-negative primary breast cancer who were at high risk of relapse after neoadjuvant chemotherapy.

Disclosures: The trial was sponsored by the German Breast Group in collaboration with Pfizer, the AGO Study Group, NSABP Foundation, and the Breast International Group. Dr. Loibl disclosed grant and other support from Pfizer during the conduct of the study, relationships with other companies outside the submitted work, a pending patent for a method to predict response to anti-HER2–containing therapy and/or chemotherapy, and a relationship with Medscape, which is owned by the same company as MDedge.