“I expect the NATALEE trial results will change clinical practice,” stated ASCO expert Rita Nanda, MD, Director of the Breast Oncology Program at University of Chicago Medicine.

“Three different CDK4/6 inhibitors have all been shown to improve progression-free survival in the first- and second-line advanced cancer setting. Ribociclib and abemaciclib improved overall survival in metastatic breast cancer. All three of these agents have been studied in hormone receptor–positive, HER2-negative early breast cancer. The phase III PALLAS and PENELOPE-B trials of adjuvant palbociclib were negative, and the monarchE trial was positive, but that trial included only node-positive patients,” she explained. “The monarchE trial led to the approval of adjuvant abemaciclib in node-positive patients.”

Rita Nanda, MD

Dr. Nanda continued: “The NATALEE trial showed an early significant reduction in invasive disease–free survival for patients with high-risk, node-positive and node-negative, hormone receptor–positive, HER2-negative early breast cancer. We know that a substantial proportion of these patients can go on to recur, some of them with a delayed recurrence. Up to this point, no CDK4/6 agent has improved outcomes in node-negative early breast cancer.”

In the context of the NATALEE trial, ribociclib was effective and well tolerated, commented Dr. Nanda. “Ribociclib is another option for high-risk, node-positive and node-negative disease, and this will be an important contribution,” she said. 

DISCLOSURE: Dr. Nanda has served as a consultant or advisor to Merck, OncoSec, Cardinal Health, Seattle Genetics, Fujifilm, ITeos Therapeutics, AstraZeneca, Gilead Sciences, Infinity Pharmaceuticals, OBI Pharma, GE Healthcare, Beyond Spring Pharmaceuticals, and Sanofi; and has received research support from Concept Therapeutics, Celgene, Merck, Seattle Genetics, Genentech/Roche, Odonate Therapeutics, Pfizer, AstraZeneca, Immunomedica, OncoSec, Arvinas, Taiho Oncology, OBI Pharma, Sun Pharma, and Relay Therapeutics.