Dr. Cristofanilli on Optimal Targeted Therapies in Metastatic HR-Positive Breast Cancer

Massimo Cristofanilli, MD, director, Breast Medical Oncology, associate director, Precision Oncology, co-leader, Breast Cancer Disease Management Team, scientific director, Englander Institute of Precision Medicine, Meyer Cancer Center, Weill Cornell Medicine and NewYork-Presbyterian Hospital, discusses the variety of targeted therapies available in metastatic hormone receptor–positive breast cancer.

Targeted therapy has shown promise in this population of patients who have progressed after first-line therapy, with agents such as alpelisib (Piqray), which is FDA approved in the second line in patients with PIK3CA-mutated tumors who have progressed on CDK4/6 inhibitors, Cristofanilli says. Research is also being conducted to define more effective agents that will target ESR1 mutations in patients who have received fulvestrant (Faslodex), which may be resistant to some variants of ESR1, Cristofanilli explains.

Identifying mutations, first in retrospective trials and then in prospective trials, helps to better define the subsets of patients who may benefit from certain targeted therapies, Cristofanilli notes. Many studies are testing novel selective estrogen receptor degraders and selective estrogen receptor modulators, which may emerge as new monotherapies or in combination with other agents, Cristofanilli says.

HER2 mutations, different from HER2 amplifications, which can already be treated effectively with HER2-targeted therapies, are also of note in the estrogen receptor–positive disease arena, Cristofanilli explains. Overall, patients with breast cancer have multiple treatment options that can be sequenced for optimal results, Cristofanilli concludes.