While results of the PALOMA-2 study did not show a survival benefit for the overall population on the combination of palbociclib and letrozole but did show an overall survival benefit in Black patients on the combination therapy.
Adam Brufsky, MD, PhD, FACP, professor of medicine at the University of Pittsburgh School of Medicine, associate division chief for the Division of Hematology/Oncology at the University of Pittsburgh School of Medicine's Department of Medicine, medical director of the Magee-Women's Cancer Program, associate director for clinical investigations at UPMC Hillman Cancer Center, and codirector of the Comprehensive Breast Cancer Center, discusses the results of palbociclib (Ibrance) as treatment for African American patients with estrogen receptor-positive, HER2-negative, advanced breast cancer.
Results from the phase 3 PALOMA-2 study (NCT01740427) showed that there was not an overall survival (OS) benefit in the overall population treated with Palbociclib plus letrozole (Femara) but in patients that identified as Black or Hispanic. Brufsky discusses the results for Black patients with advanced breast cancer on this drug and how this could impact a clinician’s decision for treatment.
0:08 | I think the most important part of this is that progression free survival with aromatase inhibitors was about 10 months, [but] it was about 18 months with palbociclib aromatase inhibitor. So, it added about 8 months in absolute PFS, [and] in the real world the hazard ratio was about .74, which is a little bit worse than what we saw in PALOMA-2. But in terms of OS, at least in this analysis from palbociclib aromatase inhibitor, was not reached with an aromatase inhibitor alone is about 28 months, which is much shorter than we expect. And again, I think that the hazard ratio for survival when adjusted was .56.
0:44 | Again, these are probably confounded by a lot of unknown bias, so we don't know, but I think in the PFS there is a benefit. But in the African American population, and in OS, there does appear to be a benefit that is statistically significant in this population. Again, this is not a randomized trial, but I think it at least informs us that in an African American population, these drugs that are working in the absolute numbers for OS and PFS, which is a little bit less than we see in the large, randomized trial and in the large real-world analysis. So, I think that this this is just another piece of data that clinicians can use when they decide to treat people with aromatase inhibitors or CDK46 inhibitors like palbociclib.