Llombart-Cussac A, Pérez-García JM, Bellet M, et al. - Researchers investigated if fulvestrant is superior to letrozole when combined with palbociclib in the first-line scenario for patients with endocrine-sensitive, hormone receptor–positive, ERBB2-negative advanced breast cancer.

• Randomized, open-label, phase 2 trial recruiting 486 patients to receive palbociclib plus fulvestrant or letrozole.

• For fulvestrant-palbociclib and letrozole-palbociclib, median investigator-assessed progression-free survival of 27.9 months vs 32.8 months, was recorded, respectively; this difference did not appear statistically significant.

• Overall there appeared no improvement in progression-free survival in correlation with providing fulvestrant-palbociclib vs letrozole-palbociclib, confirming letrozole as the preferred palbociclib partner in this patient population.