Survival Analysis of Ribociclib + Endocrine Therapy in HR+/HER2- ABC Patients With Visceral Metastases

The ML-2, -3, and -7 trials have shown that the combination of RIB and ET provides significant benefits in progression-free survival (PFS) and overall survival (OS) for patients with hormone receptor-positive and HER2-negative advanced breast cancer. Visceral metastases indicate an unfavorable prognosis, with a notably low survival rate observed in patients with hepatic metastases. Researchers presented a combined survival analysis of the ML-2, -3, and -7 clinical trials in patients with metastases in visceral organs, including those affecting the liver. In the ML-2 study, female patients who had undergone menopause were randomly assigned in a 1:1 ratio to receive either first-line treatment with RIB or placebo (PBO) combined with letrozole. In the ML-3 study, female patients who had undergone menopause were randomly assigned in a 2:1 ratio to receive either RIB or PBO along with fulvestrant in either the first-line (1L) or second-line (2L) treatment setting. In the ML-7 study, female patients who had not yet reached menopause were randomly assigned in a 1:1 ratio to receive either 1 liter of ribociclib or a placebo, along with goserelin and either a nonsteroidal aromatase inhibitor or tamoxifen. Only patients in the nonsteroidal aromatase inhibitor arm were included in the analysis.

A noteworthy improvement in progression-free survival (PFS) and overall survival (OS) was noted with RIB in patients with metastases in visceral organs, including those with liver metastases or those with metastases in three or more sites, across the combined population of first-line and second-line treatments. The observed advantage remained notable in the first-line (1L) subset, encompassing patients with a poorer prognosis, such as those with liver metastases or three or more metastatic sites, who attained a median overall survival (OS) of approximately four to five years with ribociclib (RIB). There were no indications of any fresh safety signals, such as liver enzyme elevations, even in patients with pre-existing liver metastases. This extensive pooled analysis of the metastatic lesion trials affirms the uniform survival advantage of ribociclib in combination with endocrine therapy for patients with visceral metastases, who have traditionally exhibited an unfavorable prognosis. This analysis highlights the significant advantage of RIB in individuals with unfavorable outcomes within the visceral metastases subgroup, specifically patients with hepatic metastases and those with multiple metastatic sites, particularly in the first-line population.

Source: https://oncologypro.esmo.org/meeting-resources/esmo-congress/pooled-exploratory-analysis-of-survival-in-patients-pts-with-hr-her2-advanced-breast-cancer-abc-and-visceral-metastases-mets-treated-with-r

Clinical Trail: https://clinicaltrials.gov/ct2/show/NCT02422615

D.A. Yardley, Y.S. Yap, H.A. Azim, R.H. De Boer, M. Campone, A. Ring, M. De Laurentiis, J. O’Shaughnessy, J. Cortés, Y. Chattar, A. Thuerigen, J.P. Zarate, A. Nusch/Pooled exploratory analysis of survival in patients (pts) with HR+/HER2- advanced breast cancer (ABC) and visceral metastases (mets) treated with ribociclib (RIB) + endocrine therapy (ET) in the MONALEESA (ML) trials/Annals of Oncology (2022) 33 (suppl_7): S85-S87. 10.1016/annonc/annonc1039