A. Menichetti (Padova, Italy)

IOV - Istituto Oncologico Veneto IRCCS

Author Of 1 Presentation

 On-Demand ePoster Display

122P - Abemaciclib in HR+/HER2- metastatic breast cancer: a real-world experience

Abstract

Background

Abemaciclib is approved for HR+/HER2- metastatic breast cancer in combination with endocrine therapy (ET). We evaluated safety and efficacy of abemaciclib in association with ET in a single-institution cohort.

Methods

Patients with HR+/HER2- metastatic breast cancer treated with abemaciclib in combination with ET as first or second line between April 2019 and November 2020 at Istituto Oncologico Veneto of Padova were identified. Clinicopathological characteristics, adverse events and their grade (according to CTCAE 5.0 criteria) were collected. Objective response rate (ORR) according to RECIST 1.1 was also evaluated.

Results

72 patients were included: 52 received abemaciclib as first line, 20 as second line; in 49 patients abemaciclib was administer in combination with an aromatase inhibitor, in 23 with fulvestrant. 95.8% of patients experienced at least one adverse event. The most common was diarrhea (79.2%), mainly G1 (66.7% of cases). Other common toxicities were: neutropenia (56.9%), increased serum creatinine (38.9%), anemia (37.5%), nausea (34.7%), fatigue (23.6%) and hypertransaminasemia (22.2%). Toxicities were mainly low grade; 10.1% of adverse events where G3-4. 48.6% of patients required a temporary interruption of abemaciclib and 45.8% a dose reduction. All 17 patients aged ≥70 required a dose reduction. A concomitant palliative radiotherapy was administered in 16 patients: in all cases radiotherapy was regularly completed; a temporary interruption of abemaciclib was required in 3 patients due to hematologic toxicities. In patients with measurable disease, ORR was 55.7%, significantly higher in first line compared to second line (70.5% vs 17.7%, p<0.001). ORR was not significantly different between full and reduced dose (46.9% vs 65.5%, p=0.143). At the time of the present analysis, 51 patients are still on therapy. Treatment discontinuations were due to disease progression in 17 patients, and to adverse events in 4 (G3 increased ALT in 1 patient and persistent G2-3 cutaneous toxicity in 3 patients).

Conclusions

In a real-world population, abemaciclib was associated with a meaningful rate of objective response, with a favourable safety profile. Side effects were mostly low grade, manageable with temporary interruptions or dose reductions.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

M.V. Dieci: Honoraria (self): Eli Lilly; Honoraria (self): Genomic Health; Honoraria (self): Novartis; Honoraria (self): Celgene. G. Griguolo: Travel/Accommodation/Expenses: Pfizer; Travel/Accommodation/Expenses: Novartis; Travel/Accommodation/Expenses: Daiichi Sankyo. V. Guarneri: Honoraria (self): Roche; Honoraria (self): Novartis; Honoraria (self): Eli Lilly; Honoraria (self): MSD. All other authors have declared no conflicts of interest.

Collapse