XXII Congresso Brasileiro de Oncologia Clínica

Dados do Trabalho


Título

REAL-WORLD TREATMENT OUTCOMES IN METASTATIC HR+ HER2- BREAST CANCER PATIENTS EXPOSED TO CDK4/6 INHIBITORS

Introdução

Cyclin-dependent kinase 4/6 inhibitors (iCDK4/6) have recently been developed and introduced into clinical practice. However, due to the strict criteria used in pivotal trials, the reproducibility of these results in the real-life setting needs to be confirmed, in order to validate the efficacy and safety of this new therapeutic option.

Objetivo

Describe real-world data of iCDK4/6 in the Brazilian population.

Método

We retrospectively analyzed data from patients (PTS) with confirmed HR+/HER2- metastatic breast cancer treated with iCDK4/6: Ribociclib(R), Palbociclib(P), or Abemaciclib(A). A checklist of 191 fields was completed for each patient using the REDCap platform. Outcomes evaluated included, among others, median time to treatment discontinuation (mTTD), median progression-free survival (mPFS), and overall response rate (ORR) by evaluator assessment.

Resultado

Between 01/2015 and 06/2021, 142 PTS were treated with an iCDK4/6 (79 P, 42 R, 21 A). The median age was 59 years, 68.7% had recurrent disease, and concomitant ovarian suppression was used in 34% of PTS. Regarding metastatic sites: 36.7%, 35.4%, 27.9% had 1, 2 or 3+ sites, respectively. 56.5% PTS received iCDK4/6 in first treatment line. Letrozole (45.6%) or Fulvestrant (43.5%) were the most frequently used hormonal agents. The mPFS was 29m (R) vs 22m (P) vs 6m (A), in favor of R (p=0.002), but a higher proportion of PTS received R in the first line setting compared to the other two drugs. However, no difference was seen when the analysis was restricted to the first line scenario (p=0.17). Higher mPFS was statistically correlated with early lines of treatment (p<0.001), lower number of metastatic sites (p=0.002), absence of hepatic metastasis (p<0.001), and normal CEA (p=0.001) and CA 15-3 levels (p=0.001) at the beginning of treatment. Sixty-four PTS required one (34 P, 18 R, 12 A) and 19 needed two dose reductions (13 P, 3 R, 2 A). mTTD was similar among the agents (p=0.072). ORR was 76.2%(R) vs 62% (P) vs 42.9% (A). More patients had complete response with R and P (p=0.009), with no difference for partial response and stable disease (p=0.622). Dose delays occurred in 70% and adverse effects in 94.5% of the population (70% grade 3-4).

Conclusão

Our results confirm the efficacy and tolerability of iCDK 4/6 in routine clinical practice. To our knowledge, this is the first real-world data describing the use of this therapeutic strategy and the first study to compare the efficacy and toxicity of R, P and A in the Brazilian population.

Palavras-chave

Cyclin-dependent kinase 4/6 inhibitors; Real-world data; Brazilian population

Área

Oncologia - Tumores de Mama

Autores

MARCELLO MORO QUEIROZ, KARINA PEREZ SACARDO, MAURICIO FERNANDO SILVA ALMEIDA RIBEIRO, LUIZA LARA GADOTTI, RODRIGO SADDI, LEANDRO JONATA CARVALHO OLIVEIRA, RUDINEI DIOGO MARQUES LINCK, MARCELO ROCHA SOUZA CRUZ, ROMUALDO BARROSO-SOUSA, MARINA SAHADE GONÇALVES, TATIANA STRAVA CORREA, MAX SENNA MANO, DANIELE ASSAD SUZUKI, ANDREA KAZUMI SHIMADA, ARTUR KATZ