Efficacy and safety of T-DM1 in the 'common-practice' of HER2+ advanced breast cancer setting: a multicenter study.

Alessandra Fabi,Michelino De Laurentiis,Michele Caruso,Marianna Giampaglia,Agnese Fabbri,Luca Moscetti,Daniele Generali,Michelangelo Russillo,Rosalba Rossello,Daniela Cianniello,Daniele Santini,Giuseppa Scandurra,Gianfranco Filippelli,Alberto Zambelli,Grazia Arpino,Mariangela Ciccarese,Luisa Carbognin,Diana Giannarelli,Filippo Montemurro,Katia Cannita,Nicla La Verde,Ida Paris,Francesco Cognetti,Anna Maria D'Ottavio,Simonetta Chiara Stani ,Daniele Adami ,Elisabetta Della Valle ,V Leonardi

doi:10.18632/oncotarget.16373

Abstract

Ado-trastuzumab emtansine (T-DM1) is an antibody-drug conjugate approved for the treatment of patients with human epidermal growth factor receptor 2 (HER2)-positive, metastatic breast cancer (mBC). The aim of this ‘field-practice’ study was to investigate the efficacy and safety of T-DM1, focusing on treatment line, previous lapatinib treatment and patterns of metastasis. Three hundred and three patients with HER2-positive mBC who received T-DM1 were identified by reviewing the medical records of 24 Italian Institutions. One hundred fourty-nine (49%) and 264 (87%) had received prior hormonal treatment and/or anti-HER2 targeted therapy, respectively. Particularly, 149 patients had been previously treated with lapatinib. The objective response rate (ORR) was 36.2%, and 44.5% when T-DM1 was administrated as second-line therapy. Considering only patients with liver metastases, the ORR was 44.4%. The median progression-free survival (PFS) was 7.0 months in the overall population, but it reached 9.0 and 12.0 months when TDM-1 was administered as second- and third-line treatment, respectively.In conclusion, in this ‘real-word’ study evaluating the effects of T-DM1 in patients with HER2-positive mBC who progressed on prior anti-HER2 therapies, we observed a clinically-relevant benefit in those who had received T-DM1 in early metastatic treatment-line and in subjects previously treated with lapatinib.

Highlights

Trastuzumab, a humanized IgG1 monoclonal antibody, was the first targeted therapy against the human epidermal growth factor receptor 2 (HER2) showing clinical efficacy in patients with breast cancer [1]
We focused our analysis on the effects of T-DM1 according to the line of treatment, a previous lapatinib administration and the presence of visceral metastases
We analyzed an unselected, heavily pretreated population of metastatic breast cancer (mBC) patients, our data are fairly consistent with those reported in T-DM1 clinical trials

Summary

Introduction

Trastuzumab, a humanized IgG1 monoclonal antibody, was the first targeted therapy against the human epidermal growth factor receptor 2 (HER2) showing clinical efficacy in patients with breast cancer [1]. In this ‘real-word’ study evaluating the effects of T-DM1 in patients with HER2-positive mBC who progressed on prior anti-HER2 therapies, we observed a clinicallyrelevant benefit in those who had received T-DM1 in early metastatic treatment-line and in subjects previously treated with lapatinib.

Results

Conclusion