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Found 1 Presentation For Request "291p"

Poster Display session

291P - Trastuzumab emtansine in HER2-positive metastatic breast cancer after pertuzumab and trastuzumab: TDM1RM Study

Presentation Number
291P
Speakers
  • Jeronimo Martinez-Garcia (El Palmar, Spain)
Date
17.09.2020

Abstract

Background

Trastuzumab emtansine (TDM1) is indicated for the treatment of metastatic HER2-positive breast cancer (HMBC) after progression on prior trastuzumab and taxane (TT). There are few data on its efficacy after pertuzumab, trastuzumab and taxane (PTT). The present study is a regional multicenter retrospective evaluation of the activity of TDM-1 after front line pertuzumab based therapy.

Methods

All three oncology centers of “Region de Murcia” participated in a restrospective observational study. Patients diagnosed with HMBC treated with a minimum of 2 cycles of TDM1 after PTT were included. Efficacy and safety were analysed and compared with TH3RESA and EMILIA study.

Results

Between Feb 2015 until Apr 2020, 52 patients with HMBC were treated with TDM1 after PTT. After a median of follow-up of 33 months, 8 patients were still under TDM1 therapy and 30 patients (58%) have died at the end of the study. Median progression free survival (PFS) was 8,4 months (95% IC 6,9 – 9,9) and median overal survival (OS) was 23,6 months (95% IC 17,5 – 29,7). Overall Rate Response (ORR) was 42%. The most frequent grade 3 toxicity was thrombocytopenia (8%) (see table). No dose-limiting cardiotoxicity was seen.

Th3resa Study EMILIA Study TDM1RM Study
N 404 495 52
Age (median, range) 53 (27-89) 53 (25-84) 50 (29-75)
ECOG – % 0 1 2 45 50 5 60 39 15 61 23
Hormone-receptor – % HR+ HR- 51 46 57 41 64 35
Visceral disease – % 75 67 79
Previously brain metastasis – % 10 9 38
Prior chemotherapy regimens – % 0 or 1 >1 (≤ 3 regimens) 33 (> 3) 67 61 39 81 19
ORR – no. (%) 108 (31) 173 (44) 22 (42)
Median duration of response – median (95% IC) 9,7 (6,6-10,5) 12,6 (8,4 – 20,8) 9,7 (6,6 – 12,8)
PFS (median, 95% IC) 6,2 (5,6 – 6,9) 9,6 8,4 (6,9 – 9,9)
OS (median, 95% IC) 22,7 (19,4 – 27,5) 30,9 23,6 (17,5 – 29,7)
Dose reduction - % 9 16 25
Grade 3 toxicity – no. (%) Astenia Anemia Thrombopenia Neutropenia 4 (1) 14 (4) 24 (6) 10 (3) 12 (2) 13 (3) 63 (13) 10 (2) 2 (4) 1 (2) 4 (8) 2 (4)

Conclusions

T-DM1 was an effective and well-tolerated treatment in routine clinical practice in patients with HMBC after PTT. ORR, PFS and OS were similar than pivotal study after only trastuzumab-taxane. We observed a similar toxicity of TDM1. We had a higher incidence of brain metastases.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.

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