T-DM1 for Advanced HER2-positive Breast Cancer: The Royal Marsden Experience

In Clinical Studies News by Barbara Jacoby

By: Dawn O’Shea

From: medscape.com

Real-world data from the Royal Marsden Hospital show that the side effect profile of ado-trastuzumab emtansine (T-DM1) in the treatment of advanced human epidermal growth factor receptor 2 (HER2)-positive breast cancer is similar to that shown in clinical trials. However, there are a number of differences.

A study published in  Cancer Treatment and Research Communications  identified 128 patients with advanced HER2-positive breast cancer (median age, 55 years) on T-DM1 from 1 January 2014 to 12 March 2018.

Among participants, 89.8% had Eastern Cooperative Oncology Group performance status 0-1 and 21.1% had presented with de novo metastatic disease. More than half (57.8%) had estrogen receptor-positive disease, and 38.3% had central nervous system involvement.

A total of 88.3% of patients had received trastuzumab for advanced disease (with pertuzumab in 28.9%), and 11.7% had only received trastuzumab in the adjuvant setting.

Grade ≥3 adverse events occurred in 35.9% of patients – liver toxicity (19.5%), anaemia (6.2%) and thrombocytopenia (4.7%). Peripheral neuropathy of any grade was reported in 21.9% of cases, bleeding in 9.4% and ejection fraction decline in five patients.

Median progression-free survival was 8.7 months, and overall survival was 20.4 months. Prior pertuzumab did not influence survival outcomes.

The safety of T-DM1 in the Royal Marsden population is similar to that reported in clinical trials; however, this study found higher rates of peripheral neuropathy and deranged liver function.

Battisti NMLL, Rogerson F, Lee K, Shepherd S, Mohammed K, Turner N, McGrath S, Okines A, Parton M, Johnston S, Allen M, Ring A. Safety and efficacy of T-DM1 in patients with advanced HER2-positive breast cancer The Royal Marsden experience. Cancer Treat Res Commun. 2020 Jun 27 [Epub ahead of print]. doi: 10.1016/j.ctarc.2020.100188. PMID: 32619830 Full text.