Trial Demonstrates High Efficacy of Antibody-Drug Conjugate in Preventing Early-Stage Breast Cancer Recurrence

The trial enrolled 512 patients across cancer centers with 384 participants receiving T-DM1 and 128 receiving chemotherapy and trastuzumab. Five years post-treatment, the T-DM1 group showed a 97% rate of no cancer recurrence. Additionally, the study highlighted that the rate of clinically relevant toxicities was similar in both groups. However, patient-reported outcomes revealed that those treated with T-DM1 experienced a better quality of life, reporting less neuropathy, less hair loss, and improved work productivity compared to those who received chemotherapy and trastuzumab.

Overall, the study underscored the potential of T-DM1 as an effective and well-tolerated treatment option for patients with early-stage HER2-positive breast cancer, particularly those at higher risk of recurrence.

“The ATEMPT trial has taught us that one year of T-DM1 after surgery for patients with a stage 1 HER2-positive cancer leads to outstanding long-term outcomes, making it a reasonable treatment approach for select patients,” says senior author Sara Tolaney.

Reference: Paolo Tarantino et al., Adjuvant Trastuzumab Emtansine Versus Paclitaxel Plus Trastuzumab for Stage I Human Epidermal Growth Factor Receptor 2–Positive Breast Cancer: 5-Year Results and Correlative Analyses From ATEMPT. JCO 0, JCO.23.02170; DOI:10.1200/JCO.23.02170