- Medical Updates

The EMA's Committee for Medicinal Products for Human Use ( CHMP ) has recommended the approval of Kadcyla ( Trastuzumab emtansine ) for the adjuvant treatment of adult patients with HER2-positive early breast cancer ( eBC ) who have residual invasive disease, in the breast and/or lymph nodes, after neoadjuvant Taxane-based and HER2-targeted therapy.

The recommendation from the CHMP is based on results from the phase III KATHERINE study which showed that Trastuzumab emtansine has significantly reduced the risk of invasive breast cancer recurrence or death from any cause ( invasive disease-free survival; iDFS ) by 50% ( hazard ratio, HR=0.50, 95% CI 0.39-0.64, p less than 0.001 ) compared to Trastuzumab ( Herceptin ) as an adjuvant treatment in people with HER2-positive eBC who have residual invasive disease after neoadjuvant taxane and Trastuzumab-based treatment.
At three years, 88.3% of people treated with Trastuzumab emtansine did not have their breast cancer return compared to 77.0% treated with Trastuzumab, an absolute improvement of 11.3%.
The safety profile of Trastuzumab emtansine was consistent with that observed in previous studies.

The importance of the KATHERINE data was recognised in May 2019 by the US Food and Drug Administration ( FDA ) which accelerated the approval of Kadcyla for the adjuvant treatment of people with HER2-positive eBC with residual invasive disease after neoadjuvant treatment under Real-Time Oncology Review ( RTOR ) and Assessment Aid pilot programmes. This led to an approval just over 12 weeks after completing the submission.

KATHERINE is an international, multi-centre, two-arm, randomised, open-label, phase III study evaluating the efficacy and safety of Trastuzumab emtansine versus Trastuzumab as an adjuvant therapy in people with HER2-positive eBC who have pathological invasive residual disease in the breast and/or axillary lymph nodes following neoadjuvant therapy that included Trastuzumab and taxane-based chemotherapy.
The primary endpoint of the study is iDFS, which this study defined as the time from randomisation to the time that the patient is free from invasive breast cancer recurrence or death from any cause. Secondary endpoints include iDFS including second primary non-breast cancer, disease-free survival and overall survival.

Trastuzumab emtansine is an antibody-drug conjugate ( ADC ) engineered to deliver potent chemotherapy directly to HER2-positive cancer cells, potentially limiting damage to healthy tissues. It combines two anti-cancer properties joined together by a stable linker: the HER2-targeting properties of Trastuzumab ( the active ingredient in Herceptin ) and the chemotherapy agent DM1. ( Xagena )

Source: Roche, 2019