Early breast cancer: EU approves Enhertu after surgery when tumour tissue remains

The European Commission has approved the cancer drug Enhertu (trastuzumab deruxtecan) for a new group of patients. It may now be used in adults with early-stage HER2-positive breast cancer who still have invasive tumour tissue after chemotherapy and antibody treatment given before surgery. Manufacturers AstraZeneca and Daiichi Sankyo announced the decision on 27 October. It is the drug's first EU approval in the early stage of the disease, where treatment aims at a cure. The European Medicines Agency's committee CHMP had previously recommended approval.

The decision is based on the Phase III trial DESTINY-Breast05, which enrolled 1,635 patients across several continents and compared Enhertu with the previous standard drug T-DM1 (trastuzumab emtansine). According to the companies, Enhertu cut the risk of invasive recurrence or death by 53 per cent. After three years, 92.4 per cent of patients treated with Enhertu were free of invasive disease, compared with 83.7 per cent on T-DM1. The results were published in the New England Journal of Medicine. The companies said no new safety concerns were identified.

Lead investigator Sibylle Loibl of the German Breast Group and Goethe University Medicine Frankfurt said, according to the announcement, that reducing the risk of recurrence is critical for long-term outcomes. According to the manufacturers, about one in five breast cancers is HER2-positive, meaning the tumour cells carry increased amounts of a particular protein on their surface. Enhertu is already approved for this use in more than 35 countries. Whether the therapy is suitable in an individual case is decided by the treating doctors.