The phase III evaluation compared the AZ treatment’s performance against the standard of care for HER2-positive metastatic breast cancer, the European Society of Medical Oncology (ESMO) annual conference was told.
It involved 500 patients in Asia, Europe, North America, Oceania and South America.
Around 75% of women showed no progression in their disease after 12 months compared to 34% of those treated with trastuzumab emtansine (T-DM1), while progression-free survival was improved from 7.2 months to 25.1 months.
Just over 94% of all Enhertu patients were alive after 12 months, compared to 85.9% of T-DM1 patients.
“We and consensus already anticipated Enhertu to leapfrog Kadclya in second-line mBC (metastatic breast cancer). Despite this, we take away some important incremental positives for Enhertu following the ESMO data,” Wall Street bank Citigroup said.
In early afternoon trade, the stock was changing hands for GBP90.10, up 1.9% on the day.