Roche announced the submission of a Marketing Authorisation to the European Medicines Agency (EMEA) for Herceptin (trastuzumab) as treatment for advanced HER2-positive and hormone receptor-positive breast cancer.
The application is based on data from the international TAnDEM study which showed that the addition of Herceptin to hormonal therapy doubles the median progression-free survival (amount of time a patient's cancer is kept under control), from 2. 4 months to 4.8 months.1
HER2-positive breast cancer, which affects 20 to 30 per cent of women with breast cancer, is an aggressive form of the disease that requires special and immediate attention because the tumours are fast-growing and there is a higher likelihood of relapse.2 Up to a half of HER2-positive breast cancers are also hormone receptor-positive, a form of the disease that has typically been considered 'lower-risk,' due to successful treatment with hormonal therapies.3 However, TAnDEM is the first randomised study to show that this specific subset of 'co-positive' patients (both HER2- and hormone receptor positive) is actually 'higher-risk', making the positive results with Herceptin even more meaningful.
"The results from the TAnDEM study show once again that Herceptin should be the backbone for all HER2-positive breast cancer patients - it consistently benefits patients regardless of whether it is given in the early- or advanced-stage settings, or whether it is in combination with chemotherapy, hormonal therapy, or as a single agent," said Eduard Holdener, Global Head of Roche Pharma Development. "This combination offers a new treatment regimen for patients who suffer from a particularly aggressive form of breast cancer, and we are pleased to have been able to progress this application so quickly."
TAnDEM, conducted by Roche, is a randomised, phase III trial, which evaluated Herceptin in combination with the hormonal therapy anastrozole versus anastrozole alone as first-line therapy (or second-line hormonal therapy) in postmenopausal women with advanced (metastatic), HER2-positive and hormone receptor-positive (ER-positive and/or PR-positive) breast cancer. Enrolment to the trial began in 2001, and 208 HER2 and hormone receptor co-positive patients were randomized at 77 centres in 22 countries across the world.
Median progression-free survival, the primary endpoint of the trial, was 4.8 months for patients who received the combination compared to 2.4 months for patients who received hormonal therapy alone (p = 0.0016). Patients in the combination arm also responded significantly better to treatment (overall response rate was 20.3% versus 6.8%; p = 0.018). There was also a positive trend in median overall survival (28.5 months versus 23.9 months; p = 0.325); this is despite the fact that in the hormonal therapy alone arm, more than half of patients (58/104) crossed over to receive Herceptin during the trial when their disease had progressed, and an additional 15 (out of 104) patients received Herceptin at a later time point.
Overall safety data in both arms of the trial were acceptable given the known safety profile of each of the drugs in the advanced breast cancer setting. Patients in this study will continue to be followed for any side-effects.