Trade News
Basel, 28 May 2009
New form of targeted therapy offers further hope to patients with advanced HER2-positive breast cancer
Tumour shrinkage experienced with novel targeted therapy
Final results from a phase II study presented at ASCO show that 25% of women with advanced HER2-positive breast cancer experienced remarkable shrinkage of their tumours, when treated with a new agent called trastuzumab-DM1 (T-DM1). T-DM1 is a new and highly specialised cancer treatment that combines two approaches to treating cancer in one medicine. It represents the first treatment for breast cancer in a new class of powerful drugs known as antibody-drug conjugates (ADC).
The two components of T-DM1 are: the well-known and proven treatment trastuzumab (Herceptin), an antibody that specifically targets HER2, and DM1, a chemotherapy agent. Trastuzumab delivers DM1 to the tumour where it kills cells overproducing HER2, which cause cancer. By combining both of these components, T-DM1 is able to specifically target cancer cells and maximise clinical benefit while minimising harmful side effects.
“These results are welcome news for the thousands of women with advanced HER2-positive breast cancer who have few, if any remaining options,” said Dr Jose Baselga (Vall d’Hebron University Hospital, Barcelona, Spain). “To see such efficacy with a monotherapy is highly unusual and it is important that we continue to explore this promising agent further in phase III studies. I am very pleased to be an investigator for T-DM1.”
In the phase II study approximately 35% of patients either saw their tumours shrink, or their disease stabilised for at least six months. When the HER2-status of patients was re-assessed in a central lab, the percentage of patients who experienced such a clinical benefit was even as high as 44%.
The single-arm, open-label phase II study enrolled 112 patients and was conducted in the US. EMILIA, a global phase III study investigating T-DM1 in patients whose breast cancer has progressed following previous anti-HER2 therapy is ongoing.
T-DM1 potentially represents another option for patients with metastatic disease, for which there is no cure.
About breast cancer
Breast cancer is the most common cancer among women worldwide.1 Each year more than one million new cases of breast cancer are diagnosed worldwide, and nearly 400,000 people will die of the disease annually. In HER2-positive breast cancer, increased quantities of the HER2 protein are present on the surface of the tumour cells. This is known as ‘HER2 positivity’. High levels of HER2 are present in a particularly aggressive form of the disease which responds poorly to chemotherapy. Research shows that HER2-positivity affects approximately 20–30% of women with breast cancer.
About the Phase II study
The T-DM1 phase II study was a multi-institutional, open-label, single arm trial. The study took place in the United States of America and enrolled 112 women whose breast cancer had progressed following previous treatment with two or more HER2-targeted therapies. The primary endpoint was objective response rate (ORR) as determined by an independent review and the secondary endpoints include:
- duration of response (DoR)
- progression-free survival (PFS)
- clinical benefit rate (CBR)
T-DM1 is the first and only single-agent molecule being studied in a class of investigational agents known as antibody-drug conjugates (ADC) in HER2-positive breast cancer. T-DM1 is made up of trastuzumab (Herceptin), a well-known and proven treatment for HER2-positive cancer, and DM1, a highly potent anti-microtubule derivative. The rationale behind this coupling is to increase the anti-tumour efficacy by bringing trastuzumab and DM1 directly to the cancer cell with limited or no increase in treatment-related side effects. Results from the first phase were presented at ASCO last year.
About EMILIA (phase III study)
Currently a global phase III study (EMILIA) evaluating T-DM1 for second-line advanced HER2-positive breast cancer is ongoing. The 580-patient randomised study was initiated in February 2009 and is comparing single agent T-DM1 to lapatinib plus capecitabine.
About Roche
Headquartered in Basel, Switzerland, Roche is a leader in research-focused healthcare with combined strengths in pharmaceuticals and diagnostics. Roche is the world’s largest biotech company with truly differentiated medicines in oncology, virology, inflammation, metabolism and CNS. Roche is also the world leader in in-vitro diagnostics, tissue-based cancer diagnostics and a pioneer in diabetes management. Roche’s personalised healthcare strategy aims at providing medicines and diagnostic tools that enable tangible improvements in the health, quality of life and survival of patients.
In 2008, Roche had over 80,000 employees worldwide and invested almost 9 billion Swiss francs in R&D. The Group posted sales of 45.6 billion Swiss francs. Genentech, United States, is a wholly owned member of the Roche Group. Roche has a majority stake in Chugai Pharmaceutical, Japan. For more information: www.roche.com.
References
1) World Health Organization, http://www.who.int/cancer/detection/breastcancer/en/