Monday, June 7, 2010

New drug improves overall survival of women with metastatic TNBC


From a News Release from Eisai Oncology

CHICAGO--(BUSINESS WIRE)--Results of a Phase III study presented today at the American Society of Clinical Oncology (ASCO) Annual Meeting showed that Eisai’s eribulin mesylate significantly improved median overall survival (OS) compared with Treatment of Physician’s Choice (TPC) in heavily pre-treated metastatic breast cancer patients.


These results were presented as part of an ASCO-sponsored press briefing; additional details from the study will be presented in an oral session on June 8, 2010 at 9:30 a.m. in East Hall D1 at Chicago's McCormick Place. The study abstract has also been selected for presentation at the 2010 Best of ASCO® Meetings, which will be held in San Francisco and Boston in the United States and in several countries around the world in the months following the ASCO Annual Meeting.


The Phase III “EMBRACE” study (Eisai Metastatic Breast Cancer Study Assessing Physician’s Choice Versus Eribulin E7389) met its primary endpoint of overall survival, showing that patients who received eribulin survived a median of 2.5 months longer than patients who received TPC (overall survival of 13.12 months versus 10.65 months, respectively, p=0.04). Results from EMBRACE also showed that a secondary endpoint of overall response rate (ORR) was statistically significant. Another secondary endpoint, progression free survival (PFS), was supportive of the primary endpoint but did not reach statistical significance.


“To date, no single-agent Phase III clinical trial has demonstrated improved survival in women with heavily pre-treated metastatic breast cancer,” said Chris Twelves, M.D., lead investigator for the EMBRACE study and Professor of Clinical Cancer Pharmacology and Oncology from the University of Leeds and St. James’s University Hospital, Leeds, United Kingdom. “These results showed that eribulin significantly improved overall survival versus a variety of agents used in a real-world setting, which previously no single agent has shown.”


The most frequently reported adverse events (AEs) among patients treated with eribulin were asthenia, or fatigue (53.7%), neutropenia, or low white blood cell counts (51.7%), alopecia, or hair loss (44.5%) and peripheral neuropathy, or numbness and tingling in different parts of the body (34.6%). Treatment-emergent serious AEs were reported for 25 percent of patients in the eribulin group and 25.9 percent of patients in the TPC arm.


About the Study

EMBRACE was an open-label, randomized, multi-center study of 762 patients with locally recurrent or metastatic breast cancer who were previously treated with at least two and a maximum of five prior chemotherapies (≥2 for advanced disease), including an anthracycline and a taxane. Patients must have been refractory to the most recent chemotherapy, documented by progression on or within six months of therapy. The study was designed to compare overall survival in patients treated with eribulin versus a TPC arm, reflecting a real-world clinical setting where a variety of agents are used to treat patients with advanced breast cancer.


Patients were randomized in a two-to-one ratio to receive either eribulin (1.4 mg/m2 administered intravenously for two-to-five minutes on days 1 and 8 of a 21-day treatment cycle) or TPC. TPC was defined as any single agent chemotherapy, hormonal treatment or biological therapy approved for the treatment of cancer; or palliative radiotherapy administered according to local practice. The median age of study participants was 55 (range 27-85); 16 percent of patients had HER2 positive breast cancer and 19 percent had breast cancer that was negative for estrogen, progesterone and HER2 receptors (triple-negative breast cancer).


About Metastatic Breast Cancer

Worldwide, more than one million women a year are diagnosed with breast cancer. Approximately 50 percent of women worldwide initially diagnosed with breast cancer are expected to develop recurrent or metastatic disease within 15 years of their first diagnosis. Only one in five women with metastatic breast cancer survives longer than five years. In the United States, an estimated 155,000 women are currently living with metastatic breast cancer, and that number is projected to increase to 162,000 by 2011.


“Women with advanced breast cancer are in critical need of new treatment options,” said Alton Kremer, M.D., Ph.D, Global Head of Clinical Development for Oncology at Eisai Inc. “In this study, eribulin has shown an improvement in survival, and if approved by health authorities, it may offer patients a new treatment option at this stage of the disease.”


About Eribulin

Eribulin mesylate (E7389) is an investigational agent being evaluated as a potential treatment for locally advanced or metastatic breast cancer. A non-taxane, microtubule dynamics inhibitor, eribulin is a synthetic analog of halichondrin B, which is derived from a natural product isolated from the marine sponge Halichondria okadai.


On March 30, 2010, Eisai announced it had submitted simultaneous regulatory applications for approval of eribulin mesylate for the treatment of locally advanced or metastatic breast cancer to agencies in Japan, the United States and the European Union (EU). The eribulin New Drug Application (NDA) was granted priority review status by the U.S. Food and Drug Administration (FDA) on May 28, 2010.


Eisai Oncology

Eisai Oncology is dedicated to discovering, developing and producing innovative oncology therapies that can make a difference and impact the lives of patients and their families. This passion for people is part of Eisai’s human health care (hhc) mission, which strives for better understanding of the needs of patients and their families to increase the benefits health care provides. Our commitment to meaningful progress in oncology research, built on scientific expertise, is supported by a global capability to conduct discovery and preclinical research, and develop small molecules, therapeutic vaccines, biologic and supportive care agents for cancer across multiple indications.

5 comments:

kim said...

Pat,
This was a very interesting article, I am curious especially as I know you have researched breast cancer. Have you heard of the stat that 50% of breast cancer patients will have a recurrance or mets in 15 years?

Patricia Prijatel said...

Kim: I almost cut that part of the article--now I wish I had--as I am not sure where that stat comes from. It is certainly not one I am familiar with. Here's what I think--this puts everybody into one pot, so that the women who have a recurrence within three years are also included. That skews the figures significantly. It also is a worldwide figure, which means treatments--and risk factors-- will vary. And, finally, the worst reason of all, and one reason I hesitate posting these types of news releases--marketing. The company wants to make sure we know there is a market for their product. As if we didn't already. So thanks for questioning it. I should have added a comment about this when I posted it. Or edited it out. Thanks so much for opening the discussion. Pat

kim said...

Pat--Thanks for responding and the clarification. Stats are stats...so I typically take 'em with a grain of salt. I will admit that these caught me a little off guard. I appreciate your thoughts and all the good information you share. Hope your enjoying your summer!

Anonymous said...

Is the 50% figure for all breast cancers, not just TNBC? It was my understanding that TNBC has a better long term prognosis, that the risk of recurrence drops very early, whereas this is not the case for hormone positive breast cancers. I know that TNBC is viewed very negatively, but from many of the statistics I have seen the 5 year disease free survival for early stage TNBC is not too much different from early stage hormone positive cancers. The stat I saw from San Antonio breast cancer abstracts was 86% disease free at 5 years for TNBC vs. 91% disease free for hormone cancers. I wonder what those stats would be at 10 years or 15 years? I am sure the figures get closer together. It makes you wonder what the disease free figures would be for TNBC once there is a targeted therapy in addition to chemo and radiation. I know my surgeon, speaking of breast cancers in general said that metastatic disease was something that occurs at 10-15 years post diagnosis. Could you clarify from this article whether it is talking about all breast cancers?

Patricia Prijatel said...

The 50 percent figure does, indeed, include all types of breast cancer--hormone positive, negative, Her2, inflammatory. The latter two have even worse prognosis than TNBC. You are right, though, that the ten-year prognosis for hormone-negative is better than for hormone-positive, and that the odds do improve after five years. The 15-year figure is thorny, as I have not seen any specific figures for TNBC 15 years post diagnosis. I will do research on that and post what I find.