The 2010 CTRC-AACR San Antonio Breast Cancer Symposium is presented by Cancer Therapy & Research Center at UT Health Science Center San Antonio, the American Association for Cancer Research, and Baylor College of Medicine. The prestigious event will be held between December 8-12, and brings together the top cancer researchers from around the world.
At this year's event, unexpected new data will be presented from the Phase II study of the AE37 HER2/neu Peptide Vaccine for early stage breast cancer patients will be presented by researchers from the United States Military Cancer Institute. The Phase II study is a prospective, randomized, multi-center clinical trial investigating whether the AE37 Vaccine can prevent recurrence in disease-free, conventionally treated, node-positive and high-risk node-negative breast cancer patients who are at significant risk for recurrence. Generex is collaborating with the USMCI in this exciting study.
The data is unexpected, since we are currently unaware of any clinical work where the AE37 Vaccine is given to early stage breast cancer patients either sequentially or concurrently with Herceptin. The researchers at the USMCI have been conducting preliminary work to assess any advantage in a combination immunotherapy with Herceptin and HER2/neu peptide-based vaccines (see here). However, these efforts apeared to focus more on the first generation E75 Peptide Vaccine and the second generation AE37 Peptide Vaccine was not mentioned. In previous blogs, I have speculated that Herceptin used with AE37 may make Herceptin more potent. My theory came from reading available abstracts that evaluated the therapeutic role Herceptin has in "modulating the activity of the cellular immune system in patients with breast cancer". I borrowed that quote from a peer review that appeared in the British Journal of Cancer. The report is titled The Effects of Trastuzumab (Herceptin) on the CD4+CD25+FoxP3+ and CD4+IL17A+ T-cell Axis in Patients with Breast Cancer. The concluding sentence of the report states that "the coadministration of trastuzumab along with therapies that either promote Th17 or reduce Treg cells may be a particular direction, with the aim of ultimately improving the prognosis for patients unresponsive to trastuzumab or other therapies".
We learned from an abstract presented at ASCO 2010 that the AE37 Vaccine is reducing the levels of Treg cells (see here). The conclusion of the abstract stated that the "AE37 + GM-CSF vaccine decreases Tregs during and after completion of vaccination while GM-CSF alone does not alter Treg levels. This suggests that AE37 may allow the immune system to more effectively fight cancer and correlates with an observed decrease in recurrences." I suppose the USMCI also looked at that AE37 data and recognized the potential for combining AE37 either sequentially or concurrently with Herceptin. The title of the unexpected abstract at this year's SABCS Annual Meeting is Combination Immunotherapy for Breast Cancer Patients: Safety and Immunologic Data from a Phase II Trial Administering a HER2/neu-Derived Peptide vaccine (AE37+GM-CSF) Sequentially or Concurrently with Trastuzumab in the Adjuvant Setting. Trastuzumab = Herceptin. Click on the title for the link to view Poster Sessions 2 Treatment and scroll down to "Therapeutic Strategies: Immunotherapy Clinical" and circle December on your GNBT calender. Generex Oncology, aka Antigen Express, is on the cusp of developing a targeted immunotherapeutic vaccine that may revolutionize how cancer is treated in the near future.
