A Study of hTERT/Survivin Multi-peptide Vaccine With Daclizumab and Prevnar for Patients With Metastatic Breast Cancer

Patients with advanced breast cancer may often fail standard of care treatments for metastatic disease. This research is studying a combinations of agents that impact the immune system.

About >85% of all human cancers, including breast cancer, express telomerase (hTERT) activity. Targeting hTERT immunologically may also minimize immune escape due to antigen loss because mutation or deletion of hTERT may be incompatible with sustained tumor growth. hTERT Multi-Peptide Vaccine is made up of 1540 hTERT peptide and cryptic peptides selected for "low-affinity" binding to HLA-A2 in order to increase the likelihood that the host immune system would ignore them, and then they have been modified by changing the first amino acid of the peptides to tyrosine in order to increase HLA - A2 affinity. The two "heteroclitic" peptides are R572Y (YLFFYRKSV) and D988Y (YLQVNSLQTV), which bind HLA-A2 with high avidity and elicit specific CTL (cytotoxic T lymphocyte) responses using healthy donor mononuclear cells in vitro. In addition, in mouse models, these peptide vaccines elicit lytic CTL responses which are protective against tumor challenges using a TERT-expressing murine tumor.

Subjects will also be immunized with a peptide vaccine derived from survivin, an important anti-apoptotic protein which is overexpressed in a broad range of malignancies including breast cancer. Survivin may be an ideal and "universal" tumor antigen since it is overexpressed in a wide variety of cancers yet terminally differentiated adult cells do not express the protein.

CMV derived CTL epitopes will be used as positive control peptides.

Daclizumab is a humanized anti-human CD25 monoclonal antibody that binds specifically to CD25 expressing cells, including Treg cells, and inhibits its proliferation.