Trial Information

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.

Prevnar is designed to augment T-helper cell immunity.