Nivolumab and ipilimumab are immune checkpoint inhibitors (for PD-1 and CTLA-4), this is meant to increase/maintain the activation of immunized T cells, as liga

Nivolumab and ipilimumab are immune checkpoint inhibitors (for PD-1 and CTLA-4), this is meant to increase/maintain the activation of immunized T cells, as ligands of these checkpoint receptors are often expressed by the cancer cells (or more generally the cells in the cancer microenvironment) which attempt to attenuate the immune response directed at them. So this is effectively a fancy cancer vaccine adjuvant. The vaccine itself targeting telomarase is interesting, but not without limitations. Immunized T cells can only 'see' telomarase (which is inside the cell) if bits of it are presented on the cancer cell surface via MHC molecules (which is what they are for - to provide a 'window' into the cell for the immune system to peek through). Cancer cells predictably shed MHC molecules in an attempt to hide. Another angle is that telomerase can be transiently activated in rapidly proliferating cells (most notably... lymphocytes). So there may be some on-target off-cancer effects. Another difficulty is that T cells in general have a hard time getting into solid tumors in sufficient numbers (unless additional measures are taken). (I am a biologist who works in CAR-T development)