Cancer is a primary leading disease for mortality in the world. Immunotherapy is the latest trend for curing cancer and thus biopharmaceutical industry has developed a keen interest and manufactured several drug products such as monoclonal antibodies for immunotherapy. Programmed Cell Death Protein 1 (PD-1) evades immune response and promotes self-tolerance by modulating the activity of T-cells, activating apoptosis of antigen-specific T cells, and inhibiting apoptosis of regulatory T-cells. On the other hand, Programmed Cell Death Ligand 1 (PD-L1) is a trans-membrane protein and it’s a co-inhibitory factor of the immune response1. Cancer Immunotherapy has been designed to increase the specificity and strength of the immune system against cancer. James P. Allison and Tasuku Honjo won the 2018 Nobel Prize for Physiology or Medicine for discovering a cancer treatment by suppressing negative immunomodulation.