LAG-3 is checkpoint inhibitor in cancer that coordinates the down regulation of the proliferation of antigen-specific lymphocytes. There is a great need to discover and develop new therapies focused on inhibiting the action of LAG-3 and consequently improving the immune response in the various types of cancer. Authors of patent US2018271940 propose a method to eradicate cancer that utilizes the combination of LAG-3Ig and anti-PD-1 or anti-PD-L1 antibodies. Areas covered: Patent US2018271940 describes a method consisting of the utilization of either a pharmaceutical cocktail containing LAG-3Ig and an anti-PD-1 or anti-PD-L1 antibody for activation of T cells as a potential for the treatment of cancer. Expert opinion: Data supporting the patent demonstrate the ability of LAG-3Ig and PD-1/PD-L1 to be useful in T cells activation, in addition to the reports showing that LAG-3 and anti-PD-1 and PD-L1 antibodies are therapeutic agents against cancer. Although the proposed methodology is very interesting and promising, further studies are necessary to assess the clinical applicability of the inventions on cancer.