These are the drugs that directly affects our immune system. It kills the B cells and T cells are key cells involved in bodys defence system . They may block the molecules secreted by these cells which are responsible for causing inflammation. These drugs have revolutionised the treatment of autoimmune disease and are like the “ Brahmashtra” in treatment of auto immune disease. But due to its high price it is not accessible to the common man. A patient might have to spend Rs.30-40 thousands rupees per month to get these drugs. Therefore bio-similars have been introduced which are similar to biologic and available at much cheaper price.