What is Biological therapy in Cancer?
Biological therapy is the use of drugs that target specific areas of the Cancer cell and its environment. Over the last 15 years or so, there has been a significant increase in the use of biological agents in the treatment of Cancer. Biological therapy includes a vast number of treatments including angiogenesis inhibitors, monoclonal antibodies, immunotherapy, gene therapy, vaccine therapy, cytokine therapy and targeted drug therapy.
Biological therapies can be broadly divided into two groups “nibs” and “mabs”
“nibs” are agents that target specific receptors in the cancer cell pathway and stop the cancer cells from dividing and increasing. Normally the cancer grows and develops using specific pathways. These pathways are present in the growth of normal cells in the body too, but some cancers develop processes to amplify these pathways allowing them to grow faster. These drugs have names that end with “nib”. Examples include Sunitinib, Sorafenib, Erlotinib etc.
“mabs” are types of drugs which again target specific areas in the cancer cell or its pathways. Mabs are antibodies developed against specific targets in these areas. There are different types of mabs working in different areas of the Cancer pathways. Some of the common mabs used include Rituximab, Bevacizumab, Trastuzumab etc.
The below picture shows some of the pathways present in the cell that the cancer and normal cells use to grow in size and increase in number. Biological drugs act on specific areas in the pathway, blocking it.
Other biological agents acting on different parts of the cancer pathways include “mibs”, for example Bortezomib and Carfilzomib used in Myeloma.
Do biological therapies produce less side effects than Chemotherapy?
By and large biological treatments have fewer side effects than Chemotherapy as they act on specific targets in the cell. However, they do have side effects and some of them can have serious side effects. So, it is not safe to assume that these drugs are not toxic. The same care and attention should be given to patients on these drugs as is given to those on Chemotherapy.
Can biological therapies be used instead of chemotherapy?
In some situations, there is a choice between Chemotherapy and a Biological agent. In others, there is benefit of using both treatments. So, which treatment to use depends on the type of Cancer, its stage, the presence of certain genetic changes in the cancer cell, the cost of treatment and the fitness of the patient.
Are biological therapies more expensive than Chemotherapy?
The cost of biological therapies varies depending on the drug used and the country in which it is used. Some biological drugs are not expensive, but others can be very expensive. By and large, on average biological therapy can be more expensive than chemotherapy.
How are Biological agents given?
Biological agents are present in tablet and injection forms. Those in injection form are given through the vein or under the skin. Tablet forms are taken by mouth.
How often are they given?
Some drugs particularly tablets are given on a daily basis. Others are given once every week to once every 3-4 weeks.