A therapeutic vaccine is a vaccine which is administered after the disease or infection has already occurred. The therapeutic vaccine works by activating immune system of the patient to fight towards infection. The difference in therapeutic vaccine and vaccine is that vaccines are administered to individuals as a precautionary measure to avoid the infection or disease while therapeutic vaccines are administered after the individual is already affected by the disease or infection. Therapeutic vaccine fights the existing infection in the body rather than immunizing the body for protection against future diseases and infections. The therapeutic vaccines are mostly against viral infections. The patients affected with chronic viral infections are administered with therapeutic vaccines, as their immune system is not able to produce enough efficient antibodies. Provenge, developed by Dendreon, was the first therapeutic vaccine approved by FDA in 2010. This therapeutic vaccine helped in treating prostate cancer where patients' own white blood cells were taken and treated with drug to train them to differentiate and fight cancer cells.
Functionality
The therapeutic vaccines are new form of vaccines that are mostly being used for viral infections and various type of cancers. The therapeutic vaccine helps immune system to recognize a foreign agent such as cancerous cells or a virus. The specific type of therapeutic vaccines includes antigen vaccines. In case of antigen vaccines, the body is introduced to a foreign agent to activate the immune system so that it recognizes the agent when later encountered.
Types
There are two types of therapeutic vaccines which are:
Autologous vaccines
Autologous means that 'derived from oneself' – An autologous vaccine is a personalized vaccine which is made from an individual's own cells which could be either cancer cells or immune system cells.
Allogenic vaccines
Allo means 'other'. Allogenic are majorly cancer vaccines which are made from non-self cancer cells which are grown in a lab.
How therapeutic vaccines are different from vaccines
The concept of therapeutic vaccines is different. When a person hears the word vaccine, the thought of prevention against a certain disease comes into mind. However, therapeutic vaccines are method of treatment. Like any other vaccine, the immune system is regulated against a specific type of target. The main goal is to enhance the immune system activity. This type of vaccine can be employed for the treatment of various type of diseases and viral infections. Efforts are being made to develop vaccines against various fatal diseases such as HIV, cancer, dengue fever, cholera, Diphtheria, etc.
Therapeutic vaccine against HIV
HIV is have no vaccine up til now, but therapeutic vaccine could be the breakthrough for HIV. Such vaccine would enhance affected patients immune system to fight the disease. Many researchers are trying to develop and test therapeutic HIV vaccines in order to slow the HIV progression to AIDS. People affected with HIV normally have HIV at undetectable level, which is detected by use of antiretroviral therapy. If therapeutic vaccine for HIV worked out, it will save many lives. There are many clinical trails being conducted for HIV therapeutic vaccine. Many clinical trials for therapeutic HIV vaccine are conducted by AIDSinfo, summaries for trails are available at their website.
Therapeutic vaccine against cancer
Cancer is the major cause of deaths in the recent era. Cancer types and stages have enhanced with time and so has efforts to treat cancer. Currently, there are about 369 cancer vaccine studies ongoing all around the world. There are three cancer therapeutic vaccines which are approved by USA Food and Drug Administration, as following; Provenge is Sipuleucel-T, a dendritic cell based vaccine for prostate cancer. Bacillus Calmettle-Guerin is a live attenuated vaccine which makes use of Mycobacterium bovis strain for bladder invasive cancer. Talimogene laherparepvec is a vaccine for advanced oncolytic melanoma
