Types of Immunotherapy
Immunotherapy is a treatment applied to the body to treat a disease by boosting or suppressing the immune system. The treatment is divided into two categories, activation immunotherapy, and suppression immunotherapy. Some of the types of immunotherapy available today include CAR T-cell therapy, Bacillus Calmette-Guerin (BCG), Monoclonal antibodies, and Cytokine therapy.
CAR T-cell therapy
CAR T-cell immunotherapy is an effective cancer treatment that helps patients achieve complete remission. This is especially useful when other therapies, such as chemotherapy, fail.
This therapy involves infusing a genetically altered T cell into the body through an IV. The T cells circulate the cancer cells and kill them. A short course of chemotherapy is given beforehand to ensure the regular immune system accepts the CAR T cells.
Typically, this type of therapy is used to treat multiple myeloma. Although it is a life-saving treatment, it can lead to non-response and severe side effects.
Cytokine therapy
The cytokine-based immunotherapy of cancer has been a highly successful treatment method. Cytokines have been studied as an adjuvant to cancer therapies and to enhance the survival of antigen-specific TILs and CAR cells. These strategies, which may also be helpful in tumor immunosurveillance, have yet to provide a breakthrough in improving the therapeutic index. However, results are eagerly anticipated as more research continues on cytokines’ biology.
Cytokines are small molecules produced by a variety of immune cells. They play an essential role in regulating the balance of the immune system. Their actions include:
- Stimulating the infiltration of tumor-specific lymphocytes.
- Enhancing the proliferation of tumor-specific cells.
- Modifying the differentiation of both antigen-presenting and effector cells.
Non-specific immunotherapy
Non-specific immunotherapy, also known as immune system modulators, boosts the body’s immunity and helps it fight off attackers. It is a treatment that may be beneficial for many conditions. However, there are some potential downsides to using it.
Some of the side effects of immunotherapy include hepatitis, diarrhea, itching, and muscle pain. However, many patients find that the benefits of treatment outweigh the risks.
Immunotherapy can treat autoimmune diseases, allergies, and certain types of cancer. Generally, it is combined with chemotherapy. In addition, a few new therapies are being developed. These include interferon and interleukin-2.
Monoclonal antibodies
Monoclonal antibodies are immune system proteins genetically engineered to bind to a specific target. They have been approved for the treatment of a variety of cancers. This therapy can bring T cells close to cancer cells, helping destroy them. However, it can also cause side effects.
The use of monoclonal antibodies in immunotherapy has evolved over the past two decades. It has enabled the development of better bio therapeutics. As a result, the global market for monoclonal antibodies is expected to experience steady growth.
In recent years, the development of bispecific immunotherapeutics has also become a focus of research. Bispecifics, also known as polyspecific, can engage multiple epitopes at the same time.
Bi-specific T-cell engagers
Bispecific T-cell engagers for immunotherapy (BiTEs) are a novel treatment approach that targets tumor-specific antigens while at the same time promoting T-cell activation. The BiTE molecule binds the T-cell receptor (TCR) and the tumor-specific antigen on the tumor cell simultaneously.
TCEs are highly effective and can treat cancer patients without undergoing chemotherapy. However, there is a need to design molecules with a broad therapeutic window and long half-life, and the safety concerns associated with protein aggregates are also essential considerations.
As a result of the many different BiTE molecules currently in development, there are numerous options for treating hematologic malignancies. Several have been approved, and several others are now in clinical trials. These include the SKBR3 HER2+ cell line. In addition, Blinatumomab, a canonical CD3/CD19 BiTE, was approved in December 2014 for treating acute lymphoblastic leukemia. It has shown tremendous response rates and could be used with other immunotherapy modalities.
Bacillus Calmette-Guerin (BCG)
Intravesical Bacillus Calmette-Guerin (BCG) immunotherapy is a well-established adjuvant treatment for bladder cancer. It is the gold standard for managing intermediate- and high-risk non-muscle invasive bladder cancers. Although many patients experience recurrence, the overall incidence of disease progression is low. Moreover, the median time to recurrence is insufficient in those treated with intravesical BCG therapy than in those who receive TUR alone. However, reproduction occurs in up to 50% of patients in the first five years after treatment.
Bacillus Calmette-Guerin, or BCG, is a live, attenuated strain of Mycobacterium Bovis. The bacterium is used in vaccines in many developing countries where tuberculosis is high.