Immunmodulators

Immunomodulators are substances and drugs that alter the immune response. They can enhance immune activity (immunostimulants) or suppress it (immunosuppressants), and may selectively adjust specific immune pathways. They include endogenous mediators such as cytokines as well as exogenous agents such as small molecules, antibodies, and cellular therapies. They are used to treat a variety of conditions in which the immune system plays a central role.

Broad categories of immunomodulators include immunostimulants (cytokines like interferons and interleukins, immune adjuvants, and some vaccines), immunosuppressants (glucocorticoids, calcineurin inhibitors, mTOR inhibitors, cytotoxic drugs), and targeted immunotherapies (checkpoint inhibitors such as PD-1/PD-L1 and CTLA-4 inhibitors; immunomodulatory drugs like thalidomide analogs; monoclonal antibodies; and cell-based therapies such as CAR-T cells). In cancer, immunomodulation aims to enhance anti-tumor immunity, while in autoimmune diseases it focuses on dampening aberrant immune responses.

Immunomodulators act on various components of the immune system, including T cells, B cells, macrophages, and dendritic cells, influencing cytokine production, cell activation, or antigen presentation. They have clinical applications across oncology, rheumatology, dermatology, gastroenterology, infectious diseases, and transplantation. Examples include checkpoint inhibitors such as pembrolizumab and nivolumab, immunomodulatory drugs like lenalidomide, interferon therapy, corticosteroids, and mTOR or other pathway inhibitors.

Safety and regulatory considerations are important, as immunomodulation can increase infection risk, provoke hypersensitivity or autoimmune complications, or cause organ toxicity. The field continues to evolve with research into combination regimens, predictive biomarkers, and new targets to refine efficacy and safety.