interferon gamma-1b + azathioprine

**interferon gamma-1b + azathioprine** is a combination therapy consisting of interferon gamma-1b, an immune system activator (recombinant human interferon, typically marketed as Actimmune), and azathioprine, an immunosuppressive purine analogue. Interferon gamma-1b binds to specific receptors on immune cells, modulating signal transduction and enhancing phagocytic and antimicrobial activity, notably approved for chronic granulomatous disease and severe malignant osteopetrosis. Azathioprine is a purine antimetabolite that inhibits DNA synthesis in proliferating cells, reducing the activity and proliferation of T and B lymphocytes, commonly used in organ transplantation and autoimmune disease. The combination has been investigated mainly in multiple sclerosis—especially secondary progressive multiple sclerosis (SPMS) unresponsive to interferon beta, and in idiopathic pulmonary fibrosis (IPF)—to explore synergistic immunomodulation. Mechanistically, this combination simultaneously boosts some aspects of immune response (by interferon gamma-1b) while suppressing overactive or pathogenic immune cells (by azathioprine). The combination may require careful monitoring due to compounded risks of cytopenias and immune modulation[1][5][7][8][9][10].