rituximab + azathioprine

Rituximab + azathioprine is a combination of two immunosuppressive drugs used primarily in the management of autoimmune diseases and certain types of vasculitis. Rituximab is a monoclonal antibody that targets CD20 on B lymphocytes, leading to their depletion through mechanisms such as complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC). This results in reduced autoantibody production and modulation of immune responses[5][8]. Azathioprine is an antimetabolite immunosuppressant that inhibits purine synthesis, thereby suppressing the proliferation and function of both B and T lymphocytes[6]. The combination may be used sequentially or concurrently for induction or maintenance therapy in diseases like pemphigus vulgaris, anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), and other autoimmune conditions. Clinical studies suggest that azathioprine can prolong remission after rituximab induction but may be less effective than continued rituximab for preventing relapse in AAV[2][3]. The combination increases the risk of infections due to additive immunosuppression[1].