THERAPEUTICS

Brands

• Rituxan, MabThera, Zytux

Generic?

• No

Class

• Immunosuppressant

Commonly Prescribed for

(FDA approved in bold)

• CD20-positive chronic lymphocytic leukemia

• Wegener's granulomatosis

• Microscopic polyangiitis

• CD20-positive B-cell non-Hodgkin lymphoma (NHL)

• Rheumatoid arthritis

• Myasthenia gravis (MG)

• Multiple sclerosis (MS) (relapsing-remitting)

• Multifocal motor neuropathy

• Anti-myelin-associated glycoprotein (MAG) neuropathy

• Chronic inflammatory demyelinating polyneuropathy (CIDP)

• Neuromyelitis optica

• Dermatomyositis

• Stiff-person syndrome

• Primary CNS lymphoma

• Anti-NMDA-receptor encephalitis

• Opsoclonus myoclonus

• Sarcoidosis

• Waldenstrom macroglobulinemia

• Immune thrombocytopenic purpura

• Lupus nephritis

How the Drug Works

• Binds to the CD20 antigen on pre-B and mature B lymphocytes, inducing apoptosis. The antigen is expressed in greater than 90% of B-cell NHL but not on stem cells, pro-B cells, plasma cells, or normal tissues. B cells are felt to be important in the pathogenesis of rheumatoid arthritis, MS, MG, and many other autoimmune diseases

• Rituximab may also decrease other biological markers of inflammation, such as C-reactive protein, serum amyloid protein, and rheumatoid factor

How Long Until It Works

• By 2 weeks, but effect on disease may take months

If It Works

• May allow reduction in dose or discontinuation of corticosteroids or other agents in the treatment of MG, MS, or other neurological conditions

If It Doesn't Work

• Usually used as an adjunctive agent in conjunction with corticosteroids or other agents in MG, but other agents such as azathioprine, mycophenolate mofetil, and cyclosporine are often used instead. In MS, used as an alternative to other agents for refractory relapsing-remitting patients

Best Augmenting Combos for Partial Response or Treatment-Resistance

• Often combined with prednisone or other corticosteroids for treatment of MG, allowing eventual decrease in dose. Occasionally combined with other immunosuppressive agents for many autoimmune diseases, but AEs may increase

Tests

• Obtain CBC before beginning and during therapy, more frequently if patient develops cytopenia