Tositumomab is a drug for the treatment of follicular lymphoma

Follicular lymphoma

Follicular lymphoma is the most common of the indolent non-Hodgkin's lymphomas, and the second most common form of non-Hodgkin's lymphomas overall. It is defined as a lymphoma of follicle center B-cells , which has at least a partially follicular pattern...

. It is a IgG2a anti-CD20

CD20

B-lymphocyte antigen CD20 or CD20 is an activated-glycosylated phosphoprotein expressed on the surface of all B-cells beginning at the pro-B phase and progressively increasing in concentration until maturity....

 monoclonal antibody derived from immortalized mouse cells.

Tositumomab is applied in a sequential infusion followed by iodine (¹³¹I) tositumomab, which is the same antibody covalently bound to the radionuclide

Radionuclide

A radionuclide is an atom with an unstable nucleus, which is a nucleus characterized by excess energy available to be imparted either to a newly created radiation particle within the nucleus or to an atomic electron. The radionuclide, in this process, undergoes radioactive decay, and emits gamma...

 iodine-131

Iodine-131

Iodine-131 , also called radioiodine , is an important radioisotope of iodine. It has a radioactive decay half-life of about eight days. Its uses are mostly medical and pharmaceutical...

 (¹³¹I). ¹³¹I emits both beta and gamma radiation and decays with a half-life

Half-life

Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...

 of 8 days.

Clinical trials have established the efficacy of the tositumomab/iodine (¹³¹I) tositumomab regimen in patients with relapsed or chemotherapy

Chemotherapy

Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....

/rituxan refractory

Refractory

A refractory material is one that retains its strength at high temperatures. ASTM C71 defines refractories as "non-metallic materials having those chemical and physical properties that make them applicable for structures, or as components of systems, that are exposed to environments above...

 follicular lymphoma.

This drug combination is manufactured by Corixa

Corixa

Corixa was a biotechnology/pharmaceutical company based in Seattle, Washington involved in the development of immunotherapeutics to combat autoimmune diseases, infectious diseases, and cancer. It was founded in 1994...

 (now GlaxoSmithKline

GlaxoSmithKline

GlaxoSmithKline plc is a global pharmaceutical, biologics, vaccines and consumer healthcare company headquartered in London, United Kingdom...

). It sells in the U.S. under the trade name Bexxar.

Bexxar was developed by Dr. Mark Kaminski and Dr. Richard Wahl.

There is some evidence that it may cause a smaller decrease in platelet

Platelet

Platelets, or thrombocytes , are small,irregularly shaped clear cell fragments , 2–3 µm in diameter, which are derived from fragmentation of precursor megakaryocytes.  The average lifespan of a platelet is normally just 5 to 9 days...

 counts than ibritumomab tiuxetan

Ibritumomab tiuxetan

Ibritumomab tiuxetan, sold under the trade name Zevalin, is a monoclonal antibody radioimmunotherapy treatment for some forms of B cell non-Hodgkin's lymphoma, a lymphoproliferative disorder and thus affects the lymphatic system...

does.

External links

• Bexxar regimen entry in the public domain NCI Dictionary of Cancer Terms