GtoPdb Ligand ID: 6781

Synonyms: Bexxar® | V10XA53
tositumomab is an approved drug (FDA (2003))
Compound class: Antibody
Comment: Tositumomab was used as a radioimmunotherapy drug, targeting CD20 on B-lymphocytes prior to cessation of its manufacture.
No information available.
Summary of Clinical Use
Tositumomab was used to treat CD20 positive follicular non-Hodgkin's lymphoma. It was granted orphan drug designation by the EMA for use to treat follicular lymphoma in 2003.
Unfortunately GlaxoSmithKline, the drug's manufacturer ceased production and sales of tositumomab in early 2014. The drug was clinically highly efficacious, but confounding market-driven factors lead to its commercial failure. Initial regulatory delays, manufacturing problems (on the radioactive component side), strong competition (new types of drugs for non-Hodgkin's lymphoma coming through the development pipeline, eg bendamustine), insufficient reimbursement by medical insurers and issues around physician referral patterns all influenced the decision to withdraw this drug from the market.
Mechanism Of Action and Pharmacodynamic Effects
Anti-CD20 monoclonal antibody which is labelled with radio-iodine (131I) to form a radiotherapy drug. Antibody binding to mature B lymphocytes appears to induce apoptosis, complement-dependent cytotoxicity and cell death through ionizing radiation..