Denileukin diftitox (trade name Ontak) was an antineoplastic agent, an engineered protein combining

interleukin-2 Interleukin-2 (IL-2) is an interleukin, a type of cytokine signaling molecule in the immune system. It is a 15.5–16 kDa protein that regulates the activities of white blood cells (leukocytes, often lymphocytes) that are responsible fo ...

and

diphtheria toxin Diphtheria toxin is an exotoxin secreted by '' Corynebacterium diphtheriae'', the pathogenic bacterium that causes diphtheria. The toxin gene is encoded by a prophageA prophage is a virus that has inserted itself into the genome of the host ...

. Denileukin diftitox could bind to interleukin-2 receptors and introduce the diphtheria toxin into cells that express those receptors, killing the cells. In some

leukemia Leukemia ( also spelled leukaemia and pronounced ) is a group of blood cancers that usually begin in the bone marrow and result in high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or ' ...

s and

lymphoma Lymphoma is a group of blood and lymph tumors that develop from lymphocytes (a type of white blood cell). In current usage the name usually refers to just the cancerous versions rather than all such tumours. Signs and symptoms may include enlar ...

s, malignant cells express these receptors, so denileukin diftitox can target these. In 1999, Ontak was approved by the

U.S. Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...

(FDA) for treatment of

Cutaneous T-cell lymphoma Cutaneous T-cell lymphoma (CTCL) is a class of non-Hodgkin lymphoma, which is a type of cancer of the immune system. Unlike most non-Hodgkin lymphomas (which are generally B-cell-related), CTCL is caused by a mutation of T cells. The cancerous ...

(CTCL). There is some evidence tying it to vision loss, and in 2006 the FDA added a

black box warning In the United States, a boxed warning (sometimes "black box warning", colloquially) is a type of warning that appears on the package insert for certain prescription drugs, so called because the U.S. Food and Drug Administration specifies that it ...

to the drug's label. In 2014, marketing of Ontak was discontinued in the US.

References

External links

FDA Safety Alert
Antineoplastic drugs Diphtheria {{antineoplastic-drug-stub