Iodine CC49 is an iodine-125

Iodine-125

Iodine-125 is a radioisotope of iodine which has uses in biological assays, nuclear medicine imaging and in radiation therapy as brachytherapy to treat prostate cancer and brain tumors. It is the second longest-lived radioisotope of iodine, after iodine-129.Its half-life is around 59 days and it...

 radiolabelled monoclonal antibody for the detection of tumours. It is used in radioimmunoassay

Radioimmunoassay

Radioimmunoassay is a very sensitive in vitro assay technique used to measure concentrations of antigens by use of antibodies...

s like CA 72-4.

CC49 has also been tested for the treatment of solid tumours, but without success. Iodine (¹³¹I

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...

) CC49 and lutetium (¹⁷⁷Lu) CC49, for example, were shown to induce human anti-mouse antibodies; no tumour response was observed in Phase I and II trials.

Derivatives

A wide range of CC49 derivatives has been used in pharmaceutical research. Examples include chimeric and humanized CC49, as well as a fusion protein

Fusion protein

Fusion proteins or chimeric proteins are proteins created through the joining of two or more genes which originally coded for separate proteins. Translation of this fusion gene results in a single polypeptide with functional properties derived from each of the original proteins...

 of a CC49 single-chain variable fragment and the enzyme beta-lactamase

Beta-lactamase

Beta-lactamases are enzymes produced by some bacteria and are responsible for their resistance to beta-lactam antibiotics like penicillins, cephamycins, and carbapenems . These antibiotics have a common element in their molecular structure: a four-atom ring known as a beta-lactam...

.