Samarium (¹⁵³Sm) lexidronam (chemical name Samarium-153-ethylene diamine tetramethylene phosphonate, abbreviated Samarium-153 EDTMP, trade name Quadramet) is a chelated complex of a

radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ...

of the

element Element or elements may refer to: Science * Chemical element, a pure substance of one type of atom * Heating element, a device that generates heat by electrical resistance * Orbital elements, parameters required to identify a specific orbit of o ...

samarium Samarium is a chemical element; it has symbol Sm and atomic number 62. It is a moderately hard silvery metal that slowly oxidizes in air. Being a typical member of the lanthanide series, samarium usually has the oxidation state +3. Compounds of s ...

with

EDTMP EDTMP or ethylenediamine tetra(methylene phosphonic acid) is a phosphonic acid. It has chelating and anti corrosion properties. EDTMP is the phosphonate analog of EDTA.Svara, J.; Weferling, N.; Hofmann, T. "Phosphorus Compounds, Organic," In 'Ul ...

. It is used to treat pain when

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

has spread to the

bone A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, ...

. It is injected into a vein and distributed throughout the body, where it is preferentially absorbed in areas where cancer has invaded the bone. The radioisotope ¹⁵³Sm, with a

half-life Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Film * Half-Life (film), ''Half-Life'' (film), a 2008 independent film by Jennifer Phang * ''Half Life: ...

of 46.3 hours, decays by emitting

beta particles A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus, known as beta decay. There are two forms of beta decay, β− decay and � ...

(

electrons The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up qua ...

), which kill the nearby cells. Pain begins to improve in the first week for most people and the effects can last several months. It is commonly used in

lung cancer Lung cancer, also known as lung carcinoma, is a malignant tumor that begins in the lung. Lung cancer is caused by genetic damage to the DNA of cells in the airways, often caused by cigarette smoking or inhaling damaging chemicals. Damaged ...

prostate cancer Prostate cancer is the neoplasm, uncontrolled growth of cells in the prostate, a gland in the male reproductive system below the bladder. Abnormal growth of the prostate tissue is usually detected through Screening (medicine), screening tests, ...

breast cancer Breast cancer is a cancer that develops from breast tissue. Signs of breast cancer may include a Breast lump, lump in the breast, a change in breast shape, dimpling of the skin, Milk-rejection sign, milk rejection, fluid coming from the nipp ...

, and

osteosarcoma An osteosarcoma (OS) or osteogenic sarcoma (OGS) is a cancerous tumor in a bone. Specifically, it is an aggressive malignant neoplasm that arises from primitive transformed cells of mesenchyme, mesenchymal origin (and thus a sarcoma) and that exhi ...

Side effects

Side effects include the following: *Black, tarry stools *Blood in urine/stool *Cough, hoarseness *Fever/chills *Lower back/side pain *Painful or difficult urination *Pinpoint red spots on skin *Irregular heartbeat *Nausea, vomiting

Supply and administration

Samarium lexidronam is supplied as a frozen solution for intravenous use with an activity of 50±5 mCi/mL on Quadramet. 2009. and a maximum beta energy of 0.808

MeV In physics, an electronvolt (symbol eV), also written electron-volt and electron volt, is the measure of an amount of kinetic energy gained by a single electron accelerating through an electric potential difference of one volt in vacuum. When us ...

. Due to the short half-life of the radioisotope, the drug expires 56 hours after the noted calibration time.

References

Radiopharmaceuticals Samarium compounds Phosphonates Coordination complexes Tertiary amines {{pharma-stub