MANHASSET, NY -- The Institute for Medical Research of the North Shore-Long Island Jewish (LIJ) Health System today announced that it has received approval from the U.S. Food and Drug Administration (FDA) to manufacture a drug used for diagnostic imaging with positron emission tomography (PET), a scanning technique that generates internal pictures of the human body at work.
The Institute's cyclotron/radiochemistry facility in Manhasset, NY, is the third institution in the United States approved by the FDA to manufacture Fludeoxyglucose F 18 injection, and the only one approved to make it at the highest strength currently available. It is twice the strength of the second institution's drug, and five times the strength of the first, which is no longer on the market.
Because radiopharmaceuticals like Fludeoxyglucose F 18 decay rapidly, they must be used right away. However, the necessity to produce them in a hospital setting and then use them immediately poses a potential safety issue. If Fludeoxyglucose F 18 is contaminated by microorganisms, other chemicals, byproducts or impurities, it may affect the quality of the PET scan result and also pose a danger to patients. Therefore, manufacturing radiopharmaceuticals in a controlled environment that operates under rigorous quality assurance standards is key to safe production.
"The FDA is in the process of instituting regulatory control over the manufacture of radiopharmaceuticals used in PET scanning such as Fludeoxyglucose F 18 to ensure safety to patients and the use of highly controlled manufacturing practices," said Thomas Chaly, PhD, chief of the Institute's cyclotron/radiochemistry facility and the author of its new drug application to the FDA. Regulation is expected within the next few years, he said. FDA approval to manufacture a radiopharmaceutical depends not only on the success of the actual application but a site visit and inspection by the FDA of the facilities, equipment and procedures used in the manufacture of the drug.
Fludeoxyglucose F 18 is the most widely used radiopharmaceutical in PET scanning. A radiopharmaceutical is a specially designed drug that consists of a molecular compound that is similar to one normally used by cells -- in this case, glucose -- but which is tagged with radioactive atoms. When the cell absorbs the radiopharmaceutical, gamma rays are released as the unstable radioactive atoms rearrange themselves into a stable configuration. Traveling at the speed of light, the gamma rays allow the PET camera to generate a picture of those cells and organs at work. The amount of radiation to which a person is exposed is minimal and compares to that of a basic X-ray or CT scan.
Radioactive fluorine atoms are produced by a cyclotron, like the state-of-the-art GE PETrace Cyclotron purchased by North Shore-LIJ last year and installed at its research institute at a total cost of $2.6 million. It is the only cyclotron on Long Island used to produce radiopharmaceuticals for both research and clinical PET scanning. Once the radioactive atoms are produced, a sophisticated radiochemistry instrument such as a Fludeoxyglucose synthesizer incorporates the radioactive atoms into a chemical compound such as deoxyglucose and produces the drug. Fludeoxyglucose F 18 is manufactured in a saline solution, stored in glass vials and injected intravenously just prior to the actual PET scanning procedure.
The speed of radioactive decay of Fludeoxyglucose F 18, or its half-life, is just under two hours. This means that every two hours, half of its radiation-emitting ability is lost. Therefore, the drug must be used the same day it is manufactured, often within just hours of production -- creating a challenge for transporting the drug over any distance. The drug strength produced depends on the capacity of the cyclotron. The greater the strength that can be made, the more drug is available for PET imaging studies and the farther the distance it can travel and still be active.
North Shore-LIJ currently sells and distributes Fludeoxyglucose F 18 to numerous hospitals and PET facilities in the New York metropolitan area at about 40 percent of its capacity. The high strength permits distribution as far away as Washington, DC. With FDA approval ensuring quality assurance and safety to doctors who prescribe diagnostic PET scans for their patients, North Shore-LIJ expects demand for its drug to increase.
Fludeoxyglucose F 18 is currently approved for use in the United States in the diagnosis of cancer, epileptic seizures and heart viability to determine, after a heart attack, if the heart muscle would benefit from surgery. "Because Fludeoxyglucose F18 injection is a drug, it needs to be prescribed by a physician," said Dr. Chaly, "and physicians can actually write the prescription for 'FDA-approved Fludeoxyglucose F18 injection'."
Source: Eurekalert & othersLast reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
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