Xofigo is a radiopharmaceutical ( a medicine containing a radioactive substance ) that contains the active substance Radium-223 dichloride. It is used to treat adult men with cancer of the prostate. Xofigo is used when medical or surgical castration ( stopping the production of male hormones in the body using medicines or surgery ) does not work, and when the cancer has spread to the bones and is causing symptoms such as pain but is not known to have spread to other internal organs.
Xofigo is available as a solution for injection. The dose of Xofigo is calculated based on the patient’s body weight to provide a specific dose of radioactivity ( 50 kilobecquerels per kilogram body weight – a kilobecquerel is a measure of radioactivity ). The medicine is given into a vein by slow injection usually lasting around one minute. Injections are repeated every 4 weeks for a total of 6 injections.
The active substance in Xofigo, Radium-223, emits short-range radiation known as alpha particles. In the body, radium is handled like the calcium naturally found in the bones. It accumulates in bone tissues where the cancer has spread, and the alpha particles destroy surrounding cancer cells and help to control the associated symptoms.
Xofigo was compared with placebo as an addition to standard care in a main study involving 921 men with cancer of the prostate that had spread to the bones and for which suppression of male hormones using medicines or surgery did not work. Patients were given up to 6 injections at 1-month intervals and were followed up for 3 years from the first injection. The main measure of effectiveness was how long the patients survived. The average survival in patients given Xofigo was 14.9 months, compared with 11.3 months in those given placebo. Patients given Xofigo also took longer for signs and symptoms of progressive disease such as fractures and bone pain to develop.
The most common side effects with Xofigo ( which may affect more than 1 in 10 people ) are diarrhoea, nausea, vomiting and thrombocytopenia. The most serious effects were thrombocytopenia and neutropenia.
Xofigo had shown a clinically relevant benefit in prolonging life and delaying signs and symptoms of progressive disease. Its main short-term side effects were reversible and considered manageable. The radiation emitted by Xofigo has a shorter range than the radiation of currently available radiopharmaceuticals. This may limit the damage to nearby healthy tissues. ( Xagena )
Source: European Medicines Agency ( EMA ), 2013