On 20 September 2010, orphan designation was granted by the European Commission for Vorinostat for the treatment of malignant mesothelioma.
Malignant mesothelioma is a cancer that is usually caused by exposure to asbestos. It affects the lining of organs, mainly the pleura and the peritoneum.
Mesothelioma of the pleura causes difficulty breathing and chest pain, and mesothelioma of the peritoneum causes ascites and abdominal pain.
Because the symptoms are not specific, the cancer is often detected at a late stage.
Malignant mesothelioma is a life-threatening disease because patients have very poor survival, only living for a year, on average, after diagnosis.
At the time of designation, malignant mesothelioma affected approximately 0.6 in 10,000 people in the European Union ( EU ). This was equivalent to a total of around 30,000 people, and is below the threshold for orphan designation, which is 5 people in 10,000.
At the time of designation, the main treatment for malignant mesothelioma was surgery followed by chemotherapy or radiotherapy.
If the disease was too advanced for surgery, chemotherapy was used on its own. One medicine, Pemetrexed, was authorised in the EU for the treatment of malignant pleural mesothelioma.
The sponsor ( MSD ) has provided sufficient information to show that Vorinostat might be of significant benefit for patients with malignant mesothelioma because it works in a different way to existing treatments and because it might be able to be used in patients who have already been treated with other anticancer medicines or in combination with other anticancer medicines. These assumptions will need to be confirmed at the time of marketing authorisation, in order to maintain the orphan status.
Vorinostat blocks the activity of proteins called histone deacetylases, which are involved in turning genes on and off within cells. The exact way that Vorinostat works in malignant mesothelioma is not known, but it is expected to act on genes, enzymes and growth factors, leading to a reduction in the growth and division of the cancer cells. ( Xagena )
Source: EMA, 2013