AstraZeneca announced that the US Food and Drug Administration has granted Orphan Drug Designation for the anti-CTLA-4 monoclonal antibody, tremelimumab, for the treatment of malignant mesothelioma.

Mesothelioma is a rare, aggressive cancer that most often affects the lining of the lungs and abdomen. Available treatments for mesothelioma are very limited, particularly for patients with advanced disease.

“There is a significant need for new treatment options for patients with mesothelioma because fewer than five percent of patients currently survive beyond five years, even when they receive timely diagnosis and care. Our aim is to rapidly advance the development of tremelimumab as a potential new treatment option for these patients,” said Robert Iannone, senior vice president, head of immuno-oncology, global medicines development at AstraZeneca.

The Orphan Drug Designation programme provides orphan status to drugs and biologics, which are defined as those intended for the safe and effective treatment, diagnosis or prevention of rare diseases or disorders that affect fewer than 200,000 people in the US.

Tremelimumab is part of the broad pipeline of immuno-oncology assets being developed by AstraZeneca and its biologics research and development arm, MedImmune, which are designed to harness the body’s own immune system to fight cancer. It is a fully human monoclonal antibody, which stimulates the immune system to destroy cancer cells through binding to the protein CTLA-4, expressed on the surface of activated T-lymphocytes.

In addition to being investigated as a monotherapy treatment for patients with mesothelioma, tremelimumab is currently being studied in combination with AstraZeneca’s anti PD-L1 investigational immunotherapy, MEDI4736, in tumour types including non-small cell lung cancer and head and neck cancer. It is also being studied in combination with Iressa (gefitinib) in EGFR mutated non-small cell lung cancer and with MEDI6469 (a murine OX40 agonist) in solid tumours.