MTG Biotherapeutics' MTG-201 granted FDA Orphan Drug Designation for malignant mesothelioma treatment

MTG Biotherapeutics (MTG), an immuno-oncology company developing novel therapeutics for the treatment of cancer, today announced that the US Food and Drug Administration has granted Orphan Drug Designation for MTG-201, an advanced biologic therapy targeting Dickkopf-3 gene defects in various cancers, for the treatment of malignant mesothelioma. The Dickkopf-3 gene produces a protein called REIC (Reduced Expression in Immortalized Cells protein), which is a critical protein in the downstream mechanism of apoptosis and when absent cancer cells cannot die.

Mesothelioma is a rare, aggressive cancer that most often affects the lining of the pleural cavity. Available treatments for mesothelioma are very limited, particularly for patients with advanced disease. In particular, there is a great need to develop therapies such as MTG-201 that can directly attack the mesothelioma cancer cells and induce the immune system against the cancer, to put in combination with anti-CTLA-4 antibodies now in development for this disease.

"There is a significant need for new treatment options for patients with mesothelioma given this is one of the most aggressive and poorly treated cancers. MTG-201 represents a very novel approach to treating this cancer by selectively inducing apoptosis and inducing an immunologic response against the cancer," said Richard Lowenthal, CEO and President of MTG. "MTG has already demonstrated that ability of MTG-201 to induce selective apoptosis in Phase 1 studies for prostate cancer, another cancer immortalized by hypermethylation of the Dickkopf-3 gene. Mesothelioma has been found to be the most sensitive cancer to this mechanism of action and as such we are moving MTG-201 into Phase 1 development for this indication."

The US Food and Drug Administration Orphan Drug Designation program 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 USA.

MTG-201 is part of a pipeline of immuno-oncology therapies based on REIC protein expression in cancers with hypermethylation of the Dickkopf-3 gene. By expressing REIC protein from within cancer cells, MTG-201 induces selective apoptosis due to ER stress, thus directly killing the cancer and reducing cancer burden. As a result of this selective apoptotic mechanism, MTG-201 also stimulates the production of activated T-cell lymphocytes that specifically target and destroy residual cancer cells. Given this mechanism of action, MTG-201 has the potential to work with checkpoint inhibitors now in development in a highly synergistic manner.

In addition to being investigated as a treatment for patients with mesothelioma, MTG-201 is currently in clinical development for the treatment of prostate cancer. Preclinical programs are ongoing for the treatment of liver (HCC) and bladder cancers.

In the US, under the Orphan Drug Act, the FDA's Office of Orphan Products Development (OOPD) grants orphan drug status to a drug intended to treat a rare disease or condition, which is generally a disease that affects fewer than 200,000 individuals in the country. Upon approval, if received, the designation provides MTG-201 with certain benefits, including seven years of US market exclusivity in the specified indications if the sponsor complies with certain FDA requirements. Additional incentives for the sponsor include tax credits related to qualified clinical trial expenses and a possible exemption from FDA application fees.

SOURCE MTG Biotherapeutics