Gene Therapy Business
With the aim of commercialization, Takara Bio uses biotechnologies developed over many years to advancethe clinical development of gene therapies that target diseases such as cancer and AIDS.
Takara Bio is currently engaged in the clinical development of the following gene therapies.
Production of vectors
1. HF10 Anti-Cancer Therapy
Takara Bio acquired the HF10 business from M's Science Corporation in November 2010. HF10 is a spontaneously-occurring attenuated mutant strain of herpes simplex virus type 1 (HSV-1) that shows strong antitumor activity when locally injected into tumors. These kinds of viruses are called oncolytic viruses.
Oncolytic viruses selectively replicate inside, and destroy, tumor tissue without excessively damaging normal tissue. Many oncolytic viruses are produced via gene recombination or foreign gene insertion, but HF10 is a spontaneously-mutated virus that does not contain any foreign genes.
In the United States, Phase I clinical trials targeting solid cancers have been completed and Phase II clinical trials targeting malignant melanoma are now underway.
In Japan, clinical research targeting solid cancers has been underway since December 2011 by the Mie University Hospital, while clinical research targeting pancreatic cancer in combination with existing anti-cancer drugs has been underway since April 2013 by the Nagoya University Hospital. Preparations are also being made to begin conducting Phase I clinical trials in fiscal 2015 for patients with solid cancers in Japan.
2. TCR Gene Therapy
Phase I clinical trials (investigator-initiated trials) for the MAGE-A4 antigen-specific T cell receptor (TCR) gene therapy began in March 2014. This therapy targets esophageal cancer using next-generation retroviral vectors developed jointly between Takara Bio and Mie University. These clinical trials are the first attempt in Japan at a genetic immunotherapy for cancer. Takara Bio is also preparing to start up a new projectinvolving NY-ESO-1 antigen-specific TCR gene therapy with the aim of commencing Phase I clinical trials in fiscal 2015.
TCR gene therapy involves taking the patient's lymphocytes and transducing them with the TCR gene, which is capable of recognizing cancer antigens. When re-infused into the patient, the gene-transduced lymphocytes specifically recognize, attack, and eliminate cancer cells. TCR gene therapy is so promising that clinical trials targeting malignant melanoma and other cancers using Takara Bio's RetroNectin® method are already being conducted at the National Cancer Institute in the United States.
3. MazF Gene Therapy
Takara Bio, in a joint effort with both the University of Pennsylvania and Drexel University College of Medicine, commenced an endoribonuclease MazF-based gene therapy Phase I clinical trial in the United States for patients that have been infected with the human immunodeficiency virus (HIV, otherwise known as the AIDS virus). This clinical trial is scheduled for completion in fiscal 2016.
In the mechanism of AIDS, replication of the virus in HIV-infected immune cells causes deficiencies in the entire immune system. However, MazF-modified T-cells (a type of immune cells) are expected to remain functional even if infected by HIV, by preventing replication of the virus. MazF genes are transduced into patient-derived T-cells ex vivo using retroviral vectors that express MazF conditionally upon HIV infection. The MazF-modified T-cells that are infused back into the patients will cleave the RNA strand of HIV and thereby block the replication of the virus when it infects the transduced T-cells. As a result, this method has the potential to become a gene therapy treatment for AIDS.