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Cancer was once the biggest killer threatening human life and health. With the progress of life science and technology and the improvement of medical level, cancer treatment has made great breakthroughs. Conquering cancer no longer seems out of reach.
Besides surgery, radiation, and chemotherapy, immunotherapy has become the fourth pillar of cancer therapy. It includes some new therapies: monoclonal antibody, double-antibody, ADC, PD-1/L1, the cell therapies,like CAR-T, vaccines and the oncolytic virus.
Like magic, oncolytic viruses use viruses to cure tumors
Oncolytic virus is literally a virus that can dissolve tumors. Using viruses to fight tumors and treat cancer is one of the most popular immunotherapy methods.
Oncolytic virus is a kind of natural or genetically engineered virus that can selectively replicate in tumor tissue, and then infect and kill tumor cells or cause tumor cell lysis, but has no killing effect on normal tissue. Because of this machinsm, oncolytic virus therapies are receiving increasing attention from cancer patients and the industry market.
In 2004, the first oncolytic virus product Rigvir(Echo-7 virus) was approved in Latvia, and the next year, the first oncolytic virus drug Ankorian (recombinant human adenovirus type 5) was also approved in China. In 2015, the US FDA approved the first oncolytic virus drug T-VEc (herpes simplex virus) for the market, and the development of oncolytic virus therapy is becoming mature In June 2021, Daiichi Sankyo Announced that its oncolytic virus product Delytact(TeserpatureV /G47) was approved in Japan by the Ministry of Health, Labor and Welfare (MHLW) for the treatment of malignant glioma which is the fourth such product to be approved worldwide.
As more and more large pharmaceutical companies at home and abroad set up business in oncolytic virus sector, oncolytic bacteria entered the tumor immunotherapy market, opening up a new subpision of the tumor therapy field.
New cancer immunotherapy: the oncolytic bacterium YB1 joins the race
In fact, using bacteria to treat tumors has been around for hundreds of years. In the late 19th century, American surgeon William Corley found the inspiration of using bacteria to treat cancer from a self-healing cancer patient. After decades of exploration and practice, he pioneered the method of treating cancer with bacteria. William Colley is regarded as the father of tumor immunotherapy.
Although the idea of using bacteria to treat cancer was first developed over a century ago and research on bacterial therapies has never stopped, few drugs have entered clinical trials and been marketed. The only related drug currently on the market is the therapeutic BCG vaccine which is used for postoperative perfusion of bladder cancer.
The birth of the oncolytic bacterium YB1 heralds a new approach in the field of tumor immunotherapy, using bacteria to treat tumors.
In 2011, the R&D team of HKND YB1 PHARMACEUTUCAL LIMITED. accomplish the highly efficient programming technology of Salmonella Lambda-RED for the first time and established the basis of the synthetic biology transformation of Salmonella. After more than a decade of development, the R&D team created YB1 which is a tumor-lytic Salmonella Typhimurium.HKND YB1 PHARMACEUTUCAL LIMITED. is the first biomedical company which successfully develop oncolytic bacteria carriers in the world. It focuses on the research and development of innovative drugs in the tumor targeted therapy area and owns the world's leading synthetic biology-based oncolytic bacteria technology platform. Committed to providing revolutionary cancer immunotherapy solutions to the world.
Studies have shown that the oncolytic bacterium YB1, as a carrier, can efficiently deliver and carry drugs including antibodies, mRNA, protein drugs, oncolytic viruses, etc. to precisely target the hypoxic region in the tumor center and replicate and amplify in large quantities inside the tumor, thus increasing the concentration of YB1 in solid tumors. YB1 has great clinical application potential that could release a variety of therapeutic drugs inside the tumor to inhibit tumor growth and dissolve tumor as well as eliminate tumor metastasis.After arriving at the tumor inside, YB1 can release a variety of therapeutic "warhead" drugs which carried by YB1 to inhibit tumor growth and dissolute tumor,while eliminate tumor metastasis. This treatment process has great clinical application potential in oncological field.
The differences between oncolytic bacteria and oncolytic virus
In fact, both oncolytic bacteria and oncolytic viruses are very emerging in the field of tumor immunotherapy and both belong to the category of oncolytic carriers.
From the point of their respective characteristics, oncolytic viruses can replicate in cancer cells and release cytokines or antibodies drugs which carried by viruses. Compared with oncolytic bacteria, oncolytic viruses also has many shortcomings. Firstly, viruses need to find a host cell and invade into the cell to replicate. Most oncolytic viruses are engineered to invade only cancer cells for the purpose of safety to patients. However, only 10%-20% of solid tumors are tumor cells and most of the others are support cells. Oncolytic viruses could not act on these support cells which manily are immune cells. So there is no way to guarantee the invasion efficiency of oncolytic viruses.
Secondly, most oncolytic viruses are injecting into tumor to cure cancer. By this way, the limitations of the application are greatly increase. Thirdly, the genome of viruses is relatively small, so the capacity as a carrier is limited. Fourthly, if viruses is out of control, the risk of infection will highly increase.Fifthly, there is a risk that the virus will modificate the human genome.
As the first oncolytic bacterial carrier in the world,YB1 has remarkable characteristics. First of all, YB1 can identify tumor regions according to the difference in oxygen concentration and achieve targeted colonization of tumor regions. Therefore, in addition to intratumoral injection,YB1 can reach the tumor by intravenous IV injection. Second, oncolytic bacteria are independent of host cells and have the ability to self-proliferate. YB1 is sensitive to hypoxic microenvironment and can not only identify tumor regions, but also invade host cells in hypoxic microenvironment. Therefore, in addition to tumor targeting, YB1 also increases the scope of action on tumors to achieve better therapeutic effects.
In addition,YB1 can carry large amounts of the drug due to the large genetic assembly load of oncolytic bacteria. YB1 can be directly combined with antibodies, protein drugs and mRNA vaccines and achieve the coverage of drugs in the whole tumor region, which is also a difficult barrier for oncolytic viruses to overcome. Assumed that YB1 is out of control in the body, by using sensitive antibiotics to stop the treatment or research without damage. At the same time, YB1 has no risk that the virus will modificate the human genome.
Although the development of oncolytic bacteria is not yet mature, the competitive advantage of oncolytic bacteria immunotherapy represented by YB1 can not be ignored. Tumor immunotherapy will usher in a new era, Cancer therapeutics will be a step up.
