TOKYO -- Stem cells have enormous promise in regenerative medicine, with the potential to treat a range of injuries and diseases, from Parkinson's and cancer to infertility and baldness. The main roadblock, however, has been ethical concerns regarding the use of human embryonic tissue. But now, new technologies are starting to come onto the market that sidestep those issues, opening the door to innovative therapies, as well as identify new drugs by screening using stem cells.
International Stem Cell Corp. (ISCO) will soon start a phase I clinical trial in Australia using the company's ISC-hpNSC, human parthenogenetic stem cell-derived neural stem cells, for the treatment of Parkinson's disease, the second most common neurodegenerative disease.
California-based ISCO pioneered the development of a new class of stem cells, created by chemically stimulating unfertilized human oocytes (eggs), thereby creating a host of opportunities to treat a broad range of different diseases. The unfertilized eggs do not have the potential to become embryos, and no viable embryo is created or destroyed.
The Nikkei Asian Review recently spoke with Dr. Russell Kern, chief scientific officer of the company, about the upcoming clinical trial and new developments in regenerative medicine.
Q: Can you elaborate on the clinical trial about to start in Australia?
A: Parkinson's disease is a degenerative disorder and a serious disease that affects millions of people all over the world. The disease occurs when dopaminergic neurons die in an area of the brain that controls movement. Dopaminergic neurons produce an important brain chemical messenger or neurotransmitter known as dopamine. When the dopaminergic neurons die, there is a shortage of dopamine that causes the movement problems of people with Parkinson's. The clinical trial we are about to start in Australia is based on extensive preclinical studies in rodents and nonhuman primates. After transplantation of ISCO's stem cells, our studies showed a significant increase in brain dopamine levels as well as neurotrophic support and cell replacement of dopaminergic neurons. ISCO's preclinical studies demonstrated improvement in Parkinson's disease symptoms, while being safe, well tolerated and not causing severe adverse effects.
The first-of-its-kind clinical trial will be conducted at the prestigious Royal Melbourne Hospital in Australia and will look at efficacy and safety as well as improvement in the quality of Parkinson's disease patients' lives through better control of movement as well as an improvement in their overall psychological condition.
Q: What are the characteristics of parthenogenetic stem cells?
A: They are demonstrating excellent characteristics when compared with other classes of stem cells. For example, parthenogenetic stem cells simplify therapies in regenerative medicine by potentially circumventing problems of immune rejection by limiting mismatching between stem cell-based therapeutic products and individual patients.
In recognition of the potential of our platform, in 2015 the Japan Patent Office and the European Patent Office granted ISCO protection on our stem cell lines. The patents cover the new method of creating stem cells that combine many of the benefits of embryonic stem cells with induced pluripotent stem (iPS) cells and can be used to generate virtually unlimited quantities of human cells. Currently, at the company, we are using this technology to develop treatments for a number of indications where cell therapy has been demonstrated to be effective but where there is an insufficient supply of safe, functional cells.
Being able to produce parthenogenetic stem cells in large quantities and in a way that greatly simplifies the chances of immune matching gives us a clear advantage over other stem cell technologies, like embryonic stem cells for obvious reasons. One of ISCO's stem cell lines matches approximately 70 million people, as it makes it incredibly simple to immune match its stem cells. Based on our stem cell line safety profile and quality of manufacturing, the U.S. Food and Drug Administration cleared ISCO's parthenogenetic stem cell line for use in investigational clinical studies. This stem cell line will be the base of the clinical trial in Australia.
ISCO's neural stem cells are produced in large scale and with economic efficiency at the company's current Good Manufacturing Practices facility (cGMP) in San Diego, California. cGMP is the main regulatory standard for ensuring pharmaceutical quality for human pharmaceuticals enforced by the FDA.
Q: How do you see stem cell research in other countries? For instance, Japan has been very active in this field.
A: ISCO has been producing its stem cell lines for its stem cell bank and for corporate and academic customers worldwide, including Japan.
Japan is positioning itself to play a leadership role in regenerative medicine. Since iPS cells were discovered by the Japanese scientist Shinya Yamanaka of Kyoto University, the country has been on a quest to become a leader in the field. Dr. Yamanaka was awarded the Nobel Prize in Physiology or Medicine in 2012.
To advance research and the development of treatments based on stem cells, the Japanese government passed legal reforms to streamline the regulatory process in the development of therapies. The new regulatory environment makes Japan the most liberalized market for stem cell therapies.
Taking its cue from the government, the corporate sector has been active in making acquisitions throughout the world to gain knowledge, scientific talent and expertise.
In 2015, Astellas Pharma acquired Ocata Therapeutics to play "a key role in Astellas' R&D in ophthalmology and cell therapy." The same year, seeking entry into stem cell-based research of drug discovery support services, Fujifilm Holdings acquired U.S.-based Cellular Dynamics International. Fujifilm hopes the acquisition will help accelerate product development in regenerative medicine and expand commercial opportunities.
Globally, there are a number of stem cell therapies in development promising to treat conditions that traditional medicine cannot. Additional good news for patients is that cell therapies are widely discussed and interest is growing in academic and industry circles.
Interviewed by Nikkei senior deputy editor Seiichiro Mishina