On December 12, UCLA announced that two prominent UCLA stem cell researchers have received awards from the California Institute of Regenerative Medicine (CIRM), the state stem cell agency. The awards will fund two clinical trials scheduled to begin in 2014: (1) the Binational Phase I clinical trial to test a targeted anti-cancer drug has been approved to enroll patients in US and Canada; and (2) the first in-human testing of stem cell gene therapy for sickle cell disease that allows patients to be their own bone marrow donors. The announcement of the new awards was made at the meeting of the CIRM Independent Citizen’s Oversight Committee (ICOC) at the Luxe Hotel in Los Angeles
The recipients of the awards, the Disease Team Therapy Development III awards, were Dr. Dennis Slamon, Dr. Zev Wainberg, and Dr. Donald Kohn. Drs. Slamon and Winberg’s phase I clinical trial will test a new drug that targets cancer stem cells and has been approved to begin enrolling patients in the US and Canada. Dr. Donald Kohn will conduct the first-in-human trial on stem cell gene therapy for sickle cell disease. At the awards ceremony, Dr. Owen Witte, Director of the UCLA Broad Stem Cell Research Center, noted, “The CIRM support demonstrates that our multidisciplinary Center is at the forefront of translating basic scientific research to new drug and cellular therapies that will revolutionize medicine.”
The award to Dr. Slamon, Dr. Zev Wainberg, and their US-Canadian collaborative team will support the first human clinical trial scheduled to open in early 2014. The trial is based on Dr. Slamon’s previous project to develop a drug that targets tumor initiating cells with Dr. Wainberg, assistant professor of hematology/oncology and Dr. Tak Mak, director, Campbell Family Institute of the University Health Network in Toronto, Canada. Previous research by Dr. Slamon led to the development of Herceptin, the first FDA-approved targeted therapy for breast cancer. He is the director of clinical and translational research at the UCLA Jonsson Comprehensive Cancer Center, and professor, chief and executive vice chair for research in the division of hematology/oncology.
UCLA notes that Drs. Slamon and Wainberg’s trial has received investigational new drug approval from the Food and Drug Administration (FDA) and Health Canada, the Canadian government’s therapeutic regulatory agency; thus, this trial is an international effort to bring leading-edge stem cell science to patients. We are delighted to receive this CIRM grant that will drive our translational research from the laboratory to the clinic,” noted Dr. Slamon. He added, “[It will] allow us to test our targeted drug in a phase I clinical trial.” The trial is based on the evidence, which has accumulated over the last decade for what has become known as the cancer stem cell hypothesis. According to this theory, cancer stem cells are the main drivers of tumor growth and are also resistant to standard cancer treatments. One basis of this theory is that cancer stem cells inhabit a “niche” that prevents cancer drugs from reaching them; another is that tumors can become resistant to therapy by a process called cell fate decision; with this process, some tumor cells are killed by therapy and others become cancer stem cells. These cancer stem cells are believed to be capable of self-regeneration and repopulation of tumor cells, resulting in the recurrence of cancer.
The target of the new drug is an enzyme in cancer stem cells and tumor cells known as Polo-like kinase 4; this target was selected because blocking it impacts cancer stem cell renewal and tumor cell growth; thus, halting tumor growth. Dr. Wainberg explained that this potential anti-cancer drug is now ready to be tested in humans for the first time. He said, “Our goal is to test this novel agent in patients in order to establish safety and then to proceed quickly to rapid clinical development. We are excited to continue this academic collaboration with our Canadian colleagues to test this drug in humans for the first time.” Drs. Slamon, Wainberg, Mak and colleagues will also look for biological indications, called biomarkers, which, scientists can use to tell if and how the drug is working.
Dr. Kohn is a professor of pediatrics and microbiology, immunology and molecular genetics in the life sciences. His team has successfully established the foundation for using hematopoietic (blood-producing) stem cells (HSC) from the bone marrow of patients with sickle cell disease to treat the condition. Dr. Kohn’s gene therapy approach, which uses HSC from the patient’s own blood, is an innovative alternative to current sickle cell disease treatments because it creates a self-renewing normal blood cell by inserting a gene that has anti-sickling properties into HSC. Another plus for the new therapy is that it does not rely on the identification of a matched donor; thus, it avoids the risk of rejection of donor cells. The anti-sickling HSC will be transplanted back into the patient’s bone marrow; there it will produce many new red blood cells that do not have the sickling defect.
Dr. Kohn plans to begin patient enrollment in the clinical trial within the first three months after receiving the CIRM grant. The first patient will be enrolled and observed for safety for six months. The second patient will then be enrolled and observed for safety for three months. If these patients experience no problems, the study will continue with two more patients and another evaluation until six total subjects have been enrolled.
Sickle cell disease affects more than 90,000 patients in the US; the disease primarily affects people of Sub-Saharan African descent. It is caused by an inherited mutated gene that makes red blood cells change from their normal shape, which is round and flexible, into a rigid sickle-shaped cell. Normal red blood cells are able to pass easily through the capillaries; thus, carrying oxygen to organs such as the lungs, liver, and kidneys. However, because of their rigid structure, sickled blood cells get lodged in the capillaries and deprive the organs of oxygen, which causes organ dysfunction and failure.