Research Study Overview
The Thales Research Study is a clinical research trial for people living with beta thalassemia who need regular blood transfusions. The research study will test ST-400, a type of investigational cell therapy involving genome editing.
Listed below are some questions and answers about the research study. If you have general questions about clinical research, please visit the clinical research FAQ tab.
How do I qualify for this research study?
You may qualify for the Thales Research Study if you:
- Are 18 to 40 years old
- Have a diagnosis of beta thalassemia
- Receive regular blood transfusions
- Are in good general health
ST-400 is an investigational treatment made from a person’s own blood stem cells. Your blood stem cells give rise to all the blood cells in your body, including red blood cells. They contain the genetic code to produce hemoglobin, the protein in red blood cells that carries oxygen throughout the body. A portion of the genetic code determines which type of hemoglobin is produced by the body: adult or fetal (baby) hemoglobin. The body typically makes fetal hemoglobin during fetal development and until about six months after birth, when a gene called BCL11A stops its production. In people who do not have beta thalassemia, red blood cells then produce adult hemoglobin to carry oxygen. In people who have beta thalassemia and are not able to make adult hemoglobin, the loss of fetal hemoglobin leads to severe anemia and the need for transfusions.
Scientists at Sangamo have found a way to block BCL11A in such a way that may result in increased fetal hemoglobin production. Since fetal hemoglobin works similar to adult hemoglobin in the body, ST-400 could provide an alternative method to maintain a therapeutic level of oxygen-carrying hemoglobin, which may help reduce or eliminate the need for regular transfusions.
Treatment using a person's own blood stem cells is called "autologous" transplant. Since the cells are their own, autologous transplant avoids some of the risks seen in current transplant treatments, such as rejection and graft-versus-host disease. Currently, allogeneic transplantation is the only known cure for beta thalassemia.
To make ST-400, blood stem cells that are collected from each participant during the study will be genetically edited outside the body to block the BCL11A gene. This modification changes the genetic code in the blood stem cells and may cause increased production of fetal hemoglobin in the red blood cells that they produce. Chemotherapy will then be given to the participant to make room for the new blood stem cells to live in the bone marrow. Following the chemotherapy treatment, the genetically edited blood stem cells (ST-400) are infused back into the participant.
People with severe beta thalassemia do not produce enough functional adult hemoglobin in their red blood cells. Adult hemoglobin contains both two beta globin chains and two alpha globin chains. Together, these four globin chains are responsible for the transportation of oxygen throughout the body. In beta thalassemia patients, beta globin chain production is abnormally low-to-absent, which leads to the destruction of red blood cells.
Fetal hemoglobin is the major hemoglobin that is present in the body until birth. In the months following birth, fetal hemoglobin normally is gradually replaced by adult hemoglobin. Fetal hemoglobin has similar characteristics to adult hemoglobin, but is made up of two gamma globin chains and two alpha globin chains. Like adult hemoglobin, fetal hemoglobin is able to carry oxygen throughout the body.
Fetal hemoglobin has been the focus of much research aiming to cure people living with dysfunctional forms of beta globin. Doctors have found that natural or drug-induced boosts in fetal hemoglobin are associated with better red blood cell survival and milder forms of disease in people with beta thalassemia. The goal of the Thales research study, therefore, is to modify a gene in the blood stem cells to permanently increase fetal hemoglobin production. This type of treatment is also known as “genome editing”.
Doctors are studying ST-400 to see if it is safe and tolerable, and to learn whether it may be effective at increasing fetal hemoglobin and reducing the symptoms of beta thalassemia.
Click on the “About genome editing” page to learn more about ST-400 and genome editing.
Yes. The research study will enroll a total of 6 participants, all of whom will receive ST-400. The dose given to each participant depends on the body weight of the participant. As a safety precaution, a portion of the participant’s own unmodified blood stem cells will be kept and stored in case a rescue treatment is needed.
In the unforeseen situation that a participant's body does not accept his/her edited blood stem cells, a rescue treatment can be given. This involves infusing the participant’s own, unedited blood stem cells, back to the participant.
No. All research study medication and research study-related care will be at no cost to the participant. Transportation assistance, including reimbursement for travel expenses, may also be available.
After receiving the ST-400 infusion, the study staff will follow the participant’s health for 3 years. Participants will make regular study appointments with the research study staff, and the staff will work with participants to find convenient times for these visits. At these visits, the research study staff will check the participant’s health to study the effects of the investigational therapy.
If for some reason a participant will need to leave the research study, they may do so at any time.
You will need to stop iron chelators from before you receive ST-400 until your doctor tells you it is alright to restart them.
Unless your doctor thinks they are needed, you may not receive the following medications while you are participating in the research study:
- Erythropoietin or similar medications used to boost red blood cell production
- Systemic chemotherapy drugs
- Prolonged use of medications that suppress the immune system
- Experimental medications
- Any medication expected to alter hemoglobin F levels
These medications will need to be stopped at least 30 days prior to the screening visit.
To learn more about the research study opportunity, please contact firstname.lastname@example.org.