Bone marrow stem cell transplant

The race to cure sickle cell disease

/ Kevin McCormack / Leave a comment

September is National Sickle Cell Awareness Month, a time to refocus our efforts to find new treatments, even a cure, for people with sickle cell disease. Until we get those, CIRM remains committed to doing everything we can to reduce the stigma and bias that surrounds it.

Sickle cell disease (SCD) is a rare, inherited blood disorder in which normally smooth and round red blood cells may become sickle-shaped and harden. These blood cells can clump together and clog up arteries, causing severe and unpredictable bouts of pain, organ damage, vision loss and blindness, strokes and premature death.

There is a cure, a bone marrow transplant from someone who is both a perfect match and doesn’t carry the SCD trait. However, few patients are able to find that perfect match and even if they do the procedure carries risks.

That’s why the California Institute for Regenerative Medicine (CIRM) has invested almost $60 million in 14 projects, including five clinical trials targeting the disease. It’s also why we are partnering with the National Heart, Lung and Blood Institute (NHLBI) in their Cure Sickle Cell Initiative (CureSCi).

As part of the events around National Sickle Cell Awareness Month the NHLBI is launching the Gene Therapy to Reduce All Sickle Pain (GRASP) Trial and hosting a special Journeys in Mental Health Webinar on September 27th. 

The GRASP Trial is a Phase 2 trial that will take place at various locations throughout the country.  It’s a collaboration between the NHLBI and CIRM. Researchers are testing whether a gene therapy approach can improve or eliminate sickle cell pain episodes.  

Shortly after being born, babies stop producing blood containing oxygen-rich fetal hemoglobin and instead produce blood with the adult hemoglobin protein. For children with sickle cell disease, the transition from the fetal to the adult form of hemoglobin marks the onset of anemia and the painful symptoms of the disorder.

Scientists previously discovered that the BCL11A gene helps to control fetal hemoglobin and that decreasing the expression of this gene can increase the amount of fetal hemoglobin while at the same time reducing the amount of sickle hemoglobin in blood.  This could result in boosting the production of normal shaped red blood cells with a goal of curing or reducing the severity of sickle cell disease.   

The approach used in this trial is similar to a bone marrow transplant, but instead of using donor stem cells, this uses the patient’s own blood stem cells with new genetic information that instructs red blood cells to silence the expression of the BCL11A gene. This approach is still being studied to make sure that it is safe and effective, but it potentially has the advantage of eliminating some of the risks of other therapies. 

In this trial, patients will have to spend some time in an inpatient unit as they undergo chemotherapy to kill some bone marrow blood stem cells and create room for the new, gene-modified cells to take root.

The trial is based on a successful pilot/phase 1 study which showed it to be both safe and effective in the initial 10 patients enrolled in the trial.

For more information about the trial, including inclusion/exclusion criteria and trial locations, please visit the CureSCi GRASP trial page.

Nancy Rene, a sickle cell disease patient advocate, says while clinical trials like this are obviously important, there’s another aspect of the treatment of people with the disease that is still too often overlooked.

“As much as I applaud CIRM for the work they are doing to find a therapy or cure for Sickle Cell, I am often dismayed by the huge gulf between research protocols and general medical practice. For every story I hear about promising research, there is often another sad tale about a sickle cell patient receiving inadequate care. This shouldn’t be an either/or proposition. Let’s continue to support ground-breaking research while we expand education and training for medical professionals in evidenced based treatment. I look forward to the day when sickle cell patients receive the kind of treatment they need to lead healthy, pain-free lives.”

Stem Cell Agency Board Approves Funding for Rare Immune Disorder

/ Kevin McCormack / Leave a comment

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Taylor Lookofsky (center), a person with IPEX syndrome, with his father Brian and Dr. Rosa Bacchetta

IPEX syndrome is a rare condition where the body can’t control or restrain an immune response, so the person’s immune cells attack their own healthy tissue. The syndrome mostly affects boys, is diagnosed in the first year of life and is often fatal. Today the governing Board of the California Institute for Regenerative Medicine (CIRM) invested almost $12 million in a therapy being tested in a clinical trial to help these patients.

Children born with IPEX syndrome have abnormalities in the FOXP3 gene. This gene controls the production of a type of immune cell called a T Regulatory or Treg cell. Without a normal FOXP3 +Treg cells other immune cells attack the body leading to the development of IPEX syndrome, Type 1 diabetes, severe eczema, damage to the small intestines and kidneys and failure to thrive.

Current treatments involve the use of steroids to suppress the immune system – which helps ease symptoms but doesn’t slow down the progression of the disease – or a bone marrow stem cell transplant.  However, a transplant requires a healthy, closely matched donor to reduce the risk of a potentially fatal transplant complication called graft vs host disease, in which the donated immune cells attack the recipient’s tissues.

Dr. Rosa Bacchetta and her team at Stanford University have developed a therapy using the patient’s own natural CD4 T cells that, in the lab, have been genetically modified to express the FoxP3 gene and converted into Treg cells. Those cells are then re-infused into the patient with a goal of determining if this approach is both safe and beneficial. Because the cells come from the patients there will be fewer concerns about the need for immunosuppressive treatment to stop the body rejecting the cells. It will also help avoid the problems of finding a healthy donor and graft vs host disease.

Dr. Bacchetta has received approval from the Food and Drug Administration (FDA) to test this approach in a Phase 1 clinical trial for patients suffering with IPEX syndrome.

“Children with IPEX syndrome clearly represent a group of patients with an unmet medical need, and this therapy could make a huge difference in their lives,” says Dr. Maria T. Millan, the President and CEO of CIRM. “Success of this treatment in this rare disease presents far-reaching potential to develop treatments for a larger number of patients with a broad array of immune disorders resulting from dysfunctional regulatory T cells.”

In addition to a strong scientific recommendation to fund the project the review team also praised it for the applicants’ commitment to the principles of Diversity, Equity and Inclusion in their proposal. The project proposes a wide catchment area, with a strong focus on enrolling people who are low-income, uninsured or members of traditionally overlooked racial and ethnic minority communities.