• Posted June 12, 2023

More Evidence Gene Therapy Might Cure Sickle Cell Disease

A clinical trial that's attempting to discover a cure for sickle cell disease has found a new gene therapy to be safe and successful in four patients.

Two of the patients were treated at Cleveland Clinic Children's in Ohio, and doctors there are hopeful that their positive results will be borne out in future research.

“New treatments like this are critical for people who have sickle cell disease,” said researcher Dr. Rabi Hanna, director of the pediatric blood and bone marrow transplant program at Cleveland Clinic Children's.

“These initial results provide hope that this new technology will continue to show progress as we work toward creating a possible functional cure for this devastating and life-threatening disease,” Hanna added in a hospital news release.

Sickle cell disease, a genetic blood disorder, is painful and debilitating. About 100,000 Americans have the disease, which is more common in Black people.

Instead of being round, blood cells are shaped like sickles, which limits their ability to carry oxygen. Sickle cells also tend to stick together, blocking small blood vessels. It can cause liver fibrosis, liver failure, stroke, cardiomyopathy (heart muscle disease) and heart failure.

The multicenter Ruby Trial, as it's called, aims to enroll 40 patients with severe sickle cell disease.

This experimental, one-time gene-editing therapy modifies a patient's own blood-forming stem cells. The idea is to correct the mutation responsible for sickle cell disease.

The four patients had their stem cells collected for gene editing, and then had chemotherapy to destroy their remaining bone marrow. The repaired cells were then infused back into their body.

The CRISPR gene-editing technology utilized is called CRISPR/CA12. It is a highly precise tool to modify blood stem cell genomes so the body can produce robust, healthy blood cells.

The study found new white blood cells in all four patients at about four weeks with no severe adverse effects.

Patients also achieved a normal level of hemoglobin, the researchers said. This is the most important component of red blood cells that carry oxygen throughout the body.

Also important, the patients did not have pain attacks for many months following therapy.

Medications can help with symptoms, but not cure sickle cell disease. The average lifespan of a sickle cell patient is in the mid-40s.

The trial results were presented Friday at a meeting of the European Hematology Association in Frankfurt, Germany. Findings presented at medical meetings should be considered preliminary until published in a peer-reviewed journal.

More information

The U.S. Centers for Disease Control and Prevention has more on sickle cell disease.

SOURCE: Cleveland Clinic, news release, June 9, 2023