The U.S. Food and Drug Administration (FDA) approved two breakthrough genes** for sickle cell disease last Friday, including the first to use gene editing technology**.
Cas9 (or CAS:Guide RNA combined shearing nucleic acid protein system) was developed by Vertex Pharmaceuticals in Boston and CRISPR Therapeutics in Switzerland. Cas9 is currently the first drug in the United States to use CRISPR gene editing technology to ** genetic diseases.
Experts say this one-time** can permanently alter the DNA in a patient's blood cells, freeing them from the painful symptoms of sickle cell disease, but this relief is likely to be very expensive.
Another approved modality is Lyfgenia, which uses a common virus to genetically modify hematopoietic stem cells into a patient's bone marrow. This ** was developed by Bluebird Biologics of Sommerville, Massachusetts.
"Sickle cell disease is a rare, debilitating, life-threatening blood disorder with a huge unmet need, and we are very excited to advance this area, especially for those whose lives have been severely disrupted by this disease, and our approval today of two cell-based genes brings new hope to this disease," said Dr. Nicole Willen, director of the FDA's Product Office, at the FDA's press release.
Genomics is expected to provide a more targeted and effective approach, especially for patients with rare diseases, where the current options are very limited," Ferdon added.
In both cases, stem cells are taken from the patient's blood for processing.
Using CAS9, CRISPR gene editing technology can knock out genes associated with crescent-shaped blood cells that cause stunted growth. At the same time, medicine works by eliminating imperfect hematopoietic cells in patients and allowing patients to regain their own engineered stem cells.
The same thing happened to Lysenia, except that the virus was used to deliver the genetic payload so that the blood cells started producing healthy hemoglobin.
The genetically modified stem cells are then infused back into the patient, given only once as a single infusion.
In a press release from the FDA, Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, noted, "These approvals represent a major medical advance in innovative cell-based genes** that target diseases that can have devastating consequences and help improve public health." ”
Today's actions come after a rigorous evaluation of the scientific and clinical data needed to support approval, reflecting the FDA's commitment to providing a safe and effective** approach for those diseases that have a significant impact on human health," Marks added.
The evidence supporting Casgevy's approval concerns 44 patients who underwent the gene editing process**. Of the 31 patients who were followed long enough for evaluation, 29 were completely free of severe pain and organ damage, which can occur when sickle cell disease worsens.
Any approach that can help alleviate the pain and multiple health complications that come with this condition is amazing," Dr. Alison King, a professor at Washington University School of Medicine in St. Louis, recently told The Associated Press. "It's a very painful disease. Some people say it's like being stabbed all over your body. ”
In addition, none of the patients experienced graft failure or graft rejection.
Vitesse said it plans to follow clinical trial patients for up to 15 years.
According to the Associated Press, Victoria Gray, who received the gene, recently shared her experience with researchers at a scientific conference, where she said she felt "reborn" when she received it. Gray has suffered from pain since childhood.
Now, she actively engages with children and works full-time.
My kids are no longer afraid of losing their mom to sickle cell disease," she said.
The approval of Lyfgenia was supported by a 24-month study involving 32 patients who underwent **. Of these, 28 patients did not develop sickle cell events after transplantation.
Sickle cell disease affects the proteins in red blood cells that carry oxygen. Red blood cells may become meniscus due to genetic mutations, which can block blood flow, causing pain, organ damage, and stroke. The disease affects millions of people worldwide.
This phenomenon is more common in areas where malaria is prevalent, such as Africa and India. Carrying this trait may help prevent severe malaria.
Criteria include medications and blood transfusions. Bone marrow transplantation from a disease-free donor with the same type is the only method.