There is good news that the sickle cell anemia, which is a slow killer that induces immense pain, is curable with gene therapy. This was disclosed by doctors at the Necker Children's Hospital in Paris, where a boy afflicted with sickle cell disease attained complete cure after genetic engineering therapy treatment on a trial basis.
Globally, 275,000 infants are born carrying sickle cell disease and in the United States, the number reaches to 100,000 mostly among kids of African ancestry. Among the black children in America, one in every 365 infants is suffering from the disease right from birth.
Inherited Blood Disorder
The rare disease is an inherited blood disorder whose hallmark is hemoglobin abnormality in the red blood cells with clotting of blood taking place in the veins and organs.
Another risk faced by patients with sickle cell disease is the shortened life span, which gets reduced by decades compared to the general population, according to Dr. Grace Onimoe of the American Sickle Cell Anemia Association.
The details have been published in The New England Journal of Medicine. The patient received 15 months of treatment since the age of 13 and is now free from medication as his blood cells carry no trace of the disease, according to the doctors.
"Since therapy was applied, he hasn't had any pain, any complications. He is free of any transfusions. He plays sports and goes to school," said Dr. Philippe Leboulch, author of the research and a professor of medicine at the University of Paris.
Serious Gene Disorder
Leboulch explained that sickle cell disease is a common gene disorder where the blood clogging is the fallout of the genetic mutation caused to hemoglobin that distorts the cell's shape.
Dr. Marina Cavazzana, heading the biotherapy department at Necker, added that all biological tests showed that the boy has been cured, though a longer follow-up is still needed.
Cavazzana expressed the hope that other patients carrying the disorder may be able to receive the gene therapy in another five years.
In the treatment, bone marrow of the boy was extracted, stem cells were harvested, and the gene code was altered to make normal hemoglobin. This was followed by a course of chemotherapy to curate the affected stem cells which were later inducted into the patient's bloodstream.
The patient showed visible relief compared to his previous conditions of heavy pain that required frequent blood transfusions and necrosis of the hip — a complication that required hip replacement surgery.
Leboulch and her team are also using similar gene therapy for treating thalassemia, which is another blood disorder marked by hemoglobin shortage and the skewed number of RBC.
Complications In Treatment
At present, bone marrow transplant is the only long-term treatment available. It is a procedure that requires prolonged blood transfusions to mitigate the pain and not all patients are eligible for.
Noting the merit of gene therapy, Dr. Alexis Thompson of the American Society of Hematology noted that the right match for bone marrow donation has been the main hurdle in the current treatment. Most sickle cell disease patients may not have a brother or sister to be donors. Now, gene therapy can address that constraint as the patient himself is the donor.