The first patient to receive gene therapy for sickle cell disease since its approval is finally home.
The New York Times reported that staff members were overjoyed as 12-year-old Kendric Cromer left Children’s National Hospital in Washington, DC, in a wheelchair on Oct. 16, 2024.
Kendric is one of approximately 20,000 people with the most severe form of sickle cell disease. This condition results from a mutation in the hemoglobin genes, causing red blood cells to take on a crescent shape. These misshaped cells can block blood vessels, leading to severe pain, stroke, organ damage, and reduced life expectancy.
“I thought I would have sickle cell for the rest of my life,” Kendric said, according to The Times. Throughout his childhood, the disease had prevented him from enjoying playing basketball or riding a bike. Such activities would trigger pain and require frequent trips to the hospital.
According to the Centers for Disease Control and Prevention, about 100,000 people in the U.S. have sickle cell disease, the most common inherited blood disorder in the country. Over 90% of those affected are non-Hispanic Black or African American.
In December 2023, the Food and Drug Administration approved a $3.1 million gene therapy for sickle cell developed by Bluebird Bio and a $2.2 million treatment from Vertex Pharmaceuticals, offering hope to patients like Kendric.
His treatment began on May 1, 2024, with doctors extracting stem cells from his bone marrow and sending them to a New Jersey lab. There, technicians introduced new, healthy hemoglobin genes into the cells. A few months later, Bluebird shipped Kendric’s modified cells back.
Children’s National Hospital admitted Kendric for the final phase of his treatment on Sept. 3. On Sept. 5, he began intense chemotherapy to clear his bone marrow and prepare for the infusion of the treated cells, which took place on Sept. 11.
Kendric’s doctors informed his parents that he would need to stay in the hospital for about a month, and soon after, the side effects of the chemotherapy began.
First, Kendric developed mucositis, a severe inflammation that caused painful sores in his mouth and intestinal tract. His tongue reportedly swelled so much that he could barely talk or eat, according to his mother, Deborah Cromer. Additionally, every joint in his body ached, and he experienced a rare side effect that left him looking as if “he’d put his hands on a hot stove,” she said.
His skin darkened and peeled, and his hair fell out. However, Kendric eventually began to feel better, and after 44 days in the hospital, he headed home. His treatment will continue with visits to the hospital every two to four weeks for bloodletting — a process that removes blood to treat or prevent illness — since the transfusions left him with excess iron in his bloodstream. The chemotherapy also weakened his immune system, so he will need to be re-immunized with childhood vaccines and avoid crowds for several months to recover.
“I haven’t felt all the amazingness yet,” Kendric said, according to The Times. “But I am slowly starting to feel better.”
