A new development in sickle cell treatment continues to expand options for the disease.
The Food and Drug Administration recently expanded the indication for the CRISPR/Cas9 gene-editing therapy Casgevy. It now includes children as young as 2 years old with severe sickle cell disease or transfusion-dependent beta thalassemia. The FDA previously approved the therapy for adolescents 12 and older with these conditions.
This marks the first gene therapy approved for toddlers in the United States. The expanded approval is expected to increase access to the gene-editing therapy.
The federal agency calls the new development a critical step toward increasing access to life-saving therapy. The broader eligibility allows more children to receive treatment during a critical stage of disease progression when irreversible organ damage may still be preventable.
“Pediatric patients as young as 2 years of age can now access a critical additional treatment option to treat these debilitating, life-threatening diseases,” said Karim Mikhail, the acting director of the FDA’s Center for Biologics Evaluation and Research. “Grounded in the scientific evidence that earlier treatment reduces the risk of lasting end-organ damage, making this therapy available to younger patients opens a critical window for intervention and gives these children a meaningful chance at a healthier future.”
The approval marks another major advancement for sickle cell treatment within the past three years. Since the FDA granted the first breakthrough approval in 2023, it has approved two gene therapies, Casgevy and Lyfgenia, to treat the disease.
According to Casgevy manufacturer Vertex, the approval will make more than 5,000 additional children with sickle cell disease eligible for treatment.
Pivotal Trials Lay the Foundation For Pediatric Approval In Sickle Cell Disease
Early clinical trial data supported the expanded approval by showing the potential of Casgevy in younger patients. The trial did not enroll children younger than 4 years old. Data from patients ages 5 to 11 supported the FDA’s decision to expand the indication to 2 years olds.
“The FDA based the approval on product characteristics and clinical study data,” the agency wrote in a press release. “Extrapolation to the younger pediatric age population was granted to expand the indication to 2 years of age and older for both conditions.”
Participants experienced at least two severe vaso-occlusive crises each year in the two years before entering the trials. The trial is ongoing and will continue evaluating long-term safety and efficacy for up to 15 years.
The study evaluated a gene-editing approach designed to reactivate fetal hemoglobin, which is a form of hemoglobin that can reduce the effects of sickle cell disease. By increasing fetal hemoglobin production within the body, the therapy aims to reduce vaso-occlusive crises. Those are painful episodes that are characteristic of the disease.
In an initial study of 15 children under the age of 5 with transfusion-dependent beta thalassemia, eight of nine patients achieved transfusion independence for at least 12 consecutive months. The median duration of transfusion independence was 20.1 months.
The trials were led by Dr. Haydar Frangoul, medical director of Pediatric Hematology and Oncology at TriStar Centennial Children’s Hospital. As principal investigator for Casgevy’s pediatric clinical trials, Frangoul helped evaluate the therapy in children with severe sickle cell disease.
His work helped advance a new treatment option for children with limited alternatives. The expanded approval gives younger patients access to a therapy that could alter the course of their disease.
Clinical Trial Representation For A Disease That Has Affected Black Communities
The Casgevy trial mainly enrolled Black and African American patients. Nearly 91% of participants in the Casgevy clinical trial were Black, representing the community most affected by sickle cell disease in the U.S.
Sickle cell research has historically struggled with recruitment and retention. Up to 57% of sickle cell disease clinical trials terminate early due to low enrollment.
“We’re deeply grateful to the patients, families and investigators who participated in the clinical trials that led to this historic approval, and we are ready to bring CASGEVY to children and their families across the U.S.,” said Vertex CEO Reshma Kewalramani.
The communities most affected by sickle cell disease often face barriers to trial enrollment. Participation can be limited due to medical mistrust linked to historical inequities, disruptions from painful disease complications and limited access to specialty care or research sites. The Sickle Cell Disease Association of America, a national patient advocacy, expressed excitement for the expanded approval in supporting at need communities.
“The Medical Research and Advisory Committee of the Sickle Cell Disease Association of America, Inc., is excited about the Food and Drug Administration’s approval of Casgev” the advocacy group wrote in a release. ” This approval by the FDA brings the sickle cell community much closer to realizing the goal of reducing the burden of living with SCD.
Despite Advancements Access Remains A Challenge For Sickle Cell Patients
For families, earlier intervention could mean reducing not only medical complications but also the ongoing burden of managing a lifelong condition within the healthcare system.
About one in 365 Black births are affected by sickle cell disease, according to the Centers for Disease Control and Prevention. Americans with sickle cell face a shortened life expectancy, often living 20 years shorter than the national average. In addition to the physical and mental burden, many patients report stigma and treatment barriers.
Studies have found that many people with sickle cell disease face delays or denials in receiving pain treatment during emergency room visits. Some patients report that their symptoms are dismissed or stereotyped as “drug seeking.”
These experiences contribute to inadequate pain management and erode trust between patients and clinicians. They also shape how patients engage with the healthcare system and clinical trials.
Patients who experience discrimination are more likely to report lower trust in the healthcare system. They were also more likely to be non-adherent to medical recommendations.
In some cases, previously stigmatized patients avoided disclosing their condition to healthcare providers because of concerns about stigma or previous negative experiences.
Pediatric Approval Opens New Treatment Opportunities
The expanded pediatric indication creates an opportunity for earlier intervention, before irreversible organ damage occurs from progressive sickle cell disease.
Some families hope earlier treatment will reduce the lifelong burden of frequent healthcare visits, painful crises, and the challenges of navigating care for a chronic condition.
In a press release, the Sickle Cell Disease Association of America recognized the potential of cell and gene therapies to cure the disease. But the patient advocacy group emphasized the need for patients and families to understand the risks and challenges involved.
The organization highlighted concerns around the complexity of cell collection and manufacturing, treatment timelines, financial and caregiving burdens, and unknown long-term effects. It encouraged healthcare providers and manufacturers to ensure patients and families have the information needed to make informed decisions.
“Although these challenges should not prevent patients from pursuing the therapy, we encourage hematologists and gene therapy manufacturers to be forthcoming in informing patients and their families of these issues,” the organization shared in a statement.
A one-time treatment of Casgevy has a list price of $2.2 million. The treatment is covered by select commercial plans and Medicare Part B, if determined to be medically necessary and administered at a qualified, in-network treatment center.
