FDA Approves First Sickle Cell Disease Drug in Nearly 20 Years

The approval greatly expands treatment options for rare inherited blood disorder.

Today, the FDA approved L-glutamine oral powder (Endari) for the treatment of sickle cell disease. The drug is indicated to reduce complications associated with the condition in patients 5 years and older, according to a press release.

"Endari is the first treatment approved for patients with sickle cell disease in almost 20 years," Richard Pazdur, MD, acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research and director of the FDA’s Oncology Center of Excellence, said in the release. "Until now, only 1 other drug was approved for patients living with this serious, debilitating condition."

Sickle cell disease is a disorder in which the red blood cells are abnormally shaped, resulting in restricted blood flow to the vessels. The condition is characterized by severe pain and organ damage due to inadequate blood flow, according to the release.

The National Institutes of Health reports that 100,000 patients in the United States have the condition, occurring most often among African Americans, Latinos, and other minority groups. Patients with sickle cell disease are only expected to live 40 to 60 years, which highlights the need for new innovation in the disease space.

The safety and efficacy of L-glutamine was explored in a clinical trial of patients aged 5 to 58 years with sickle cell disease. All patients included had at least 2 painful crises within the 12 months prior to enrollment. Patients were randomized to receive L-glutamine or placebo for 48 weeks.

Patients treated with L-glutamine experienced less hospital visits for pain with a parenterally administered narcotic or ketorolac—– known as sickle cell crises­­––compared with placebo patients, according to the FDA.

Patients receiving L-glutamine were also observed to have fewer hospitalizations for sickle cell pain and fewer hospital days compared with placebo patients. L-glutamine treatment also resulted in less occurrences of acute chest syndrome compared with placebo, according to the release.

Common adverse events of L-glutamine include constipation, nausea, headache, abdominal pain, cough, pain in the extremities, back pain, and chest pain.

Previously, L-glutamine received orphan drug designation for the treatment of patients with sickle cell disease.