FDA grants orphan drug designation to GBT 440 for sickle cell disease

The FDA granted orphan drug designation to GBT440 for the treatment of patients with sickle cell disease, according to a press release from the drug’s manufacturer.

GBT440 (Global Blood Therapeutics) — a novel, oral small molecule hemoglobin modifier — increases hemoglobin oxygen affinity.

Preclinical data indicated the therapy is a potent anti-sickling agent with a high specificity for hemoglobin.

Data presented at the ASH Annual Meeting and Exposition demonstrated that patients treated with GBT440 experienced a greater median change from baseline to day 28 in hemoglobin (500-mg dose, 0.5 g/dL; 700-mg dose, 0.7 g/dL) than those who received placebo (–0.1 g/dL). GBT440-treated patients also demonstrated greater median changes in erythropoietin levels (500-mg dose, –9 mU/mL; 700-mg dose, –18 mU/mL; placebo, +28 mU/mL) and reticulocyte count (500-mg dose, –31%, 700-mg dose, –37%; placebo, +7%).

Analysis of peripheral blood smears showed a pronounced reduction in the number of sickle cells (500-mg dose, –56%; 700-mg dose, –46%) among those treated with GBT440 compared with placebo (+14%).

The FDA Office of Orphan Products Development grants orphan drug designation to novel drugs and biologics that are intended for the safe and effective treatment, diagnosis or prevention of rare diseases or disorders that affect fewer than 200,000 people in the United States.

“We continue to believe that GBT440 has the potential to become the first mechanism-based and disease-modifying therapeutic for this grievous disease,”

Ted W. Love, MD, CEO of Global Blood Therapeutics, said in the release. “[We] look forward to sharing full results from our phase 1 and phase 2 trial, and potentially initiating a pivotal trial in adult patients with sickle cell disease in 2016.”