The US Food and Drug Administration (FDA) has granted orphan drug designation for Global Blood Therapeutics’ (GBT) once-daily therapy GBT440 to treat patients with sickle cell disease (SCD), an inherited blood disorder.
SCD is caused by a genetic mutation in the beta-chain of haemoglobin, leading to the formation of abnormal haemoglobin known as sickle haemoglobin (HbS).
In its deoxygenated state, HbS has a propensity to polymerise or bind together forming long, rigid rods within a red blood cell (RBC).
GBT440 is currently being developed as a potentially disease-modifying therapy for SCD by increasing haemoglobin’s affinity for oxygen.
Since oxygenated sickle haemoglobin do not polymerise, the company believes GBT440 blocks polymerisation and the sickling of RBCs.
GBT440, which has the potential to restore normal haemoglobin function and improve oxygen delivery, is also expected to be capable of modifying the progression of SCD.
GBT CEO Ted Love said: "Receiving orphan drug designation, along with the previously announced fast track designation, are important milestones in our regulatory strategy for GBT440 and highlight the FDA’s agreement that the SCD community faces a critical need for new treatments.
"We continue to believe that GBT440 has the potential to become the first mechanism-based and disease-modifying therapeutic for this grievous disease and look forward to sharing full results from our Phase I/II trial and potentially initiating a pivotal trial in adult patients with SCD in 2016."
GBT discovers, develops and commercialises new therapeutics to treat grievous blood-based disorders with significant unmet need.
The company is developing its initial product candidate, GBT440, as an oral, once-daily therapy for SCD and is currently evaluating GBT440 in both healthy subjects and SCD patients in a randomised, placebo-controlled, double-blind Phase I/II clinical trial.
The company is also engaged in research and development activities targeted toward hypoxemic pulmonary disorders, including idiopathic pulmonary fibrosis (IPF) and acute respiratory distress syndrome (ARDS), as well as hereditary angioedema (HAE).