The National Heart, Lung, and Blood Institute announced the premature termination of TWiTCH, its clinical trial of children with sickle cell disease, because researchers met their goal ahead of schedule.

The NHLBI stated in a press release that the trial was stopped in agreement with the recommendations of the Data and Safety Monitoring Board (DSMB) – an independent group of experts that regularly reviews accumulating data from ongoing clinical trials and makes recommendations to investigators and sponsors on how to move forward.

“The DSMB’s planned first interim analysis of the TWiTCH study data indicated that the study had reached its primary and most important endpoint,” the NHLBI said in the statement. “As such, they recommended that the study end due to early results, particularly given that the strength of the statistical finding was unlikely to change with the collection of additional data.”

TWiTCH (Transcranial Doppler with Transfusions Changing to Hydroxyurea) was a phase III clinical trial created to determine whether daily doses of hydroxyurea lower the transcranial Doppler (TCD) blood velocity in children with sickle cell disease with the same efficacy as that of blood transfusions. Currently, hydroxyurea is the only Food and Drug Administration–approved drug for sickle cell disease, a disorder that affects children and puts them at increased risk for stroke if they have high TCD blood flow velocities.

According to the data accrued by the researchers prior to the study’s termination, hydroxyurea was found to be “not inferior to (that is, no worse than) regular blood transfusions in lowering TCD velocities in children with sickle cell disease who are at high risk for stroke.”

“The results of TWiTCH will allow the families of children with sickle cell disease and who are at increased risk of stroke, to choose between two equally effective preventive therapies,” Dr. Keith Hoots, director of the NHLBI’s division of blood diseases and resources, said in an interview. “The TWiTCH trial is the most recent example of NHLBI’s ongoing commitment to the development of new therapies for the prevention and treatment of stroke in children with sickle cell disease.”

According to information from the American Society of Hematology , the trial included 25 participating centers from around the United States, and was funded by the NHLBI with sponsorship from Cincinnati Children’s Hospital Medical Center.