Achebe explains the promising results of the open label extension to the HOPE trial for patients with sickle cell disease.
Maureen Achebe, MD, MPH, Assistant Professor of Medicine, Hematology, Brigham and Women's Hospital, presented the interim analysis of the open label extension of the HOPE trial at the 2021 American Society of Hematology (ASH) Annual Meeting & Exposition.
"HOPE was a randomized control trial that examined the use of voxelotor for sickle cell disease (SCD)," Achebe said. "Voxelotor itself is a molecule that increases hemoglobin's affinity for oxygen, currently indicated for patients with sickle cell disease and anemia."
The trial showed a significant increase in hemoglobin in patients who received voxelotor, supporting the investigators' primary outcome.
"In patients who had benefited from voxelotor, or other patients who had completed voxelotor," Achebe explained, "there was an open label extension that was offered to patients to continue on voxelotor before the anticipated FDA approval of the medication."
At the conclusion of HOPE, the 1500 milligram dose of voxelotor had reached the investigators' primary endpoint. They wanted to further examine if the patients who received 900 milligrams, or the patients who were previously on placebo, would also benefit at the 1500 milligram dose.
"By the end, or by our interim analysis," Achebe said, "about 78 patients had been on voxelotor for a total of 144 weeks without any unexpected side effects, even with that long term use."
The investigators are continuing to follow these patients to determine if they display sustained increases in hemoglobin.
"You know, a drug that increases hemoglobin oxygen affinity raises the concern of whether it will appropriately deliver oxygen to tissues when the tissues need the oxygen," Achebe said. "So far, there hasn't been a signal that there's tissue hypoxia, and we will continue to watch patients as it's still a relatively new drug, just FDA approved in November 2019."