Prolong Pharmaceuticals has completed enrolling patients in an ongoing Phase 2 clinical trial of Sanguinate, a treatment for the painful blocked blood vessel episodes that occur in sickle cell disease.
The cause of the episodes, known as vaso-occlusive crises, is abnormally shaped red blood cells bunching up and blocking blood flow through arteries. Sanguinate is designed to prevent the clumping, keeping blood flowing.
The hallmark of sickle cell disease is faulty hemoglobin, the blood cell protein that transports oxygen from the lungs to tissues and organs, and carbon dioxide back to the lungs. The abnormal hemoglobin leads to red blood cells becoming shaped like a sickle instead of round.
Such cells are unable to carry as much oxygen as tissue and organs need. And they can bunch up and impair blood flow.
The trial (NCT02411708) is assessing Sanguinate’s safety and ability to treat vaso-occusive crises. The company hopes to have full results in the first half of 2018.
Prolong presented preliminary trial results in a poster session at the 59th American Society of Hematology convention in Atlanta, Dec. 9-12. They showed that Sanguinate can return red blood cells from a sickle shape back to a round shape, restoring blood flow.
“The potential for restoration of normal RBC [red blood cell] shape is important because VOC [a vaso-occusive crisis] occurs when sickle-shaped RBCs — the hallmark of SCD — block blood vessels and restrict blood flow, thereby depriving body tissues and organs of oxygen,” Dr. Ronald Jubin, Prolong Pharmaceuticals’ vice president of research and development, said in a press release. “This complication can damage the tissues and organs, causing severe pain. The data interpretation presented at ASH [the Atlanta conference] is preliminary, and the full data set from the Phase 2 trial of Sanguinate remains to be analyzed. Further nonclinical [non-trial study] and clinical evaluations are required to explore these findings in more detail.”
In another Atlanta poster presentation, Prolong reported that Sanguinate resolved vaso-occusive crises in mice with sickle cell diease, improving blood flow so that tissue and organs could obtain the oxygen they needed.
Other studies have also shown that Sanguinate can resolve vaso-occusive crises so that oxygen delivery returns to near-normal levels.
“The sickle cell community continues to follow Sanguinate with great interest, as the latest research appears to support the rationale for further clinical assessment of this agent to manage acute VOC in individuals with SCD,” said Lanetta Bronte, president of the Foundation for Sickle Cell Disease Research. “We look forward to the final data analysis from the Sanguinate clinical program,” added Bronte, co-investigator of the Phase 2 trial.
The U.S. Food and Drug Administration has designated Sanguinate an orphan drug — a status that gives companies incentives to develop therapies for rare diseases. The designation applies to Sanguinate as a possible treatment for vaso-occusive crises, stroke and acute chest syndrome, a potentially life-threatening lung-related complication of sickle cell disease.