A scientist from the National Institutes of Health will present promising, early results from a human clinical trial testing a novel gene replacement therapy in people with severe sickle cell disease. Preliminary findings suggest that the approach has an acceptable level of safety and might help patients consistently produce normal red blood cells instead of the sickle-shaped ones that mark this painful, life-threatening disease.

The experimental treatment involves removing hematopoietic stem cells from the patients’ bone marrow or blood and adding a therapeutic beta globin gene, which is defective in people with sickle cell disease. The cells are then returned to the patients, leading to the production of anti-sickling hemoglobin (T87Q).

Current data from the ongoing HGB-206 phase 1 multicenter nationwide study will be presented at the 60th Annual Meeting of the American Society of Hematology (ASH), December 1-4, in San Diego.

People with sickle cell disease often suffer severe pain because the sickled red blood cells clump together and become stuck in blood vessels. The condition can cause stroke, organ failure, and early death. More than 100,000 people in the US and 20 million worldwide suffer from the disease.

Based on preliminary findings, researchers believe the new gene replacement therapy will enable the patients’ bone marrow to produce normal red blood cells consistently. The trial is currently recruiting patients.

This study is part of decades of research on sickle cell disease that have opened the door to novel genetic approaches to curative therapies. In September, the National Heart, Lung, and Blood Institute (NHLBI), part of NIH, launched the Cure Sickle Cell Initiative to speed up the movement of the most promising of these therapies into clinical trials within five to 10 years.

At the ASH Presidential Symposium on Tuesday, Dec. 4, NIH Director Francis S. Collins, MD, PhD, will discuss the Cure Sickle Cell Initiative. He will describe how advances in our knowledge of hematologic conditions, the biology of viral vectors and target cells, and the development of methods to genetically modify cells are accelerating this field of study.