1. One method for treating sickle cell anemia is to reduce the concentration of defective hemoglobin by stimulating the body to make other kinds of hemoglobin.
Hydroxyurea
Hydroxyurea (Droxia), a cancer medication, has been shown to reduce pain and complications in sickle cell anemia in adults. It is still being investigated for use in children, with special concern for how hydroxyurea may affect child growth and development.
[Wang, W. C., Helms, R. W., Lynn, H. S., et al. (2002) Effect of hydroxyurea on growth in children with sickle cell anemia: Results of the HUG-KIDS study. Journal of Pediatrics 140(2), pp 225-229]
Butyrate, arginine
Two other drugs being investigated to stimulate hemoglobin production are butyrate and arginine. Studies have shown both drugs not only increase healthy hemoglobin but reduce the symptoms of sickle cell anemia as well.
[Armandola, E. A. (2002). Management of sickle cell anemia: New approaches. 7th Congress of the European Hematology Association.]
2. Since the pain of sickle cell anemia comes from blood vessels being blocked off, another method of treatment would be to get more oxygen to the painful areas.
Poloxamer 188
Poloxamer 188 (Flocor), made by CytRx Corp., has been shown in studies to decrease the length of painful episodes in sickle cell anemia by improving blood flow in the tiny blood vessels around the painful area. In June 2001 the U.S. Food and Drug Administration (FDA) granted CytRx permission to put Flocor on the fast track for development, for treatment of acute chest syndrome.
[Marlowe, K. F., & Chicella, M. F. (2002). Treatment of sickle cell pain. Pharmacotherapy 22(4), pp. 484-491.]
3. Sickled red blood cells could also be made less "sticky" and thus less likely to block off blood vessels.
Sulphasalazine
A study published in 2001 showed that the drug sulphasalazine could reduce the number of "sticky" molecules on red blood cells in sickle cell anemia.
[Solovey, A. A., Solovey, A. N., Harkness, J., & Hebbel, R. P. (2001). Modulation of endothelial cell activation in sickle cell disease: A pilot study. Blood 97, pp. 1937-1941.]
4. The gene that causes red blood cells to sickle was identified more than 40 years ago. Researchers are looking at two methods of using that knowledge for gene therapy:
- take out some of the person's cells, "fix" the defective gene, and put it back in the bone marrow so that only the correct version of the gene will be made
- figure out how to "turn off" the defective gene and "turn on" another gene that makes healthy hemoglobin
