WASHINGTON -- Researchers have discovered that a drug being examined as a cancer therapy may also turn out to be a non-toxic treatment for sickle cell anemia and related blood disorders.
Scientists at Johns Hopkins School of Medicine and the National Cancer Institute said yesterday that the drug, which is commonly used for rare metabolic disorders in children, has been found to increase production of a fetal type of hemoglobin that is beneficial to sickle cell patients.
The researchers said they know of no other drug that produces such a high level of fetal hemoglobin, and they are excited about its potential for treating patients who suffer from inherited anemias.
Hemoglobin is the oxygen-carrying protein of red blood cells. In sickle cell anemia, abnormal blood cells turn rigid, assume a sickle shape and block vessels.
Researchers have found that phenylacetate, a naturally occurring chemical in the body that is known to be non-toxic at high doses, sharply increases production of the fetal hemoglobin. The finding is so promising that doctors at Johns Hopkins quickly received approval from the Food and Drug Administration to conduct an initial human trial with anemia patients of phenylbutyrate, a drug that produces phenylacetate in the body.
"It is very unusual for work to move so rapidly from the laboratory to clinical tests, but this is an unusual case," said Dr. Dvorit Samid of the National Cancer Institute, one of the researchers.
Dr. Samid contacted Dr. Saul Brusilow of Johns Hopkins, who had developed a form of the compound to treat children with inherited metabolic disorders.