Phase III clinical trial results of the triple therapy combination for the treatment of severe aplastic anemia (SAA) were set forth in a recent News Medical Life Sciences article.
The European Society for Blood and Marrow Transportation (EBMT) initially announced the results at its virtual 2020 Annual Meeting stating that eltrombopag added to an immunosuppressant increases SAA patients’ response rate.
About SAA
Severe aplastic anemia occurs when the bone marrow is not able to create a sufficient amount of blood cells. This rare and sometimes fatal disorder can be improved by a bone marrow transplant.
Some patients may be ineligible for a transplant, but their condition may improve with immunosuppressive therapy.
Injecting Horses With Thymocytes
One of the more common immunosuppressive regimens for SAA includes r-ATG plus Cyclosporin A, an immunosuppressive drug.
R-ATG is produced by injecting horses with thymocytes, which are a type of human white blood cell. The horse’s immune system responds by producing antibodies that kill the thymocytes. The antibodies are then collected, purified, and developed into r-ATG.
However, about thirty-five percent of patients are unresponsive to the treatment.
Note: initial studies comparing r-ATG (rabbit) to h-ATG (horse) in aplastic anemia patients have shown conflicting results. A series of later studies have concluded that there is no significant difference in survival or treatment response between r-ATG and h-ATG.
About Eltrombopag
Eltrombopag is one of two thrombopoietin receptor agonists that are approved for the treatment of thrombocytopenia (low platelets). Studies have recorded a positive response of between fifty and ninety percent.
A more recent trial confirms that when eltrombopag is added to standard immunosuppression, the combination brings about a significant response rate when compared to standard immunosuppression therapy alone.
The Phase III Clinical Trial for SAA
The trial involved 197 SAA patients aged fifteen years or older. The patients had not been treated previously with immunosuppressive therapy.
The subjects received standard immunosuppression or standard immunosuppression with the addition of Eltrombopag.
At the three-month interval, the patients who had been treated with the triple combination of h-ATG, Cyclosporin A, and eltrombopag, showed a much more prominent complete response than those patients given h-ATG and Cyclosporin. The response remained stable at the six-month interval.
Eltrombopag was safe and well-tolerated. The study team will be monitoring the trial participants for two years with plans to extend the period of monitoring for a total of ten years.
