Medication Monitor

Generic Name (Trade Name—Company)
August 30, 2015


FDA extends use of drug in young children with rare blood disorder

FDA approved eltrombopag to treat low blood platelet count in pediatric patients aged 1 year and older with chronic immune thrombocytopenic purpura (ITP), a rare blood disorder. The agent can be used in these children when they have not achieved an appropriate response using other ITP medicines or surgery to remove the spleen.

ITP is a disorder that results in an abnormally low number of platelets. Without enough platelets, bleeding can occur under the skin, in mucous membranes (such as in the mouth) or in other parts of the body.

Eltrombopag helps increase blood platelet production and is available as a tablet taken once-daily or as a powder that is mixed with liquid for children aged 1 to 5 to take orally. It was first approved in 2008 to treat adult patients with the same condition as the new pediatric indication.

The agent should be used only in patients with ITP whose degree of thrombocytopenia and clinical condition increase the risk for bleeding.

Efficacy and safety of eltrombopag in pediatric patients aged 1 to 17 years with chronic ITP was evaluated in two double-blind, placebo-controlled trials of 159 participants where the primary endpoint was an increase in platelet counts.

In the first trial (n = 67), patients were randomly assigned to receive either eltrombopag or placebo daily for 7 weeks. Of those taking eltrombopag, 62% had an improvement in platelet counts without rescue therapy between weeks 1 and 6, compared with 32% in the placebo group.

In the second trial (n = 92), patients received either eltrombopag or placebo daily for 13 weeks. In those treated with eltrombopag, 41% experienced increased platelet counts for at least 6 out of 8 weeks between weeks 5 to 12, compared with 3% of patients receiving placebo.

In both trials, patients taking eltrombopag also had less need for other treatments to increase their platelet counts, such as corticosteroids or platelet transfusions. Among patients taking one or more ITP medications at the start of the trials, about one-half were able to reduce or discontinue their use of these medications, primarily corticosteroids.

The most common adverse effects of treatment in children aged 1 and older were infections of the upper respiratory tract or nose and throat (symptoms including fever, cough, nasal congestion, runny nose, and sore throat), diarrhea, abdominal pain, rash, and increase in liver enzymes.

Safety and efficacy of eltrombopag in pediatric patients younger than 1 year with ITP, or in pediatric patients with thrombocytopenia associated with chronic hepatitis C and severe aplastic anemia, have not been established.

FDA granted eltrombopag orphan drug designation because it treats a rare disease.