Eltrombopag is thought to stimulate megakaryocytes, the bone marrow cells that produce blood platelets. The drug, also called Promacta, is being developed by GlaxoSmithKline, which funded both studies.
For the first study, 118 people with ITP and low platelet counts were randomized to receive 30, 50 or 75 milligrams of eltrombopag or a placebo. All participants had failed at least one previous treatment.
A platelet count of 50,000 or more per cubic millimeter on day 43 was achieved in 28 percent, 70 percent and 81 percent of participants who received 30, 50 and 75 milligrams of eltrombopag respectively.
Only 11 percent of those in the placebo group reached this level.
By day 15 of the trial, more than 80 percent of patients receiving 50 or 75 milligrams of eltrombopag daily had an increased platelet count. These individuals also experienced decreased bleeding.
For the second study, 74 patients with HCV-related cirrhosis and low platelet counts were randomly assigned to receive 30, 50 or 75 milligrams of eltrombopag daily or a placebo for four weeks.
"Hepatitis C is clearly a big problem. It's the most common cause for liver transplantation and the commonest cause of cirrhosis," McHutchison said. "We have treatments out there approved but people with more advanced liver disease and low platelet counts were excluded from the registration trial [for FDA approval]."
By week four, 75 percent of those receiving 30 milligrams of eltrombopag, 79 percent of those receiving 50 milligrams and 95 percent of those receiving 75 milligrams of eltrombopag had platelet counts of 100,000 per cubic millimeter or more. By contrast, none of those receiving the placebo saw their counts increase to that level.
Twelve weeks of antiviral therapy with peginterferon
All rights reserved