The trial will have an 80% statistical power at the 5% level of significance (two sided) to detect a difference in the proportion of subjects receiving increased dose of eltrombopag with a primary response (2 consecutive platelet counts of > 50,000 and an increase of > 20,000 from the study baseline with in the 8 week increased dose window not as a result of rescue treatment ) to subjects without a primary response in the placebo group assuming 50% of subjects randomized to active drug will have a response and 5% of subjects randomized to placebo would have a response. However an interim analysis would be performed after 18 subjects to test for futility and efficacy and also to re-estimate sample size. If neither futility or efficacy are met the trial would continue to enroll. Based on the observed treatment effect at the interim analysis the sample size would be allowed to expand to up to 60 subjects.