The combination chemotherapy regimen of gemcitabine and docetaxel has become an increasingly used treatment choice for subjects with advanced sarcomas. The regimen has shown activity in first and second line for subjects with metastatic uterine leiomyosarcoma, relapsed/refractory pediatric sarcomas, and improved progression-free survival and overall survival in persons with metastatic sarcoma when compared to gemcitabine alone. The regimen has additionally been recognized as a treatment option for subjects with advanced sarcoma.~Chemotherapy-induced toxicity in the blood such as low platelet level is a common and often therapy-limiting side effect of treatment.~There are two phases in this study. The purpose of the Phase I study is to determine the recommended dose of eltrombopag. The purpose of the Phase II study is to determine the safety, tolerability, and efficacy (how well the drug works) of eltrombopag in subjects who are receiving gemcitabine and docetaxel chemotherapy.~Eltrombopag (Promacta) is an FDA approved drug for the treatment of chronic idiopathic thrombocytopenic purpura (ITP)- a condition of having an abnormally low platelet count. Eltrombopag is now being further investigated for other thrombocytopenic (low platelet)disorders.~Participants will take the assigned dose of eltrombopag once a day starting five days before each cycle of chemotherapy and for 5 days after chemotherapy. Eltrombopag is not taken on the day of chemotherapy. Eltrombopag is taken orally.
The purpose of this study is to study the effect of eltrombopag on chemotherapy induced thrombocytopenia. Thrombocytopenia is when there is a low number of platelets in the blood. Sometimes, thrombocytopenia occurs as a side effect of chemotherapy treatments.