my brothers kidney cancer

My brother had his kidney removed in May and had several mets. to the lungs. Since then he was on a hormone therapy that did not seem to work. He is now on sutent and I am praying this works. He has only been on it for a week and no side effects yet. What are the chances of this working? Will he have to be on this forever and what if it doesnt work what will they try next? He was told by the doctor that he is in the latter stages of stage iv? Is that bad or does he have a fighting chance!!God Bless Everyone!! Carolanne