What is the availability of treatment for sickle cell anemia in developed and underdeveloped countries?

Sickle cell: Treatment for sickle cell anemia is mainly supportive care- such as hydroxy urea, blood transfusion, hydration, iron chelating agent, pain support for crisis, o2 etc. These supportive treatment are available everywhere-in develop/underdeveloped countries. Bone marrow transplantation is the only thing that can cure sickle cell anemia. In underdeveloped countries- this option may not be available.