Abstract: Pharmaceutical compositions are provided which comprise a lactone form of camptothecin, or a lactone form analog thereof that is effective for controlling abnormal cell proliferation; and at least one amphiphilic block copolymer that, upon oral administration to a patient, increases oral bioavailability of the lactone form significantly more than that of a directly related carboxylate form of the camptothecin or analog thereof. Compositions are also provided that further comprise at least one bioadhesive polymer that protects a closed alpha-hydroxy lactone structure of the lactone form of camptothecin or analog thereof, and provides a controlled release of the lactone form of camptothecin or lactone form analog thereof, in GI, upon oral administration to a patient. Methods are described for the prevention and/or treatment of a condition related to abnormal cell proliferation comprising orally administering to a patient in need of thereof an effective amount of a composition of the present invention.