Poly(A).poly(U) as adjuvant in cancer treatment distribution and pharmacokinetics in rabbits

Rabbits were injected with poly(A).poly(U) and the metabolic fate and stability studied using scintigraphic techniques, radioactive counting, and subcellular fractionation. The complex has a very long lifetime (measured in days) in both liver and spleen, the major locations of concentration in the animal, with about nine times more per gram of tissue in the spleen compared with the liver. In spleen cells the material is about equally divided between nuclei and cytoplasm. The polymer is slowly degraded to shorter molecules in these cells but, even 1 week after injection, significant amounts of apparently intact polynucleotide complex can be detected in both cellular fractions.