The present invention provides compositions and methods of treatment of diseases that are sensitive to drugs that downregulate the function of microRNA's, mRNA, non-coding RNA, or viral genomes. In particular, it has been discovered that a very long term effect of an anti microRNA oligonucleotide may be obtained when administered to a primate. Therefore, the present invention relate to pharmaceutical compositions and methods for treatment of primates, including humans wherein the compositions are administered with a long time interval.