The invention provides processes for the producing compositions comprising (i) a virus-like particle, wherein said virus-like particle is a virus-like particle of an RNA bacteriophage, and (ii) an oligonucleotide, wherein said oligonucleotide is packaged into said virus-like particle. The invention further provides processes for producing nucleotide compositions comprising oligonucleotides suitable to be used in the processes mentioned before. The invention further provides nucleotide compositions obtainable by the processes of the invention and uses thereof. The invention further provides compositions comprising (i) a virus-like particle, wherein said virus-like particle is a virus-like particle of an RNA bacteriophage, and (ii) an oligonucleotide, wherein said oligonucleotide is packaged into said virus-like particle, wherein said compositions are obtainable by the processes of the invention and wherein said compositions preferably comprises a purity of at least 98%, most preferably of at least 99%.