Solstar Pharma has developed an siRNA platform technology using proprietary modified nucleic acid chemistry. Our modified nucleotides enhance the stability and optimize the mRNA target activity of our siRNAs.
We are harnessing the power of siRNA to inhibit pathogen replication such as in coronavirus disease or block the production of cancer-causing proteins.
Gene-based nucleic acid therapeutic technologies, such as RNA interference (RNAi), for sequence-specific target mRNA degradation, include small interfering RNA (siRNA). These oligonucleotide therapeutics are applied to direct mRNA degradation. We focus on siRNA-based therapeutics by applying our modified nucleotide platform technology.
Step 1
siRNA enters the cell as a double stranded RNA molecule
Step 2
One siRNA strand is recruited by the RISC complex
Step 3
RISC + siRNA binds to a complementary mRNA
Step 4
mRNA is cleaved in a specific site
Step 5
Cleaved mRNA is degraded in the cell
Target any gene
Stable against nucleases
Enhanced activity
Multiple delivery approaches
Target any gene
Our siRNAs are designed using sequence algorithms and optimized to target specific disease-causing genes.
Stable against nucleases
Our proprietary modified nucleotides used in the synthesis of siRNA show enhanced stability and resistant against nucleases
Enhanced activity
Our modified nucleotides can be combined with currently available chemical modifications to optimize the siRNA target effect
Multiple delivery approaches
Our optimized siRNAs can be delivered with ligand-specific moieties to target a particular cell/organ
SOLSTAR Modified Nucleotides
Solstar Pharma has developed novel nucleotides that contain modifications on the ribose sugar, 5′-C-aminopropyl-2′-O-methyl, which are applicable to siRNAs. These monomers significantly increase the stability of siRNAs by protecting them from nucleolytic degradation.
Structure of 5′-aminopropyl-nucleotides (5’ AA-Nt)
RNA interference agent, multiple chemically modified oligonucleotide, and use thereof
STATUS: Examination
Scientific
References
siRNA Mechanism
4′-C-Aminoethoxy modification enhanced nuclease resistance of RNAs and improved thermal stability of RNA duplexes
Tsukimura, R., Kajino, R., Zhou, Y., Chandela, A., Ueno, Y.*: 4′-C-Aminoethoxy modification enhanced nuclease resistance of RNAs and improved thermal stability of RNA duplexes. Results in Chemistry 3: 100231, 2021.
(S)-5'-C-Aminopropyl-2'-O-methyl nucleosides enhance antisense activity in cultured cells and binding affinity to complementary single-stranded RNA
Kajino, R. and Ueno, Y.*: (S)-5′-C-Aminopropyl-2′-O-methyl nucleosides enhance antisense activity in cultured cells and binding affinity to complementary single-stranded RNA. Bioorg. Med. Chem. 30: 115925, 2021.
Synthesis and evaluation of (S)-5'-C-aminopropyl and (S)-5'-C-aminopropyl-2'-arabinofluoro modified DNA oligomers for novel RNase H-dependent antisense oligonucleotides
Zhou, Y., Kajino, R., Ishii, S., Yamagishi, K. and Ueno, Y.*: Synthesis and evaluation of (S)-5′-C-aminopropyl and (S)-5′-C-aminopropyl-2′-arabinofluoro modified DNA oligomers for novel RNase H-dependent antisense oligonucleotides. RSC Advances 10: 41901-41914, 2020.
4'-C-Aminomethyl-2'-deoxy-2'-fluoroarabinonucleoside increases the nuclease resistance of DNA without inhibiting the ability of a DNA/RNA duplex to activate RNase H
Tsuchihira, T., Kajino, R., Maeda, Y. and Ueno, Y.*: 4′-C-Aminomethyl-2′-deoxy-2′-fluoroarabinonucleoside increases the nuclease resistance of DNA without inhibiting the ability of a DNA/RNA duplex to activate RNase H. Bioorg. Med. Chem. 28: 115611, 2020.
Synthesis and characterization of 4'-C-guanidinomethyl-2'-O-methyl-modified RNA oligomers
Uematsu, A., Kajino, R., Maeda, Y. and Ueno, Y.*: Synthesis and characterization of 4′-C-guanidinomethyl-2′-O-methyl-modified RNA oligomers. Nucleotides & Nucleic Acids 39: 280-291, 2020.
Synthesis and biophysical characterization of RNAs containing (R)- and (S)-5'-C-aminopropyl-2'-O-methyluridines
Kajino, R., Maeda, Y., Yoshida, H., Yamagishi, K. and Ueno, Y.*: Synthesis and biophysical characterization of RNAs containing (R)- and (S)-5′-C-aminopropyl-2′-O-methyluridines. J. Org. Chem. 84: 3388-3404, 2019.
Synthesis and properties of 4'-C-aminoalkyl-2'-fluoro-modified RNA oligomers
Kano, T., Katsuragi, Y., Maeda, Y. and Ueno, Y.*: Synthesis and properties of 4′-C-aminoalkyl-2′-fluoro-modified RNA oligomers. Bioorg. Med. Chem. 26: 4574-4582, 2018.
Synthesis of 4'-C-aminoalkyl-2'-O-methyl modified RNA and their biological properties
Koizumi, K., Maeda, Y., Kano, T., Yoshida, H., Sakamoto, T., Yamagishi, K. and Ueno, Y.*: Synthesis of 4′-C-aminoalkyl-2′-O-methyl modified RNA and their biological properties. Bioorg. Med. Chem. 26: 521-3534, 2018.