SomaGenics' RNA research shows promise against hepatitis C

A California biotech company and collaborators recently have published results on the efficacy of RNA-interference therapeutics against the hepatitis C virus (HCV) based on the company's sshRNA theory.

Using a mouse model with a humanized liver that supports infection by HCV, SomaGenics scientists and colleagues from Roche and Tekmira Pharmaceuticals showed efficient sshRNA delivery to the liver, potent and long-lasting reduction in viral load, and very strong evidence for a direct anti-viral effect by the sshRNAs.

These results have been published in Molecular Therapy-Nucleic Acids, Gastroenterology and in the Journal of Virology.

"The demonstration of a strong antiviral effect in the chimeric humanized-liver mouse model further reinforces our confidence in the therapeutic potential of our sshRNA platform," SomaGenics CEO Dr. Brian Johnston said. "We are quite excited about the performance of SomaGenics' synthetic sshRNAs formulated with Tekmira's LNP, which demonstrated reduction of circulating HCV load by more than two orders of magnitude and suggests that biweekly or monthly dosing could be effective. The results affirm the advantages of our approach of combining multiple sshRNAs targeting otherwise 'undruggable' viral targets. We are extending this platform to developing treatments for hepatitis (D), a serious form of viral hepatitis for which there are currently no specific treatments."

The important findings from the study include the finding that lipid-nanoparticle-formulated sshRNAs were efficiently used by human liver cells in mice, a significant HCV reduction was realized with a single IV dose, the viral load was still depressed by 1.0 log10 three weeks after dosing, the maximal anti-viral effect was observed with two doses of two sshRNAs targeting different sites on the HCV genome (a total viral load reduction of 2.5 log10 was achieved), the LNP-formulated sshRNAs were well tolerated with no evidence of liver toxicity, the therapeutic effect was demonstrated to act through an RNAi mechanism and the results demonstrate the value of a feature of RNAi approaches with the ability to easily target multiple sites on the viral genome at the same time.