Potential drug decreased viral load in patients with various HCV genotypes

Interim results from an ongoing clinical trial revealed that a microRNA therapeutic was well-tolerated and safe for the treatment of hepatitis C virus infection, according to a company release from Regulus Therapeutics.

In the trial, currently taking place in the Netherlands, RG-101 (Regulus Therapeutics), a GalNac-conjugated anti-miR targeting microRNA-122, was dosed at 2 mg/kg and given to 14 patients with HCV and various genotypes. This treatment resulted in significant and sustained reductions in HCV RNA among the patients, including those with difficult to treat genotypes and experienced viral relapse after a prior interferon-based regimen, according to the release.

“We are very excited to have demonstrated our first human proof-of-concept results with a microRNA therapeutic from the ongoing study of RG-101,” Kleanthis G. Xanthopoulos, PhD, president and chief executive officer of Regulus, said in the release. “We believe these interim data are exceptional and provide strong evidence to support the rapid advancement of RG-101 into future clinical studies, while presenting a clear opportunity for a potentially disruptive therapy to the current HCV treatment paradigm.”

According to the release, eight of the 14 patients were treatment naive and six patients who experienced viral relapse after a previous interferon-based regimen, received a single subcutaneous dose, while two patients received placebo.

Results showed a mean viral load reduction of 4.1 log10 at day 29 (range –5.8 log10 to –2.3 log10) in all 14 patients treated with RG-101; six patients had HCV RNA levels below the limit of quantification at day 29 and three patients had HCV RNA levels below the limit of quantification by day 57, the release said.

“RG-101 is the first microRNA therapeutic in clinical development to combine the most advanced RNA technologies from three leading RNA therapeutics companies; chemistry 2.5 from Isis, GalNAc conjugate from Alnylam and Regulus’ unique and proprietary chemistry, including the novel linker that facilitates the release of the parent oligonucleotide after hepatocyte uptake,” Neil W. Gibson, PhD, chief scientific officer at Regulus, said in the release.

Additional results are expected to be available in 2015, according to the release.