Roughly three years after partnering with Quark Pharmaceuticals to develop siRNA-based treatments for fibrotic diseases, Japan’s Nitto Denko has initiated its first clinical trial of an RNAi drug.
The drug, called ND-L02-s0201, uses vitamin A-coupled lipid nanoparticles to deliver siRNAs targeting heat shock protein 47, a collagen-specific chaperone required for the biosynthesis and secretion of collagen.
As previously reported, Nitto Denko inked a deal in mid-2010 to combine its delivery technologies with Quark’s siRNA design expertise and intellectual property to develop anti-fibrotic therapies (GSN 7/15/2010).
Now, Nitto Denko has moved a drug candidate from that arrangement into a placebo-controlled phase I study, which will examine the safety and tolerability of single, ascending intravenous doses of ND-L02-s0201 in healthy volunteers.
The trial is expected to enroll 58 people, with data related to its primary outcome measures available in early 2014.
Few details about ND-L02-s0201 have been made public. However, in 2008, Nitto Denko and academic collaborators reported data in Nature Biotechnology on the delivery of HSP47-targeted siRNAs via vitamin A-coupled liposomes to treat liver fibrosis.
According to that paper, the delivery approach takes advantage of hepatic stellate cells’ “remarkable capacity for vitamin A uptake, most likely through receptors for retinol binding protein.” The RNAi component, meantime, is designed to inhibit collagen synthesis, thereby reversing liver fibrosis.
Treatment with the siRNA-loaded liposomes “almost completely resolved liver ﬁbrosis and prolonged survival in rats with otherwise lethal dimethylnitrosamine-induced liver cirrhosis in a dose- and duration-dependent manner,” the study’s authors wrote. Additionally, the drug was also effective in suppressing collagen secretion and treating fibrosis induced by CCL4 or bile duct ligation.