MIT's Tech Review reports on Alnylam's RNAi-based drug that, with one dose, lowers cholesterol by up to 60 percent in rodents and monkeys. The drug targets PCSK9, an enzyme that had been shown to affect LDL levels and people's risk of heart disease. The RNAi drug was bundled into lipid-based nanoparticles to be transported to the liver once injected. This drug, says the article, could be used in conjunction with statins to get LDL levels even lower.