The US Patent & Trademark Office (USPTO) has granted three patents covering portions of Tekmira Pharmaceuticals' technology that protect aspects of Tekmira's lipid nanoparticle technology (LNP), which are used to deliver nucleic acid drugs, including small interfering RNA (siRNA).

Specifically, the USPTO has issued claims in three patents covering LNP formulations and lipid components used in Tekmira’s LNP formulations.

This includes two issued patents covering the cationic lipid DLinDMA and related cationic lipid analogues (US Patent No 7,745,651) as well as LNP formulations containing these novel cationic lipids (US Patent No 7,799,565).

The third issued patent covers a class of lipid conjugates, PEG-C-DAAs (US Patent No 7,803,397). PEG-C-DAAs are another critical component of Tekmira’s LNP technology that are important in the manufacturing and stability of LNP formulations and the performance of the formulations in-vivo.

Tekmira claims that its LNP technology (formerly referred to as stable nucleic acid-lipid particles or SNALP) encapsulates siRNAs with high efficiency in uniform lipid nanoparticles which are effective in delivering RNAi therapeutics to disease sites in numerous preclinical models.

Tekmira president and CEO Mark Murray said that Tekmira’s LNP formulations are the gold standard for siRNA delivery and the issuance of these patents is a key step in the successful commercialisation of this technology by Tekmira and partners.

“These new patents cover key components of our LNP technology, which is already well validated in preclinical studies and is currently part of multiple clinical development programs sponsored by Tekmira and Tekmira’s partners,” Murray said.