Inex Pharmaceuticals President and CEO Timothy Ruane this week reiterated the company's belief that it owns an oligonucleotide delivery technology at the heart of a legal battle with Protiva Biotherapeutics and involving the two biggest players in the RNAi therapeutics space: Sirna Therapeutics and Alnylam Pharmaceuticals.
Ruane's comments, which were made during a conference call to announce an agreement for the settlement of the company's convertible debt (see sidebar), also suggested that Inex may be looking to build off a recent deal with Alnylam to evaluate use of the delivery technology with siRNAs and sign partnerships in other oligo-based drug fields such as antisense and toll-like receptors.
"Inex began developing its lipid-encapsulated oligonucleotide delivery platform in 1992 when we were encapsulating plasmids as part of our gene therapy research," Ruane said during the call. "Since that time, we've conducted [research and development] using liposomes as a true enabling technology for the systemic delivery of different types of oligonucleotides including ribozymes, antisense, RNA and DNA constructs, and most recently small interfering RNAs.
"Given this breadth of research, we've developed a comprehensive patent portfolio covering the liposomal delivery of all types of oligonucleotides, and today we have 77 issued patents and 96 pending applications in this field," he added. "We believe we are well-positioned in this emerging field."
"We've developed a comprehensive patent portfolio covering the liposomal delivery of all types of oligonucleotides, and today we have 77 issued patents and 96 pending applications in this field. We believe we are well positioned in this emerging field."
The technology at issue — termed SNALPs, for stable nucleic acid lipid particles — involves the encapsulation of oligos by cationic and fusogenic lipids, which are surrounded by a polyethylene glycol coating to prevent clearance of the positively charged cationic lipid from the bloodstream.
While it is agreed that the foundation for SNALPs was built at Inex, the ownership of the technology for use in RNAi is in dispute. According to Inex, in 2001 it spun out Protiva to develop a gene-delivery technology for cancer and inflammatory diseases using "all assets relating to [Inex's] proprietary gene-delivery technology."
That technology was developed into SNALPs, and by 2003 Protiva was shopping it around for RNA-based therapeutic applications (see RNAi News, 11/7/2003), eventually landing a partner in Sirna.
Since then, however, Sirna has withdrawn from its alliance with Protiva, filing a lawsuit in March alleging that Protiva never held the rights to SNALPs in RNAi (see RNAi News, 3/2/2006). Protiva countersued Sirna that same month, charging that its one-time partner stole trade secrets in order to develop its own delivery technology (see RNAi News, 3/30/2006). Protiva also sued Inex for inappropriately claiming ownership of the SNALP technology, thereby scuttling its deal with Sirna and potential deals with other RNAi firms.
Things have since gone from bad to worse for Protiva since: The same week Alnylam published data showing SNALPs were successfully used to deliver its siRNAs systemically in non-human primates, the company said it would be evaluating a liposomal-based drug-delivery technology from Inex (see RNAi News, 3/30/2006).
Then, last month, Inex countersued Protiva to assert its ownership of SNALPs in the RNAi field.
During the conference call, Ruane said he would not comment on the ongoing litigation. His comments, however, did indicate that Inex continues to believe it owns the rights to the SNALP technology.
Inex has "exciting research, advanced manufacturing and development experience, and an extensive patent position in the lipid-encapsulated oligonucleotide field," he said. "Our position … has not gone unnoticed. On March 27 of this year, Inex announced … an exclusive research collaboration agreement and exclusive option on a global licensing agreement with Alnylam."
That deal "provides significant research funding to Inex in the near term, and if things continue to progress well and Alnylam triggers the license agreement, Inex would receive up-front license fees, future milestones, and royalty participation as products are commercialized," Ruane said.
"More importantly, we believe the Alnylam collaboration validates our robust oligonucleotide delivery platform, and both our IP and contractual positions," he said. "In the short 12 weeks since the Alnylam announcement … our team has executed ahead of schedule and we have successfully encapsulated Alnylam's RNAi-based oligonucleotides and have already delivered these formulations to Alnylam for evaluation. The early results look promising."
Ruane told RNAi News that he would not comment beyond his statements during the conference call. It therefore remains unclear whether the company is exploring deals similar to the one with Alnylam in oligo-based therapeutic areas beyond RNAi.
But Ruane made a point of noting during the call that "companies such as Coley [Pharmaceuticals], Alnylam, and Sirna … [are] all actively seeking novel technologies to facilitate the systemic delivery of their oligonucleotide-based payloads."