Tuesday, May 25, 2010

Alnylam Wins Important Battle in Kreutzer-Limmer Patent Fight

The Kreutzer-Limmer (KL) patent estate, exclusively owned by Alnylam and very broadly claiming double-stranded RNAs (dsRNAs) for gene silencing in human cells (up to 15-49 base pair dsRNAs), won an important battle at an oral hearing last week at the European Patent Office. This comes after Kreutzer-Limmer has suffered a number of setbacks at the EPO about one and a half years ago. The resuscitation of KL means that Alnylam may leverage this patent as potentially gate-keeping as it looks to enter additional non-exclusive licensing partners for its dominant RNAi Therapeutics patent portfolio, also as a potential backstop in the unlikely event that Alnylam loses the fight for the key Tuschl inventions.

The decision reversed an earlier rejection based on technical objections, mainly by Sirna/Merck and Silence Therapeutics, that some of the claims in the daughter application at issue had been incorrectly drawn from the parental application. In general, the main claim describing the structure of gene silencing short dsRNAs are somewhat clumsily constructed and not as straight-forward as one might imagine. This could be the result of having to take into account the embodiments underlying this claim.

If it were not be so important, reading the deeply philosophical arguments of what it means to be 'double-stranded' can be quite amusing, but unfortunately also very time-consuming and distracting, as are these drawn-out patent back-and-forths. Especially for smaller companies like Silence Therapeutics it may actually be worth focusing on developing the enabling delivery technologies and their therapeutic pipelines instead of having their lead scientists waste their creative juices taking part in these battles.

It is likely that the patent will go back again, but this time to be challenged on other issues such as novelty. Regardless, Alnylam should benefit from last week's decision to uphold Kreutzer-Limmer in that it adds to the appearance that, no matter how the individual patent chips fall, Alnylam has so many patent options that making some kind of licensing arrangement with the company would be required if one wanted to securely develop RNAi Therapeutics. Recent progress in systemic delivery should add to the urgency and may even make waiting for the outcome of the Tuschl Tussle a difficult decision.

2 comments:

wsummar said...

What would be the self life of SNALP-RNAi?

Dirk Haussecker said...

Let me answer it this way: SNALP half-life will be limiting when it comes to commercialization of the vast majority of products. It should be sufficient for most stockpiling purposes, too.

SNALP stability is certainly over 2 years (e.g. according to recent presentations by Dr. MacLachlan at DIA). I believe that this number is for room temperature, too, although I'd have to look it up again if not for 4C. The reason why it's so stable is again because of the PEGs which also prevent aggregation inside the vials.

By Dirk Haussecker. All rights reserved.

Disclaimer: This blog is not intended for distribution to or use by any person or entity who is a citizen or resident of, or located in any locality, state, country or other jurisdiction where such distribution, publication, availability or use would be contrary to law or regulation or which would subject the author or any of his collaborators and contributors to any registration or licensing requirement within such jurisdiction. This blog expresses only my opinions, they may be flawed and are for entertainment purposes only. Opinions expressed are a direct result of information which may or may not be accurate, and I do not assume any responsibility for material errors or to provide updates should circumstances change. Opinions expressed in this blog may have been disseminated before to others. This blog should not be taken as investment, legal or tax advice. The investments referred to herein may not be suitable for you. Investments particularly in the field of RNAi Therapeutics and biotechnology carry a high risk of total loss. You, the reader must make your own investment decisions in consultation with your professional advisors in light of your specific circumstances. I reserve the right to buy, sell, or short any security including those that may or may not be discussed on my blog.