Sirna Granted Patent for RNAi Production

Sirna Therapeutics, Inc. (Nasdaq: RNAI), announced today that the U.S. Patent and Trademark Office has granted Patent No. 6,989,442 for the chemical synthesis and manufacturing of ribonucleic acids. The patent broadly covers a process for the synthesis, deprotection and purification of nucleic acids with one or more ribonucleotides.

This process is critical for the efficient synthesis of RNA at high yields and high purity and is applicable to both small- and large-scale production of oligonucleotides such as siRNAs and aptamers. The patent further expands Sirna's leadership position in the area of synthesis and manufacturing of GMP quality RNA which is required for both chemically modified and unmodified siRNA-based therapeutics.

Sirna now holds 48 issued patents with an additional 240 plus patent applications still pending.

In order to manufacture siRNA it takes a synthesis protocol encompassing some 150 steps. This newly issued patent covers the required steps to manufacture siRNA material that achieves not only yields in excess of 60% but of unparalleled quality too.