Isis Updates KYNAMRO Submission Timeline

Genzyme plans to submit in the first quarter of 2012

CARLSBAD, Calif., Dec. 15, 2011 /PRNewswire/ -- Isis Pharmaceuticals, Inc. (NASDAQ: ISIS) announced today that there will be a slight delay in the submission of the new drug application (NDA) to the United States Food and Drug Administration for KYNAMRO™(mipomersen sodium).  This additional time will allow Genzyme to complete preparation of additional technical documentation. The submission of the U.S. NDA seeking approval of KYNAMRO for the treatment of homozygous familial hypercholesterolemia (FH) is now planned for the first quarter of 2012.

In July of this year, Genzyme and Isis submitted a marketing authorization application to the European Medicines Agency seeking approval for KYNAMRO for the treatment of patients with homozygous and severe heterozygous FH.

About KYNAMRO (mipomersen sodium)

KYNAMRO is a first-in-class apo-B synthesis inhibitor currently in late-stage development for the reduction of LDL cholesterol (LDL-C).  It is intended to reduce LDL-C by preventing the formation of atherogenic lipoproteins, the particles that carry cholesterol through the bloodstream.  KYNAMRO acts by blocking the production of apolipoprotein B (apoB), the protein that provides the structural core for these atherogenic particles, including LDL and lipoprotein-a (Lp(a)).

About Familial Hypercholesterolemia

FH is a genetic disease that results in elevated LDL-C levels and family patterns of increased risk of premature heart disease and heart disease-related death.  FH patients have inherited abnormalities in liver cells that are responsible for clearing LDL particles from the blood.  FH is autosomal dominant, which means that all first-degree relatives of FH patients have a 50 percent chance of having the disease as well, making early detection through family screening critically important. 

The most severe FH patients have LDL-C levels that are two to four times higher than recommended levels, even when taking multiple cholesterol-lowering medications.  These people, who are characterized as having severe FH, include: those who have inherited the disease from both parents (homozygous FH (HoFH)) and those who have inherited it from only one parent, and have a severe form of the disease (severe heterozygous FH (severe HeFH)).

About Isis Pharmaceuticals, Inc.

Isis is exploiting its leadership position in antisense technology to discover and develop novel drugs for its product pipeline and for its partners.  Isis' broad pipeline consists of 28 drugs to treat a wide variety of diseases with an emphasis on cardiovascular, metabolic and severe and rare/neurodegenerative diseases, and cancer.  Isis' partner, Genzyme, plans to commercialize Isis' lead product, mipomersen, following regulatory approval, which is expected in 2012.  Isis' patents provide strong and extensive protection for its drugs and technology.  Additional information about Isis is available at www.isispharm.com.

Forward Looking Statement

This press release includes forward-looking statements regarding Isis' collaboration with Genzyme, a Sanofi company, the planned NDA filing for mipomersen and the development, activity, therapeutic and safety of mipomersen in treating patients with high cholesterol.  Any statement describing Isis' goals, expectations, financial or other projections, intentions or beliefs, including the planned commercialization of mipomersen is a forward-looking statement and should be considered an at-risk statement.  Such statements are subject to certain risks and uncertainties, particularly those inherent in the process of discovering, developing and commercializing drugs that are safe and effective for use as human therapeutics, and in the endeavor of building a business around such drugs.  Isis' forward-looking statements also involve assumptions that, if they never materialize or prove correct, could cause its results to differ materially from those expressed or implied by such forward-looking statements.  Although Isis' forward-looking statements reflect the good faith judgment of its management, these statements are based only on facts and factors currently known by Isis.  As a result, you are cautioned not to rely on these forward-looking statements.  These and other risks concerning Isis' programs are described in additional detail in Isis' annual report on Form 10-K for the year ended December 31, 2010 and its most recent quarterly report on Form 10-Q, which are on file with the SEC. Copies of these and other documents are available from the Company.

In this press release, unless the context requires otherwise, "Isis," "Company," "we," "our," and "us" refers to Isis Pharmaceuticals and its subsidiaries, including Regulus Therapeutics Inc., its jointly owned subsidiary.

Isis Pharmaceuticals® is a registered trademark of Isis Pharmaceuticals, Inc.  KYNAMRO™ is a trademark of Genzyme Corporation.

SOURCE Isis Pharmaceuticals, Inc.