ISIS Pharmaceuticals Initiates a Clinical Study of ISIS-SMN Rx in Infants With Spinal Muscular Atrophy

CARLSBAD, Calif., April 23, 2013 /PRNewswire/ -- Isis Pharmaceuticals, Inc. (NASDAQ: ISIS) announced the initiation of a Phase 2 study of ISIS-SMN_Rx in infants with spinal muscular atrophy (SMA).   SMA is a severe and rare genetic neuromuscular disease characterized by muscle atrophy and weakness and is the most common genetic cause of infant mortality.  The study, which will begin enrolling patients soon, is a Phase 2 study in eight patients with infantile-onset SMA. The study, which initiates the Phase 2/3 program for ISIS-SMN_Rx in infants, is designed to provide data to allow Isis to define the optimal dose for the larger planned Phase 2/3 study in infants and to provide safety and tolerability data.  Isis will earn a $3.5 million milestone payment from Biogen Idec when the first infant is dosed in the study, which is projected for May 2013.  

The Phase 2 study of ISIS-SMN_Rx is an open-label, multiple-dose, dose-escalation pilot study, which will include eight infants who have been diagnosed with SMA.  To meet enrollment criteria, infants must be between the ages of three weeks and seven months, live in close proximity to a study site and pass screening evaluations conducted at study sites.  The study will be conducted at centers in the United States and Canada.  For further study information, please visit www.clinicaltrials.gov and search for ISIS-SMN_Rx. 

"We are very pleased with the progress Isis has made in advancing this new potential therapeutic agent, which could fill the therapeutic void for SMA and transform the hopes and futures of patients and families with this devastating disease.  It is a testament to the commitment of Isis that, in just a few years, this program has moved rapidly from research to late-stage clinical development.  We look forward to continuing to support the SMA community with the goal of accelerating a treatment for children with SMA," said Karen S. Chen, Ph.D., chief scientific officer at the SMA Foundation.

"We are very pleased with the achievement of this clinical milestone of advancing a potentially disease-modifying drug treatment into later-stage clinical trials.  This achievement is a culmination of the close interactions between basic researchers, families, clinicians and industry.  Families of SMA applauds Isis for investing in and leading drug development efforts for this devastating, orphan disease," said Jill Jarecki, Ph.D., research director of Families of SMA.

Isis completed an open-label Phase 1 study evaluating ISIS-SMN_Rx in children (age 2 and older) with SMA, in which ISIS-SMN_Rx was well tolerated at all dose levels when administered intrathecally as a single dose directly into the spinal fluid. Although the study was not designed to provide evidence of functional activity improvements in the Hammersmith Functional Motor Scale-Expanded, a measure of muscle function, were observed in a number of these children.  In addition to the infant pilot study, Isis is also completing a multiple-dose, dose-escalation Phase 1b/2a study of ISIS-SMN_Rx in children with SMA.  Data from the Phase 1b/2a study will provide information to determine the dose for the Phase 2/3 registration-directed study in children (age 2 and older) with SMA.

"SMA represents a serious unmet medical need with no currently available treatments. Based on its mechanism of action and encouraging preclinical and clinical data, ISIS-SMN_Rx could be an effective treatment for these very sick children, though additional work still needs to be done.  The rapid advancement of this drug to this stage in development reflects the support from the SMA community and the success of the collaboration between Isis and Biogen Idec.  Isis and Biogen Idec are committed to advancing the program for children with SMA," said C. Frank Bennett, Ph.D., senior vice president of research at Isis.  "ISIS-SMN_Rx is our first drug designed to intervene in the splicing of RNA to increase the production of a normal protein, SMN.  Antisense drugs could offer novel new therapeutics for a number of severe neurodegenerative diseases.  The encouraging safety data from this program and our preclinical and clinical experience in other neurodegenerative diseases support the broadening of our efforts to develop antisense drugs to treat such diseases."

ABOUT SMA
SMA is a severe genetic disease that affects approximately 30,000-35,000 patients in the United States, Europe and Japan. SMA is caused by a loss of, or defect in, the survival motor neuron 1 (SMN1) gene leading to a decrease in the survival motor neuron (SMN) protein. SMN is critical to the health and survival of nerve cells in the spinal cord responsible for neuromuscular growth and function. One in 50 people, the equivalent of about 6 million people in the United States, are carriers of a defective SMN1 gene, which is unable to produce fully functional SMN protein. Carriers experience no symptoms and do not develop the disease. However, when both parents are carriers, there is a one in four chance that their child will have SMA. The severity of SMA correlates with the amount of SMN protein. Infants with Type I SMA, the most severe form of the disease, produce very little SMN protein and have a life expectancy of less than two years. Children with Type II have greater amounts of SMN protein but still have a shortened lifespan and are never able to stand independently. Children with Type III have a normal lifespan but accumulate life-long physical disabilities as they grow.

ABOUT ISIS-SMN_Rx
ISIS-SMN_Rx is designed to alter the splicing of a closely related gene (SMN2) to increase production of fully functional SMN protein.  The United States Food and Drug Administration granted orphan drug status and fast track designation to ISIS-SMN_Rx for the treatment of patients with SMA.  Isis is currently in collaboration with Biogen Idec to develop and potentially commercialize the investigational compound, ISIS-SMN_Rx, to treat all types of SMA.  Under the terms of the January 2012 agreement, Isis is responsible for global development and Biogen Idec has the option to license the compound until completion of the first successful Phase 2/3 study.  ISIS-SMN_Rx is currently being evaluated in a Phase 1b/2a multiple-dose, dose-escalation study in children with SMA.  In this study, children will either receive two or three doses of ISIS-SMN_Rx over the course of the study. 

Isis acknowledges support from the following organizations for ISIS-SMN_Rx: Muscular Dystrophy Association, SMA Foundation, Families of SMA and intellectual property licensed from Cold Spring Harbor Laboratory and the University of Massachusetts Medical School.

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, severe and rare diseases, and cancer.  Isis' partner, Genzyme, is commercializing Isis' lead product, KYNAMRO™, in the United States for the treatment of patients with HoFH.  Genzyme is also pursuing marketing approval of KYNAMRO in other markets.  Isis' patents provide strong and extensive protection for its drugs and technology.  Additional information about Isis is available at www.isispharm.com.

ISIS PHARMACEUTICALS' FORWARD-LOOKING STATEMENT
This press release includes forward-looking statements regarding Isis' strategic alliance with Biogen Idec, and the discovery, development, activity, therapeutic and commercial potential and safety of ISIS-SMN_Rx.  Any statement describing Isis' goals, expectations, financial or other projections, intentions or beliefs, including the commercial potential of KYNAMRO, 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, 2012, which is on file with the SEC. Copies of this 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.

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

SOURCE Isis Pharmaceuticals, Inc.