Isis Pharmaceuticals Earns $2 Million from GSK for the Advancement of ISIS-TTR Rx

Isis Pharmaceuticals Earns $2 Million from GSK for the Advancement of ISIS-TTR
                                      Rx

PR Newswire

CARLSBAD, Calif., July 30, 2013

CARLSBAD, Calif., July 30, 2013 /PRNewswire/ --Isis Pharmaceuticals, Inc.
(NASDAQ: ISIS) announced today that it has earned a $2 million milestone
payment from GlaxoSmithKline (NYSE: GSK) related to the advancement of the
ongoing Phase 2/3 study of ISIS-TTR[Rx] in patients with familial amyloid
polyneuropathy (FAP).

ISIS-TTR[Rx] is an antisense drug in development with GSK for the treatment of
transthyretin amyloidosis, a severe and rare genetic disease characterized by
progressive dysfunction of peripheral nerve and/or heart tissues. Isis has
earned $20 million in upfront and milestone payments prior to first patient
dosed in the ongoing Phase 2/3 study. The $2 million milestone payment
announced today is the first milestone of the $50 million in milestone
payments Isis is eligible to earn as the Phase 2/3 study progresses. In
addition, if GSK elects to exercise its option to exclusively license the
ISIS-TTR[Rx ]program, Isis is eligible to receive a license fee, regulatory
and sales milestone payments and double-digit royalties on sales of
ISIS-TTR[Rx].

The Phase 2/3 study of ISIS-TTR[Rx] is a randomized, double-blind,
placebo-controlled, international study designed to support an application for
marketing approval of ISIS-TTR[Rx] in patients with FAP. The fifteen month
study will measure the effects of ISIS-TTR[Rx ]on neurological dysfunction and
on quality-of-life. For further study information, please visit
www.clinicaltrials.gov and search for the identifier number NCT01737398.

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 GlaxoSmithKline, and the discovery, development,
activity, therapeutic and commercial potential and safety of ISIS-TTR[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 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.

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

SOURCE Isis Pharmaceuticals, Inc.

Website: http://www.isispharm.com
Contact: D. Wade Walke, Ph.D. Executive Director, Corporate Communications and
Investor Relations, 760-603-2741; Amy Blackley, Ph.D., Associate Director,
Corporate Communications, 760-603-2772