Salix and Progenics Announce FDA Advisory Committee to Review Relistor sNDA for Opioid-Induced Constipation in Patients with

  Salix and Progenics Announce FDA Advisory Committee to Review Relistor sNDA
  for Opioid-Induced Constipation in Patients with Chronic Pain

Business Wire

RALEIGH, N.C. & TARRYTOWN, N.Y. -- June 11, 2013

Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP) and Progenics Pharmaceuticals
(NASDAQ:PGNX) today announced that the FDA is seeking input from an Advisory
Committee on Salix's Supplemental New Drug Application (sNDA) for RELISTOR^®
(methylnaltrexone bromide) Subcutaneous Injection, for opioid-induced
constipation, or OIC, in patients with chronic pain.

The FDA's action to convene an Advisory Committee was taken in response to the
formal appeal by Salix of the complete response action taken by the FDA on
July 27, 2012 regarding the RELISTOR sNDA for chronic pain. The FDA has said
that it will take action under the appeal after receiving input from the
Advisory Committee. The FDA will notify the Company once the Advisory
Committee meeting date has been determined.

“We remain optimistic that with the FDA and guidance from the Advisory
Committee, we can find a path forward that will get this new and alternative
therapy to patients with opioid-induced constipation who are taking opioids
for their chronic pain," stated Bill Forbes, PharmD, Executive Vice President,
Medical, Research and Development and Chief Development Officer, Salix. “We
look forward to the opportunity to bring Relistor to this Advisory Committee
to openly discuss our proposed indication for the use of Relistor in patients
suffering from OIC and chronic pain. We understand from an FDA communication
that the FDA will seek advice from pain, gastrointestinal, safety and
cardiovascular experts. We believe that some of the areas being considered for
discussion during this meeting will include: 1) the potential for drugs in
this class to causewithdrawal symptoms, 2) the strength of a potential
cardiovascular signal seen with another drug in this class of drugs and the
available safety data with Relistor in regards to a potential CV signal as
well as 3) the need and timing (pre-approval vs. post-approval) of MACE
studies with drugs of this class. While it is not possible to definitively
determine the duration of the appeal process, at this time, we continue to
believe a conclusion could be reached during 2013. Relistor has been available
to patients with advanced illness who suffer from OIC since 2008.”

The FDA has communicated that it is convening the Advisory Committee for the
following reasons:

  *“The potential cardiovascular safety signal observed in the 12-month
    safety trial of another peripheral mu-opioid antagonist for the treatment
    of opioid-induced constipation in patients with chronic non-cancer pain
    raises concern for this class of drug products.”
  *The RELISTOR “supplemental application contains only uncontrolled
    long-term safety data, and while there is no cardiovascular signal
    apparent in this data, the lack of a control population does not allow a
    definitive evaluation to be made to rule out a potential cardiovascular
    safety signal.”
  *“FDA needs to provide consistent advice regarding the need for Major
    Adverse Cardiovascular Event (MACE) studies to applicants developing drug
    products in this class for this indication. For this reason, a broader
    discussion of the potential for cardiovascular events across the drug
    class is necessary.”

About Opioids, Constipation and RELISTOR (methylnaltrexone bromide)

Opioid analgesics are frequently prescribed for patients with chronic pain.
Constipation, a common side effect, occurs in patients receiving opioid
therapy. RELISTOR is the first approved medication that specifically targets
the underlying cause of opioid-induced constipation in patients with advanced
illness receiving palliative care when response to laxative therapy has not
been sufficient. Opioids relieve pain by specifically interacting with
mu–opioid receptors within the brain and spinal cord. However, opioids also
interact with mu–opioid receptors found outside the central nervous system,
such as those within the gastrointestinal tract, resulting in constipation
that can be debilitating. RELISTOR is a peripherally acting mu–opioid receptor
antagonist that does not cross the blood-brain barrier and was specifically
designed to block mu-opioid receptors in the GI tract, therefore decreasing
the constipating effects of opioid pain medications without affecting their
ability to relieve pain.

RELISTOR Subcutaneous Injection was approved in the United States in 2008 for
the treatment of opioid-induced constipation in patients with advanced illness
who are receiving palliative care, when response to laxative therapy has not
been sufficient. The use of RELISTOR beyond four months has not been studied.
The drug is also approved for use in 58 countries worldwide, including the
European Union, Canada, and Australia. In the 27 member states of the E.U., as
well as Iceland, Norway and Liechtenstein, RELISTOR is approved for the
treatment of opioid–induced constipation in advanced illness patients who are
receiving palliative care when response to usual laxative therapy has not been
sufficient. In Canada, the drug is approved for the treatment of
opioid–induced constipation in patients with advanced illness, receiving
palliative care. When response to laxatives has been insufficient, RELISTOR
should be used as an adjunct therapy to induce a prompt bowel movement.
Applications in additional countries are pending. RELISTOR is under license to
Salix Pharmaceuticals and Ono Pharmaceutical from Progenics Pharmaceuticals.

For more information about RELISTOR, please visitwww.RELISTOR.com

Important Safety Information about RELISTOR

RELISTOR^® (methylnaltrexone bromide) Subcutaneous Injection is
contraindicated in patients with known or suspected mechanical
gastrointestinal obstruction.

If severe or persistent diarrhea occurs during treatment, advise patients to
discontinue therapy with RELISTOR and consult their physician.

Rare cases of gastrointestinal (GI) perforation have been reported in advanced
illness patients with conditions that may be associated with localized or
diffuse reduction of structural integrity in the wall of the GI tract (i.e.,
cancer, peptic ulcer, Ogilvie's syndrome). Perforations have involved varying
regions of the GI tract (e.g., stomach, duodenum, colon). Use RELISTOR with
caution in patients with known or suspected lesions of the GI tract. Advise
patients to discontinue therapy with RELISTOR and promptly notify their
physician if they develop severe, persistent, and/or worsening abdominal
symptoms.

Use of RELISTOR has not been studied in patients with peritoneal catheters.

Use of RELISTOR beyond four months has not been studied.

Safety and efficacy of RELISTOR have not been established in pediatric
patients.

The most common adverse reactions reported with RELISTOR compared with placebo
in clinical trials were abdominal pain (28.5%), flatulence (13.3%), nausea
(11.5%), dizziness (7.3%), diarrhea (5.5%), and hyperhidrosis (6.7%).

Please see complete Prescribing Information for RELISTOR.

About Salix

Salix Pharmaceuticals, Ltd., headquartered in Raleigh, North Carolina,
develops and markets prescription products for the prevention and treatment of
gastrointestinal diseases. Salix’s strategy is to in-license late-stage or
marketed proprietary therapeutic products, complete any required development
and regulatory submission of these products, and market them through the
Company’s gastroenterology specialty sales and marketing team.

Salix trades on the NASDAQ Global Select Market under the ticker symbol
“SLXP”.

For more information, please visit our Website at www.salix.com or contact the
Company at 919-862-1000. Follow us on Twitter (@SalixPharma) and Facebook
(www.facebook.com/SalixPharma). Information on our Twitter feed, Facebook page
and web site is not incorporated in our SEC filings.

About Progenics

Progenics Pharmaceuticals, Inc. of Tarrytown, N.Y. is a biopharmaceutical
company dedicated to developing innovative medicines to treat disease, with a
focus on cancer and related conditions. Progenics’ pipeline candidates include
PSMA ADC, a human monoclonal antibody-drug conjugate in phase 1 testing for
treatment of prostate cancer, and preclinical stage novel multiplex
phosphoinositide 3-kinase (PI3K) inhibitors for the treatment of cancer.
Progenics has exclusively licensed development and commercialization rights
for its first commercial product, Relistor^®, to Salix Pharmaceuticals, Ltd.
for markets worldwide other than Japan, where Ono Pharmaceutical Co., Ltd.
holds an exclusive license for the subcutaneous formulation. Relistor
(methylnaltrexone bromide) subcutaneous injection is a first-in-class
treatment for opioid-induced constipation approved in more than 50 countries
for patients with advanced illness.

Please Note: The materials provided herein that are not historical facts are
or might constitute forward-looking statements under the safe harbor
provisions of the Private Securities Litigation Reform Act of 1995. Although
we believe the expectations reflected in such forward-looking statements are
based on reasonable assumptions, our expectations might not be attained.
Forward-looking statements involve known and unknown risks that could cause
actual results to differ materially from expected results. Factors that could
cause actual results to differ materially from our expectations expressed in
the report include, among others: the unpredictability of the duration and
results of regulatory review of New Drug Applications and Investigational New
Drug Applications, including specifically results of appeals and Advisory
Committees; the high cost and uncertainty of the research, clinical trials and
other development activities involving pharmaceutical products; the possible
impairment of, or inability to obtain intellectual property rights and the
costs of obtaining such rights from third parties in an increasingly global
market; our dependence on our first seven pharmaceutical products,
particularly Xifaxan and Relistor, and the uncertainty of market acceptance of
our products intense competition, including from generics in an increasingly
global market; general economic conditions; our need to maintain
profitability; the uncertainty of obtaining, and our dependence on, third
parties to manufacture and sell our products; results of ongoing and any
future litigation and investigations and other risk factors detailed from time
to time in our other SEC filings.

Contact:

Salix
Adam C. Derbyshire, 919-862-1000
Executive Vice President and Chief Financial Officer
or
G. Michael Freeman, 919-862-1000
Associate Vice President, Investor Relations and Corporate Communications
or
Progenics Contact:
Kathleen Frederiksen, 914-789-2871
Director, Corporate Development