Ligand Partner GSK Receives Marketing Authorization from the European Commission for Additional Revolade™ (Eltrombopag)

  Ligand Partner GSK Receives Marketing Authorization from the European
  Commission for Additional Revolade™ (Eltrombopag) Indication as the First
  Approved Treatment for Chronic Hepatitis C-Associated Thrombocytopenia

Business Wire

SAN DIEGO -- September 24, 2013

Ligand Pharmaceuticals Incorporated (NASDAQ: LGND) partner GlaxoSmithKline plc
(LSE:GSK) (NYSE:GSK) announced today that the European Commission has granted
an additional indication for Revolade™ (eltrombopag) as a treatment for low
platelet counts (thrombocytopenia) in adult patients with chronic hepatitis C
infection, where the degree of thrombocytopenia is the main factor preventing
the initiation or limiting the ability to maintain optimal interferon
(IFN)-based therapy.^1

Thrombocytopenia may prevent the initiation^2 and maintenance of peginterferon
(pIFN)-based treatment, thereby reducing a patient’s chances of achieving a
sustained virologic response (SVR)*^3 - the primary goal of hepatitis C
treatment.

“We are extremely pleased with the decision of the European Commission, and
eagerly await the launch of Revolade in the European Union for this
indication. This is an important achievement, as otherwise very sick patients
suffering with chronic hepatitis C infection with few therapeutic options will
now have the opportunity to potentially receive needed treatment,” commented
John Higgins, President and Chief Executive Officer of Ligand. “Ligand
commends GSK’s global Revolade and Promacta team for their commitment to this
program and for leading it to continued regulatory success.”

About Eltrombopag

Eltrombopag, marketed under the brand name Revolade™ in Europe and most ex-US
countries, and Promacta® in the U.S., is an oral thrombopoietin receptor
agonist licensed in over 90 countries around the world as a treatment for
thrombocytopenia in adult patients with chronic immune (idiopathic)
thrombocytopenic purpura (ITP).

Eltrombopag, indicated in adult patients as a once-daily oral therapy, was
approved for chronic hepatitis C-associated thrombocytopenia by the European
Commission on September 23, 2013. Promacta®/Revolade™ is approved for chronic
hepatitis C associated thrombocytopenia in Argentina, Australia, Bangladesh,
Pakistan, Philippines and the US.

About GlaxoSmithKline

GlaxoSmithKline - one of the world’s leading research-based pharmaceutical and
healthcare companies – is committed to improving the quality of human life by
enabling people to do more, feel better and live longer. For further
information please visit www.gsk.com.

About Ligand Pharmaceuticals

Ligand is a biopharmaceutical company that develops and acquires assets it
believes will generate royalty revenues and, under its lean corporate cost
structure, produce sustainable profitability. Ligand has a diverse asset
portfolio addressing the unmet medical needs of patients for a broad spectrum
of diseases including thrombocytopenia, multiple myeloma, diabetes, hepatitis,
muscle wasting, dyslipidemia, anemia and osteoporosis. Ligand’s Captisol
platform technology is a patent-protected, chemically modified cyclodextrin
with a structure designed to optimize the solubility and stability of drugs.
Ligand has established multiple alliances with the world’s leading
pharmaceutical companies including GlaxoSmithKline, Onyx Pharmaceuticals,
Merck, Pfizer, Baxter International, Bristol-Myers Squibb, Lundbeck Inc., Eli
Lilly & Co. and Spectrum Pharmaceuticals. Please visit www.captisol.com for
more information on Captisol and www.ligand.com for more information on
Ligand.

Follow Ligand on Twitter @Ligand_LGND.

Forward-Looking Statements

This news release contains certain forward-looking statements by Ligand that
involve risks and uncertainties and reflect Ligand’s judgment as of the date
of this release. These statements include those related to the importance of
the approval of additional indications for Revolade (eltrombopag) or any
potential launch or marketing effort associated therewith. Actual events or
results may differ from Ligand’s expectations. There can be no assurance
GlaxoSmithKline will continue clinical development of eltrombopag, or any
additional indications thereof, that the product will be commercially
successful, provide new options or be successfully marketed; that any future
milestone or royalty payments will be received, or that if any future
milestones or royalties are received that they will not be subject to sharing
obligations with any third party. The failure to meet expectations with
respect to any of the foregoing matters may reduce Ligand’s stock price.
Additional information concerning these and other risk factors affecting
Ligand’s business can be found in prior press releases available via
www.ligand.com as well as in Ligand’s public periodic filings with the
Securities and Exchange Commission at www.sec.gov. Ligand disclaims any intent
or obligation to update these forward-looking statements beyond the date of
this release. This caution is made under the safe harbor provisions of the
Private Securities Litigation Reform Act of 1995.

^1 REVOLADE™ Summary of Product Characteristics.

^2 Giannini EG et al. Liver Int 2012;32(6):1113-1119.

^3 Everson GT et al. Hepatol 2006;44:1675-1684.

* where the hepatitis C virus remains undetectable for six months – following
completion of antiviral therapy

Contact:

Ligand Pharmaceuticals Incorporated
John Higgins, President and CEO
Jennifer Capuzelo
(858) 550-7584
jcapuzelo@ligand.com
or
LHA
Don Markley
(310) 691-7100
dmarkley@lhai.com