Press Releases

Ligand Partner GlaxoSmithKline Receives FDA Acceptance and Granted Priority Review for PROMACTA(R) NDA

SAN DIEGO--

Ligand Pharmaceuticals Incorporated (NASDAQ:LGND) today announced that the U.S. Food and Drug Administration (FDA) has accepted for filing and review GlaxoSmithKline's new drug application (NDA) and has granted a priority review status for PROMACTA(R) (eltrombopag) for treatment of chronic short-term idiopathic thrombocytopenic purpura (ITP). Priority review is granted by the FDA for a treatment that addresses significant unmet medical needs or has the potential to provide a significant improvement compared to marketed products, and results in a review period of six months from the date of NDA submission.

If approved, PROMACTA would be the first oral thrombopoietin receptor agonist therapy for the short-term treatment of previously treated patients with chronic ITP to increase platelet counts and reduce or prevent bleeding. Chronic ITP is a disorder marked by increased platelet destruction and/or inadequate platelet production in the blood, which causes an increased risk of bruising and bleeding. PROMACTA is an investigational, once-daily oral treatment that induces the proliferation and differentiation of cells in the bone marrow to produce platelets.

"Priority FDA review for PROMACTA clearly reflects the need for an effective therapy for patients suffering from ITP," said John L. Higgins, President and Chief Executive Officer of Ligand Pharmaceuticals. "We are extremely pleased and commend GlaxoSmithKline's team for their progress and dedication in taking PROMACTA a step closer toward commercialization. This is a critical milestone and we look forward to the completion of the FDA's review."

Ligand and GlaxoSmithKline Collaboration

The GSK-Ligand collaboration began in 1997 to utilize Ligand's expertise and technology to discover small-molecule drugs to control hematopoieses and treat patients with cancer, anemia or platelet deficiencies. The research phase of the collaboration ended in 2001. GSK is responsible for the registration and worldwide marketing of PROMACTA.

About Ligand Pharmaceuticals

Ligand discovers and develops new drugs that address critical unmet medical needs of patients in the areas of thrombocytopenia, cancer, hepatitis C, hormone-related diseases, osteoporosis and inflammatory diseases. Ligand's proprietary drug discovery and development programs are based on its leadership position in gene transcription technology, primarily related to intracellular receptors.

Forward-Looking Statements

This news release contains 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 future action by the FDA for the recently submitted NDA; the promise of PROMACTA (eltrombopag) future regulatory approvals; increases in shareholder value; and future milestone and royalty payments. Actual events or results may differ from our expectations. There can be no assurance GlaxoSmithKline, or any of our other partners will continue clinical development of any compound(s); that clinical development will be successful; that future clinical trial data will be favorable or that such trials will confirm any improvements over other products or lack of negative impacts; that drugs will receive required regulatory approvals or that they will be commercially successful therapies, provide new options or be successfully marketed; that our partner portfolio will continue to mature, that our business will continue to grow or that shareholder value will increase, that the FDA will accept any filing, that any future milestone or royalty payments will be received, or that if any future milestones or royalties are received that they won't be subject to sharing obligations with Rockefeller University and/or any other third party. Our stock price could be harmed if any of these events or trends fails to occur, is delayed or otherwise differs from expectations. Additional information concerning these and other risk factors affecting Ligand's business can be found on the company's prior press releases as well as in public periodic filings with the Securities and Exchange Commission, available via www.ligand.com. 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.

Source: Ligand Pharmaceuticals Incorporated