Ligand announces results from melphalan Phase II study on multiple myeloma

Ligand Pharmaceuticals Incorporated (NASDAQ: LGND) announced that results from the Phase II study of its Captisol-enabled, propylene glycol-free (PG-free) Melphalan program were featured this evening in a poster presentation at the combined annual meetings of the Center for International Blood & Marrow Transplant Research (CIBMTR) and the American Society for Blood and Marrow Transplantation (ASBMT) in San Diego.

The Phase II study was completed in late 2011 and compared the safety, tolerability and pharmacokinetic profiles of the PG-free Melphalan intravenous formulation and the current clinically-used intravenous formulation of melphalan (sold by GlaxoSmithKline as Alkeran^® for Injection) for multiple myeloma patients undergoing autologous transplantation. The Captisol-enabled product is expected to allow for longer administration durations and slower infusion rates, potentially enabling clinicians to safely achieve a higher dose intensity of pre-transplant chemotherapy, which may lead to better therapeutic outcomes.

The key findings and new data presented include:

• The Phase II study successfully met all endpoints.
• The new PG-free Melphalan was bioequivalent to Alkeran per guidance requirements, while also demonstrating a marginally higher systemic drug exposure (112%).
• 37.5% (9 of 24) of the multiple myeloma patients treated in the study were at Stage 2 at study entry and 62.5% (15 of 24) were at Stage 3 at study entry.
• PG-free Melphalan, administered as half of a high-dose conditioning regimen, clearly resulted in successful myeloablation (100% of patients) and subsequent engraftment (100% of patients) with no additional toxicity.
• Based on the successful Phase II results, the follow-on Pivotal study will utilize a dosing regimen comparable to Alkeran. The Pivotal study is designed to expose patients exclusively to the PG-free Melphalan formulation and will further elaborate the safety and efficacy measures for the product.

The full poster presentation can be viewed by visiting the Investor Relations section of Ligand's Web site at www.ligand.com.

Dr. Omar Aljitawi from the University of Kansas Medical Center stated: "This study clearly proves that Captisol-enabled PG-free Melphalan is bioequivalent to Alkeran. Additionally, the higher systemic levels seen with the Captisol-enabled product might result in better disease control, an end-point that will be examined in the follow-on Pivotal trial. Furthermore, this study should encourage investigators to study this formulation for indications where the presence of PG also creates issues and where extended infusion times are desirable."

"We are very pleased to present this positive Phase II data at the BMT Tandem meeting. Transplant is and will remain a key element of managing multiple myeloma, and Ligand's Captisol-enabled PG-free formulation has the potential to revolutionize the use of melphalan in this setting," said Matthew W. Foehr, Chief Operating Officer of Ligand Pharmaceuticals. "This program's clear development path, with an established Orphan designation and a single remaining Pivotal trial make it a highly valuable asset in our broad portfolio. We continue to examine the partnering landscape for this program while our R&D team prepares to initiate the Pivotal trial this year."