Recently, Human Genome Sciences, Inc. (HGSI) announced that its potential blockbuster lupus drug candidate Benlysta (belimumab) failed to meet its secondary goals in a late-stage trial BLISS-76.

Human Genome and GlaxoSmithKline plc (GSK) are co-developing Benlysta for treating patients suffering from systemic lupus erythematosus (SLE). Lupus, an inflammatory disease, causes the body’s immune system to attack its own tissues and organs. Benlysta, a human monoclonal antibody, is designed to suppress the body’s immune response to lupus.

BLISS-76 is the second of two pivotal phase III trials in patients with active SLE. The double-blind, placebo-controlled, multi-center trial evaluated the efficacy and safety of Benlysta plus standard of care compared to placebo plus standard of care for treating SLE patients.

The study revealed that at Week 76 Benlysta plus standard of care showed higher response rates compared with placebo plus standard of care. However, this secondary endpoint did not meet statistical significance thereby showing that Benlysta was no way more effective than standard treatment after one and a half years time.

Even though Benlysta did not prove to be more effective than placebo in the long-term, it met the primary end-point in BLISS-76 through 52 weeks in Nov 2009. Furthermore, positive results from the first trial, BLISS-52, were announced in the third quarter of 2009.

Based on these positive results, the company intends to seek marketing approval for Benlysta during the second quarter of 2010 in the United States and Europe, notwithstanding the disappointing long-term data. However, we believe that disappointing long-term data might come in the way of the candidate getting approved.

Benlysta, if approved, would be the first new lupus drug to hit the market in 50 years. Lupus affects about 1.5 million people in the United States and 5 million people worldwide.

Currently, we are Neutral on Human Genome Sciences.

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