Human Genome Sciences and GSK’s Lupus Candidate Hits the Mark in Second Phase III Trial

Human Genome Sciences (HGS) and GlaxoSmithKline confirmed that their systemic lupus erythematosus (SLE) drug candidate, Benlysta™, met its primary endpoint in the second (Bliss-76) of two Phase III trials. HGS’ stock jumped almost 33% from $18.69 at closing on Friday to open today at $24.83.

Positive results from the first Phase III trial, Bliss-52, were reported in July. In the first day of trading after announcing Bliss-52 data, the firm’s value quadrupled to reach $12.51. HGS and GSK say that they plan to submit marketing authorizations for Benlysta in the U.S., Europe, and other regions during the first half of 2010.

Bliss-76 is an ongoing study evaluating the treatment of SLE using either different doses of Benlysta plus standard of care or placebo plus standard of care. Data at 52 weeks showed that in comparison with placebo, adding Benlysta to standard of care resulted in statistically significant improvements in the SLE Responder Index. The trial will continue for an additional 24 weeks.

Benlysta is a human mAb-based drug that inhibits B-lymphocyte stimulator (BLys), a target HGS discovered in 1997. The company claims that Benlysta acts by specifically recognizing and binding to BLyS, inhibiting BLyS-related stimulation of B-cell development, and restoring the potential for autoantibody-producing B cells to undergo the normal process of apoptosis.

The drug is being by developed by HGS and GSK in SLE and other autoimmune diseases under a co-development and commercialization agreement signed in August 2006. The companies will share equally in Phase III/IV development costs, sales and marketing expenses, as well as profits of any product commercialized under the agreement.