Human Genome Calls Second Lupus Drug Study a Success

ROCKVILLE, Md. (TheStreet) -- Human Genome Sciences(HGSI Quote) announced positive results Monday from a second pivotal study of its experimental lupus drug Benlysta, although the drug did not perform as well as it did in the first study.

Still, the company along with partner GlaxoSmithKline(GSK Quote) said they plan to seek regulatory approval for Benlysta in the U.S. and Europe during the first half of next year. If approved, Benlysta will become the first new lupus drug to reach the market in more than four decades.

Regulators require two positive clinical trials of a lupus drug for approval, so investors have waited nervously for Monday's results from the so-called Bliss-76 study of Benlysta ever since the positive data from the first study -- Bliss-52 -- were released in July.

July's trial was a unambiguous success, Bliss-76 less so. Human Genome reported Monday that 43.2% of lupus patients responded to treatment with a high dose of Benlysta after one year compared to 33.8% of patients treated with a placebo -- a difference that was statistically significant for the trial's primary endpoint.

However, a lower dose of Benlysta only benefited 40.6% of lupus patients after one year and that difference was not statistically significant compared to placebo.

In the first Bliss-52 trial, patients treated with both the high and low doses of Benlysta achieved a statistically significant response over placebo.

Likewise, mixed results were also reported from the study's key secondary endpoint. The high dose of Benlysta demonstrated a statistically significant decrease versus placebo in a scale of lupus disease activity, but the low dose did not.