Shares of Human Genome Sciences soared following the Rockville biotech's announcement last week that its lupus drug yielded positive results in the second of two pivotal phase 3 clinical trials.
It was the second time since July that HGS reported strong results from a phase 3 trial of belimumab, which HGS is developing with British pharma giant GlaxoSmithKline under the brand name Benlysta.
Based on these results, HGS plans to seek approval next year from the federal Food and Drug Administration and European regulators to market Benlysta, which would be the first FDA-approved drug for lupus in 50 years, according to the company. Pending those approvals, the drug could hit the market in the U.S. in about a year and a few months later in Europe, Barry A. Labinger, executive vice president and chief commercial officer, said in a conference call with analysts and investors.
Following the announcement, HGS shares rose 35.3 percent in trading on the Nasdaq exchange and rose a bit more during the week.
When compared with a placebo plus standard of care, Benlysta plus standard of care met its primary goal of a "statistically significant improvement in patient response," the company said in a statement. The drug was also generally well-tolerated.
The trial, called BLISS-76, is scheduled to run for 24 more weeks, for a total of 76 weeks. It involves 819 patients at 135 clinical sites in 19 countries, mostly in North America and Europe. It's the largest clinical trial ever conducted for a lupus drug, David C. Stump, executive vice president for research and development, said in the call.
"The BLISS-76 results confirm our view that Benlysta has the potential to become the first new approved drug in decades for people living with systemic lupus," CEO H. Thomas Watkins said in a statement. "We plan to submit marketing applications in the first half of 2010, following discussions with regulatory authorities in the United States, Europe and other regions. We will continue to work with GSK to advance this drug to the market where it may benefit patients with significant need."
"Benlysta is the first medicine developed specifically for lupus that has reached this late stage of clinical development with positive results," Watkins said in the call.
Systemic lupus erythematosus is a chronic, life-threatening autoimmune disease. About 5 million people, including 1.5 million Americans, have various forms of lupus, including systemic lupus erythematosus, according to the Lupus Foundation.
More than 16,000 new cases are reported annually in the U.S., according to federal data. It's most common in people ages 15 to 44, and about 90 percent of patients are women, according to the National Institutes of Health. Black women are about three times more likely than white women to develop lupus.
Symptoms may include extreme fatigue, painful and swollen joints, unexplained fever, skin rash and kidney problems. Lupus can lead to arthritis, kidney failure, heart and lung inflammation, central nervous system abnormalities, inflammation of the blood vessels and blood disorders.
Onset may be acute, resembling an infectious process, or it may be a progression of vague symptoms over several years. Consequently, "diagnosing lupus is often a challenge," according to NIH.
Currently, about 325,000 Americans are seeing a rheumatologist for treatment of systemic lupus, HGS officials said, with about two-thirds with moderate to severe cases taking steroids and immunodepressants. Those patients are the "low-hanging fruit" when it comes to marketing Benlysta, Labinger said in the call. "That's the target market."
Marketing costs should be fairly low, he said.
With just a couple of thousand rheumatologists treating the vast majority of lupus patients, HGS won't "need many sales reps to reach the physicians," Labinger said.
Production shouldn't be a problem, either, Watkins said. The company's Rockville plant is earmarked almost exclusively for manufacturing Benlysta and can "deliver product for about 50,000 patients at a minimum," he said.
"We have plenty of capacity for a good, long time," he said.
HGS is also looking at Benlysta as a possible treatment for multiple sclerosis.