On Monday, Human Genome announced that its experimental lupus drug Benlysta was successful in a second large, late-stage clinical trial, which was needed for the company to file for FDA approval of the treatment. If approved, Benlysta would the first new treatment for the disease in 50 years.
Lupus is a chronic and often disabling autoimmune disease, which causes the immune system to attack the body's own tissue and organs. It has no known cure. Approximately five million people worldwide, including about 1.5 million in the United States, suffer from various forms of lupus; studies estimate that in the U.S., over 300,000 suffer from the most common type, systemic lupus erythematosus, with a similar number in Europe.
Lupus usually strikes women ages 14 to 45; 90 percent of those diagnosed are female. Lupus can affect many parts of the body, including the skin, kidneys, heart, lungs, joints, blood vessels and brain. Because cases vary widely in terms of symptoms and severity, the disease has been challenging for researchers and drug developers.
The reaction to the announcement from Human Genome and its partner, GlaxoSmithKline (GSK), is no surprise then, even if the results from this latest clinical trial were not quite as convincing as those from the initial study. The trial was a multicenter study of 826 patients at 133 clinical sites in 19 countries. The 52-week study found that 43.2 percent of patients who took the high dose of the experimental lupus drug Benlysta (generic name: belimumab) achieved improvement in symptoms with no significant worsening of disease in individual organs, compared with 33.8 percent for those with placebo plus standard of care. The lower dose showed no statistical significance. The result met the main goal of the clinical trial.
In the previous study, a low dose of Benlysta improved symptoms in 51.7 percent of patients, while a placebo helped 43.6 percent. A higher dose of Benlysta improved symptoms for 57.6 percent. One reason for the difference could be that the second trial took place primarily in North America and Europe, while the first trial took place in Asia, South America and Eastern Europe, places where the standard of medical care may be lower.
"A Pivotal Moment in Lupus Research"
Benlysta works by inhibiting the immune system's response to lupus. The companies said that the study results also showed that Benlysta was generally well tolerated with overall adverse event rates comparable to placebo treatment groups.
In July, HGS said it plans to charge around $15,000-$20,000 a year for the therapy. Analysts put a price tag of up to $30,000 a year on the drug, and say it could be on the market by 2010. The two companies, which will share profits from Benlysta on a 50-50 basis, plan to ask for regulatory approval in the first half of 2010. Analysts expect the drug to reach sales of over $1 billion to $3 billion.
The Lupus Research Institute and its affiliates congratulated the companies. "This is a pivotal moment in lupus research," said Margaret G. Dowd, president of the LRI, an organization that pioneers lupus research. "Benlysta represents new hope for the 1.5 million Americans with lupus and millions more worldwide who have suffered without a safe and effective treatment for more than 50 years."
"The Benlysta trials are the first well-designed and conducted, comprehensive studies that assessed several measurements of disease," said Daniel J. Wallace, M.D., clinical professor of medicine at the David Geffen School of Medicine at UCLA. "These trials are a breakthrough for utilizing a methodology that enables researchers to demonstrate disease improvement, and represent a solid path forward for people with lupus."