FDA approves GSK lupus drug

Administration approval of their lupus drug Benlysta (belimumab), marking the first approval of a new drug for the disease in the US in 50 years.

Specifically, the FDA has approved Benlysta for the treatment of adult patients with active, autoantibody-positive systemic lupus erythematosus (SLE) who are receiving standard therapy.
The approval came without restrictions for use in African-American patients, despite the fact that they did not appear to respond to treatment with Benlysta in clinical studies. The issue is significant, as African-American women have a rate of the disease that is three times higher than Caucasian women.

The FDA said it had determined that there was not enough data in African-Americans to establish a definite conclusion on the matter. As a condition of the approval, the companies will conduct an additional study in the population.

Benlysta, which was developed by HGS, inhibits the production of antibodies that attack healthy cells in lupus patients. The drug is delivered via intravenous infusion. The companies said the therapy will be available to physicians and patients before the end of March.

A consensus forecast complied by Thomson Reuters found that analysts believe global sales of the drug could top $3 billion by 2015.  GSK and HGS signed a co-development and co-commercialisation agreement in 2006 under which they will share equally in sales and marketing expenses, as well as profits.

GSK submitted a Marketing Authorisation Application for Benlysta to the European Medicines Agency in June 2010. The drug has also been filed for approval in Canada, Australia, Switzerland, Russia, Brazil and The Philippines.

The drug's approval in the US was far from a foregone conclusion.  In late 2010, an FDA advisory committee recommended that the agency grant marketing approval, but raised a number of concerns about the drug, including misgivings about a lack of robustness in its efficacy data.

The advisory committee members' conclusion that the drug deserves approval but is not necessarily a major advance in treatment was in line with the stance taken by the FDA's internal reviewers in briefing documents prepared in advance of the committee meeting. The internal reviewers' assessment was generally positive but raised questions about whether the drug's efficacy is sufficient to offset the risks it may pose of suicide, infection and cancer.