GlaxoSmithKline has filed its investigational eagerly-anticipated lupus drug Benlysta, developed in tandem with Human Genome Sciences, with regulators in Europe.

GSK has submitted a marketing authorisation application to the European Medicines Agency for Benlysta (belimumab) for reducing disease activity in adults with autoantibody-positive systemic lupus erythematosus. The filing includes the results of two Phase III trials, known as BLISS-52 and BLISS-76, which showed that Benlysta plus standard of care achieved a statistically significant improvement in patient response rate compared with placebo. The study results, which involved nearly 1,700 patients, also showed that belimumab, the first in a new class of drugs called BLyS-specific inhibitors, was generally well tolerated.

HGS chief executive Thomas Watkins said Benlysta “has the potential to become the first new approved drug for systemic lupus in more than 50 years,” He added that his company and GSK plan to submit a Biologics License Application to the US Food and Drug Administration before the end of this month.

Analysts believe that Benlysta could be worth as much as $3 billion a year if regulators are sufficiently impressed with the data. Many companies have tried to get treatments for lupus to market and until now all have failed.