Human Genome Sciences Inc.'s treatment for rheumatoid arthritis has cleared a major testing hurdle, according to company officials, marking the first time one of the drugs developed by the Rockville firm has proved effective in patients.
Results of a recently completed study show that LymphoStat-B reduced signs and symptoms of the often debilitating disease in 31 percent of 283 patients after six months of treatment. The results set the stage for broader-scale testing of the drug, the final step before seeking regulatory approval and bringing the drug to market.
The company has had two other drugs fail in initial human testing since its founding in 1992.
Later this year, the company is expecting test results to determine whether the drug helps patients with lupus, another inflammatory disease that affects mostly women and causes severe joint pain and fatigue, among other symptoms.
While several treatments are approved for rheumatoid arthritis, there are none for lupus, which analysts have said makes that upcoming round of tests even more important for the company.
Chief executive H. Thomas Watkins said the company's plans for the drug depend on further analysis of the study data with federal regulators, disease specialists, and GlaxoSmithKline PLC, which has the option to split development costs and profits for the drug.
Human Genome executives did not rule out the option of seeking regulatory approval for just lupus treatment, particularly because the rheumatoid arthritis market is so competitive.
Company scientists began developing LymphoStat-B in the late 1990s, when they discovered a protein called BLyS, which is required for disease-fighting cells to mature and produce antibodies that attack viruses and bacteria.
Sometimes those disease-fighting cells instead produce cells that attack the body's tissue. Most people's immune systems kill those cells. But many don't, causing autoimmune diseases such as lupus and rheumatoid arthritis.
Research studies by Human Genome scientists, and others, have shown that too much BLyS actually causes so much cell activity that the malicious antibodies thrive and start attacking the body.
LymphoStat-B attacks BLyS and limits the production of those damaging cells.