By a 10-1 vote, a government advisory panel Tuesday backed Roche Holding AG's (RHHBY) drug Actemra to treat moderate to severe rheumatoid arthritis, despite safety concerns about how the treatment will affect the liver. The U.S. Food and Drug Administration, which sponsored the panel, usually clears drugs that win support from advisory panels. A final decision is expected by Sept. 18.

The Hoffmann-La Roche, Inc. drug is already being used in Japan, and the Food and Drug Administration must now decide whether to give its approval for patients in the United States.

Roche wants approval to use Actemra to treat rheumatoid arthritis, or RA, in adults. The disease can destroy joints and causes chronic pain for patients.

FDA officials said the drug appears effective for treating patients with moderate to severely active rheumatoid arthritis, but has been linked to serious infections, malignancies and liver problems.

Known as “RA,” the disease affects about 2.5 million Americans and usually strikes in early adulthood or middle age. Women are more exposed to the disease, which can lead to an early death if untreated. It is more serious than the arthritis which is associated with age and is characterized by joint pain.

Actemra works by blocking the effect of a certain protein associated with inflammation. It blocks interleukin-6 (IL-6), an immune-system protein involved in inflammation. Other widely used drugs block a protein called tumor necrosis factor (TNF).The drug is expected to bring in anywhere from $788 million to $4 billion in revenue beginning in 2012, assuming it's approved.

“It's always good to have new options for treating patients, but with a new drug, you don't know what the side-effect profile is,” said Dr. Patience White, chief public health officer at the Arthritis Foundation, according to the Associated Press. “In RA, you have a nearly 100 percent chance of being totally disabled and dying early, and you have a small chance of the side effects we're talking about.”