A progressive disease often leading to chronic pain and severe, incapacitating disabilities, Rheumatoid Arthritis (RA) causes the body’s immune system to inflame, destroying soft tissue and eroding bone and cartilage. The current treatment options for RA have potentially significant side effects and limitations.

Rigel is focusing its RA program on the development of an oral disease modifying anti-rheumatic drug (DMARD) to be used early in the course of the disease.

Unlike current RA treatments, some of which are delivered by injection, R788 has a novel mechanism of action, blocking Fc receptor signaling in macrophages and B-cells that promote swelling and inflammatory response. And because it is delivered orally, R788 may help patients overcome treatment obstacles often encountered with injectable drugs.

Planned for use in the early stages of the disease when DMARD's are most effective, R788 will potentially diminish swelling and tissue destruction, preventing the progression to major bone and cartilage destruction.

RA suffers may have a chance to lead active, healthy lifestyles.

The worldwide market for RA drugs exceeded $13 billion in 2007.