An exclusive worldwide licensing agreement for the commercialization of fostamatinib disodium (R788) - Rigel's late-stage treatment for rheumatoid arthritis has been signed mutually by Astrazeneca and Rigel Pharmaceuticals.

The drug has completed phase 11 programme and is the oral Spleen Tyrosine Kinase inhibitor for the treatment of rheumatoid arthritis.

The global rheumatoid arthritis market has been valued at around $13bn; up from $1.3bn in 1998. Astra will pay as much as $100m to US drug developer Rigel with an additional sum of $345m of milestone payments, when the deal is finalized.

About $800m will also be given to Rigel for the sales-related milestone payments along with the important stepped double-digit royalties on net sales throughout the world.

The group assumes that the phase III programme will kick off in the second half of 2010 aiming at filing new drug applications to the medical authorities in 2013.