According to a report, UK based Pharma company AstraZeneca PLC (ADR) (NYSE: AZN), and US based Rigel Pharmaceuticals, Inc. (NASDAQ: RIGL) plan to develop a drug to treat rheumatoid arthritis.

As per the deal, Rigel will receive $100 million upfront with an additional $345 million if certain conditions pertaining to sales targets and development are met. AstraZeneca may also pay additional $800 million if Rigel meets certain sales-related milestones for the product called fostamatinib disodium or R788, and achieves considerable commercial success.

The companies estimated the demand for rheumatoid arthritis drug was worth around $13 billion globally last year, up from $1.3 billion in 1998.