MedImmune, the Gaithersburg research arm of pharmaceutical giant AstraZeneca, is making aggressive moves to expand its footprint in China.

The company said Wednesday it plans to spend $50 million on another production facility in Wuxi, a city near Shanghai on China’s east coast. The company also announced an expansion to a key manufacturing partnership with a Chinese company, WuXi AppTec.

“The goal is to develop biologics locally in China for the Chinese market and also to understand the regulatory environment in China,” said Bing Yao, a senior vice president at MedImmune. “If you manufacture locally in China and develop there in parallel, it’s much faster to market.”

AstraZeneca has had a presence in China since 1993, and the Asian nation is now the company’s ­second-largest drug market. AstraZeneca employs about 11,000 at two factories, a research and development facility and a distribution center, all in the Shanghai area.

In 2012, MedImmune started working with WuXi AppTec, a clinical research and manufacturing company that contracts with pharmaceutical companies. The joint venture focused on MEDI5117, a treatment for rheumatoid arthritis that was accepted for review under China’s food and drug administration in March. WuXi AppTec is helping MedImmune develop a second drug, the nature of which has not been disclosed.

The new partnership deepens the relationship between the two companies by allowing WuXi AppTec to manufacture drugs selected from MedImmune’s pipeline for sale in China.

MedImmune has an option of acquiring WuXi AppTec’s manufacturing capacity through a $100 million investment.

An earlier version incorrectly suggested MedImmune had an option to buy all of WuXi AppTec. The option is only for the manufacturing arm. The post has been updated.