The Beijing No. 1 Intermediate People's Court will hold an open trial in mid-May, and the case is expected to conclude by the end of the month, according to a report in China Business News on Tuesday.

The newspaper quoted a "well-informed source" as saying prosecutors were charging Zheng with dereliction of duty, taking bribes and leading a "dissolute life".

Zheng, who retired before the allegations and first came under investigation by the Communist Party of China's Central Commission for Discipline Inspection in December, was expelled from the Communist Party in March.

More than 30 other people, including many high-ranking officials such as Cao Wenzhuang, former director of the registration department of the SFDA, are involved in the case.

Zheng could apply to receive medical treatment on bail after the court passes judgement because he suffers from diabetes.

"Zheng's hair has turned completely grey," said the source. "When Zheng was told that his wife and son were arrested for involvement in corruption, he cried."

The source said Zheng's wife, Liu Naixue, and his son, Zheng Hairong, were charged with taking bribes from pharmaceutical companies mainly in Shanghai and Guangzhou.

Another newspaper, 21st Century Business Herald, reported last month that the bribes allegedly taken by Zheng, including cash and gifts, were worth more than five million yuan (about 650,000 U.S. dollars).

Zheng was appointed director of the SFDA when it was created in 1998.

In 2002, China adopted national standards for approving medicines. All new medicines had to be approved by the SFDA before they could be put on the market.

Zheng promoted a certification system called Good Manufacturing Practice (GMP), which was brought into disrepute by a series of health scares and corruption scandals.

SFDA has ordered its officials to divest themselves of 3.5 million shares that they held in pharmaceutical companies, including a large enterprise in east China's Shandong Province.

In addition, SFDA staff registered and handed in gifts and money valued at over 2.6 million yuan (325,000 U.S. dollars).

Currently, SFDA is drafting new medicine approval regulations and a new standard of the GMP system.