(Yicai) Aug 7 -- Hengrui Pharmaceutical’s shares tumbled further today, even though the Chinese company denied that it had been caught up in an anti-corruption campaign in the industry.

After sinking by as much as 6.1 percent in the morning, Hengrui [SHA: 600276] closed 4.7 percent lower at CNY39.13 (USD5.46) a share in Shanghai. In the six trading days since July 31, the stock has lost more than 20 percent of its value.

The company, which has a market value of nearly CNY250 billion (USD34.9 billion), told investors today that there have been no violations, and that its daily operations and business are continuing as normal.

Hengrui previously responded to investor concerns on Aug. 3, saying that it has always attached importance to sales compliance.

The stock prices of many drug companies have taken a hit recently. From July 31 to Aug. 4, the market value of the mainland-listed pharmaceutical and biological firms fell by more than CNY150 billion.

Late last month, China’s top anti-corruption watchdog, the Central Commission for Discipline Inspection, announced a year-long campaign to tackle widespread graft in the pharmaceutical sector.

According to statistics from industry media outlet Saibailan, at least 155 hospital presidents in China have been investigated this year as of July 26, more than double the number in the whole of last year.

Editor: Tom Litting