That's not the way I understand it. China's drug prices are government controlled and normally set at domestic cost plus 5%. Then there is an additional 12%-15% added for the distribution channel. If a drug is then used heavily, the price is cut by the government.
Your understanding is incorrect. China's drug prices are a lot more complex than that. The government doesn't uniformly set all drug prices. They set prices for so called essential drugs only.
Research firm Datamonitor comments that the price cuts in Dec2010 represent “mixed messages” for multinational pharmaceutical companies. One the one hand, some firms are pushing for their products to be included on China’s National Reimbursement Drug List (NRDL), despite the risk of price reductions, while others are “lobbying for the Chinese government to introduce a more balanced system and to reward innovation and quality,” said the firm.