Cuong, 60, is being probed for "negligence that results in serious consequences," according to the Ministry of Public Security.
The incident is the latest development in a counterfeit drug case involving Vietnam Pharma JSC (VN Pharma) and the fake drug branded Health 2000 Canada. Cuong stands accused of violations that allowed VN Pharma to import the fake drug to Vietnam.
Also on Friday, former director of the Bach Mai Hospital Nguyen Quang Tuan, 54, was arrested for alleged violations in the purchase of chemicals and medical equipment, resulting in losses to the state and patients.
Tuan is suspected of involvement in violations regarding bids to purchase chemicals and medical equipment at the Hanoi Heart Hospital where he used to serve as director. The violations increased costs for hospital patients and hurt state interests.
Since May 13, nine people have been detained in the case, including Hoang Thi Ngoc Huong, former deputy director of the Hanoi Heart Hospital and Nguyen Thi Dung Hanh, former head accountant.