The Japanese health ministry is making final arrangements to file a criminal complaint with prosecutors against Novartis Pharma K.K. over alleged exaggerated advertising for a blood pressure-lowering drug, in violation of the pharmaceutical affairs law, ministry officials said Wednesday.

The Health, Labor and Welfare Ministry initially planned to file the complaint with the Tokyo District Public Prosecutors Office on Wednesday, but delayed the move to make further preliminary arrangements with the prosecutors, the officials said.

To promote the drug Diovan, Novartis Pharma used clinical studies by two Japanese universities that concluded the drug reduced the risk of cerebral stroke and angina, but the studies were found to contain false data.

The Japanese sales arm of Swiss pharmaceutical giant Novartis has claimed that it was not aware of the false data in the reports.

The Kyoto Prefectural University of Medicine and the Tokyo-based Jikei University School of Medicine published their respective reports on their studies in or after 2007, in which a Novartis Pharma employee took part. The company cited the reports around 700 times in ads in medical journals and leaflets for doctors.

In July 2013, the universities said they had found that clinical data in the reports had been manipulated.

Last September, a health ministry panel said the company's use of the universities' reports to promote sales of Diovan could amount to exaggerated advertising.

The two universities are among five Japanese universities that conducted clinical studies in or after 2002 on the drug.

Annual Diovan sales in Japan have exceeded 100 billion yen since 2005. The drug is sold in around 100 countries.