LONDON (Reuters) - The European Medicines Agency estimates there could be one extra case of cancer for every 5,000 patients taking a common blood pressure and heart drug manufactured in bulk by a Chinese company that has been found to contain an impurity.
The alarm over valsartan was first raised in July, prompting a global recall of affected pills. The EMA believes the problem likely dates back to changes in manufacturing processes at Zhejiang Huahai Pharmaceutical in 2012.
In an update on its investigation issued on Thursday, the European drugs watchdog said its one-in-5,000 risk assessment was based on patients taking the highest valsartan dose every day for seven years.
NDMA, or N-nitrosodimethylamine, is classified as a probable human carcinogen. Based on results from laboratory tests, it may cause cancer with long-term use.
Reporting by Ben Hirschler; Editing by Susan Fenton