Following a preliminary evaluation, the European Medicines Agency (EMA) estimates that there could be one extra case of cancer for every 5,000 patients who were taking the recently-recalled contaminated valsartan medicines at the highest valsartan dose (320mg) every day for seven years. This preliminary estimate is based on the assumption that the N-nitrosodimethylamine (NDMA) present in the active substance is carried over in the final product in the same amount.
The EMA review was initiated last month after it emerged that valsartan products supplied by Zhejiang Huahai Pharmaceuticals might contain the probable human carcinogen NDMA. It is believed the impurity was a side product of a new manufacturing process that was introduced in 2012. No other active substances produced by the company are affected.
These latest estimates from the review process have been extrapolated from animal studies and the Agency says they should be considered in the context of the lifetime risk of cancer in the EU (1 in 3) and NDMA exposure from other sources.
All valsartan medicines containing the active substance from Zhejiang Huahai Pharmaceuticals have been recalled throughout the EU. Medicines not affected by the impurity remain available.