The South African Health Products Regulatory Agency (Sahpra) has asked local drug firm Pharma Dynamics to urgently recall medicines for high blood pressure containing valsartan, which it distributes on behalf of the Chinese firm Zhejiang Huahai Pharmaceuticals, due to possible contamination with carcinogenic impurities.
The development follows moves by the European Medicines Agency and the US Food and Drug Administration earlier in July: both regulators have issued recalls for medicines containing generic valsartan made by Zhejiang Huahai Pharmaceuticals and are conducting a safety review.
These products may contain N-nitrosodimethylamine (NDMA), a possible human carcinogen. Sahpra said the presence of NDMA was unexpected, and possibly due to changes in the way valsartan was manufactured.
Sahpra said valsartan-containing medicines were commonly used to treat patients with high blood pressure to reduce complications such as heart attack and stroke. They are also used in patients who have had heart failure or a recent heart attack. Valsartan is available on its own or in combination with other medicines.
The recall does not apply to all valsartan-containing medicines, but only to those made by Zhejiang Huahai Pharmaceuticals.
Sahpra advised patients taking the affected medicines to urgently consult their pharmacist or doctor, and continue taking their pills until they had a replacement.
"Sahpra will continue to investigate and assess whether the impurity may pose any risk to patients, and collect more data on the safety of valsartan-containing medicines as it becomes available. Any new information or recommendations will be communicated to the public," it said in a statement.
It urged healthcare professionals to report any adverse reactions associated with valsartan-containing medicines to its pharmacovigilance unit at 012-395-9133 or to the National Adverse Drug Event Monitoring Centre at 021-4471618, or by using the reporting form available on its website.
Pharma Dynamics said its affected products were Dynaval Co 80/12.5mg, 160/12.5mg and 160/25mg.
CEO Erik Roos said this was the first product recall to affect the 17-year-old company.
"We have been actively working with Sahpra to ensure a swift recall of all affected products and we will issue a full refund for all returned Dynaval Co products," he said.
Roos said neither Dynaval 80mg and 160mg tablets, nor any other Pharma Dynamics products were affected by the recall.