2022.07.08: Information on the azido impurity in losartan

Studies characterising the azido impurity in losartan-containing medicinal products have now confirmed that the losartan azido impurity is a non-mutagenic impurity.

Information on this has been published in the CMDh press release "Report from the meeting held on 21-22 June 2022":

CMDh Press Releases

2021.11.02: New information on the azido impurity in losartan

In the context of ongoing investigations in connection with the newly discovered losartan azido impurity, marketing authorisation holders on the German market have increasingly recalled losartan-containing medicinal products on their own responsibility. According to current knowledge, the concerned azido impurity can only be formed during the manufacture of the active ingredient losartan. The recalls are a precautionary measure to ensure patient safety while investigations currently underway on these medicinal products are being completed.

Patients should not discontinue their medication without consulting their physician. Due to the increasing number of recalls, it is possible that there may be restrictions or delays in the availability of losartan-containing medicinal products. It may therefore be necessary for the attending physician to consider switching to an alternative medication.

2021.09.16: Newly discovered impurity (losartan azido impurity)

In 2018, regulatory authorities around the world first became aware of nitrosamine contaminations in certain medicinal products. In the course of the risk mitigation measures taken in the EU since then, another impurity was found in losartan-containing medicinal products. This newly discovered impurity (losartan azido impurity) is an azido impurity, which, according to current knowledge, can only be formed during the manufacture of the active ingredient losartan. Studies have confirmed that the substance is mutagenic. However, preliminary toxicological assessments indicate a significantly lower health risk compared to nitrosamines.

Based on the toxicological studies and taking into account international guidelines, harmonised limits for this impurity are currently being established in consultation with the EDQM, the EMA and the European Member States, based on the treatment duration and the maximum daily dose of the active substance. In the meantime, pharmaceutical companies may recall affected losartan-containing medicinal products on their own responsibility from European markets. This is a precautionary measure to ensure patient safety while the ongoing investigations are being completed. Pharmaceutical companies have been asked to implement appropriate control strategies regarding the detected contamination and, if necessary, to adapt their manufacturing processes.

Patients should not discontinue their medication without consulting their physician. Competent authorities are monitoring medicinal products in the EU to ensure that they meet EU quality standards. The BfArM is in regular contact with the EMA, the EDQM, the EU authorities and the supervisory authorities of the federal states in Germany. The EMA and the national authorities will continue to provide information on the current status of the investigations as required.