Organic synthesis or cell culture (in the case of biotherapeutics) often leads to less than 100% production. Consequently, a range of impurities are made together with any medicine. In addition, impurities can come from anything within the production or packaging chain that the medicine comes into contact with. Regulatory authorities focus on the control of impurities and typically incorporate limits that restrict impurity levels present in active pharmaceutical ingredients (APIs) and drug formulations. Typically these impurities are divided into three classes: organic impurities, inorganic impurities, and residual solvents.
Pharmaceutical impurities are unwanted chemicals present in starting and intermediate materials used in the manufacturing of active pharmaceutical ingredients (API) which, even in small amounts, can affect the efficiency of the pharmaceutical product and ultimately can pose health risks to patients.
Nevirapine is a non-nucleoside reverse transcriptase inhibitor with activity against human immunodeficiency virus type 1 (HIV-1), currently marketed for the treatment of HIV-1 infected adults. The United States Pharmacopeia (USP) uses a reversed-phase high-performance liquid chromatography (HPLC) separation with UV detection to determine nevirapine and its impurities.
The drug metoprolol succinate USP is a selective beta-adrenoreceptor antagonist that reduces chest pain and lowers high blood pressure. Several pharmacopoeias (United States Pharmacopoeia, European Pharmacopoeia, and British Pharmacopoeia) have indicated acceptable levels of impurities allowed by drug manufacturers.
Tenofovir belongs to a class of antiretroviral drugs known as nucleotide analogue reverse transcriptase inhibitors (NRTIs), which block reverse transcriptase, an enzyme crucial to viral production. Tenofovir is in formulation given as the prodrug tenofovir disoproxil fumarate (TDF) in combination with the nucleoside reverse-transcriptase inhibitor emtricitabine.
This poster from ASMS 2015 illustrates an effective workflow for pharmaceutical API impurity analysis of Fexofenadine, a commercial antihistamine drug, using HR-LCMS and Thermo Scientific Compound Discoverer.
Discuss how to overcome the challenges encountered in pharmaceutical intermediate impurity analysis, and how to deliver a new degree of confidence in the identification of unknown volatile and semi-volatile impurities.
Lab ideas for people – like yourself– in analytical labs making medicines, directed by topics, ideas and thoughts from your fellow medicine makers. Each month, a new theme addresses challenges and solutions around technology and workflows.