Bacterial Endotoxin Test using LAL methodology: overcoming interfering factors
The Bacterial Endotoxin Test, using LAL methodology, is a key in-process and final product release test for sterile pharmaceuticals and medical devices. One of the challenges with LAL methodology is overcoming interfering substances as demonstrated by inhibition or enhancement of an endotoxin challenge. Here, Bio Products Laboratory’s Dr Tim Sandle discusses the interfering substances issue and provides some guidance to overcome it.
ASSESSING ENDOTOXIN levels in pharmaceutical drugs and medical devices is necessary to avoid pyrogenic response and septic shock in patients receiving these treatments. Hence, the need to perform tests for endotoxins for injectable products and medical devices is well established. The effects of endotoxin in the human body include high fever, vasodilatation, diarrhoea and foetal shock syndrome. Hence, the importance of end product testing. The Bacterial Endotoxin Test (BET) has been a pharmacopoeia method since 1980 (where it first appeared in the USP). The test, using Limulus Amoebocyte Lysate (LAL) methodology, is described in detail in the European Pharmacopoeia (Ph. Eur., 2.6.14) and US Pharmacopoeia (USP, <85>). The test describes the detection of the most common and significant pyrogenic material found in pharmaceutical production: Gram-negative bacterial endotoxin.1 The main variations between the European and US approaches relate to the acceptability of recombinant lysate and the extent of the validation required.