Strategy and validation of a consistent and reproducible nucleic acid technique for mycoplasma detection in advanced therapy medicinal products

Abstract

Advanced therapy medicinal products (ATMP) are required to maintain their quality and safety throughout the production cycle, and they must be free of microbial contaminations. Among them, mycoplasma contaminations are difficult to detect and undesirable in ATMP, especially for immunosuppressed patients. Mycoplasma detection tests suggested by European Pharmacopoeia are the "culture method" and "indicator cell culture method" which, despite their effectiveness, are time consuming and laborious. Alternative methods are accepted, provided they are adequate and their results are comparable with those of the standard methods. To validate a novel in-house method, we performed and optimized, a real time PCR protocol, using a commercial kit and an automatic extraction system, in which we tested different volumes of matrix, maximizing the detection sensitivity. The results were compared with those obtained with the gold standard methods. From a volume of 10 ml, we were able to recognize all the mycoplasmas specified by the European Pharmacopoeia, defined as genomic copies per colony forming unit ratio (GC/CFU). Our strategy allows to achieve faster and reproducible results when compared with conventional methods and meets the sensitivity and robustness criteria required for an alternative approach to mycoplasmas detection for in-process and product-release testing of ATMP.

Keywords: Advanced therapy medicinal products (ATMP); Mycoplasmas; Nucleic acid amplification technique (NAT); Validation.