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It is a very large lipopeptide comprising 47 amino acids in its sequence and a myristoylation at the N-terminus. For support of clinical development, we established highly sensitive plasma quantification assays using 100\u00a0\u03bcL of plasma, spanning concentrations of 0.1 to 100\u00a0ng\/mL and 1 to 1000\u00a0ng\/mL with the option to measure ten-fold diluted samples up to 10,000\u00a0ng\/mL. Quantification was performed with UPLC-MS\/MS measurements after extraction with protein precipitation. Both assays were fully validated according to the pertinent guidelines of the FDA and EMA, including incurred sample reanalyses and cross-validation using clinical study samples.<\/jats:p>","DOI":"10.1007\/s00216-021-03384-7","type":"journal-article","created":{"date-parts":[[2021,5,20]],"date-time":"2021-05-20T22:02:15Z","timestamp":1621548135000},"page":"5645-5654","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Intact plasma quantification of the large therapeutic lipopeptide bulevirtide"],"prefix":"10.1007","volume":"413","author":[{"given":"Max","family":"Sauter","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antje","family":"Blank","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Felicitas","family":"Stoll","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natalie","family":"Lutz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Walter E.","family":"Haefeli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00fcrgen","family":"Burhenne","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,5,20]]},"reference":[{"key":"3384_CR1","doi-asserted-by":"publisher","first-page":"1070","DOI":"10.1053\/j.gastro.2013.12.024","volume":"146","author":"Y Ni","year":"2014","unstructured":"Ni Y, Lempp FA, Mehrle S, Nkongolo S, Kaufman C, Falth M, et al. 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The trial was under the legal sponsorship of the Medical Faculty of the Heidelberg University. The trial followed the guideline of Good Clinical Practice, the ethical principles expressed in the Declaration of Helsinki, and all legal requirements for clinical trials in Germany. It was approved by the responsible Ethics Committee of the Medical Faculty of Heidelberg University (AFmo-670\/2016) and the competent national authority (BfArM, EudraCT: 2017-003137-28). Prior to participation in any trial-related procedures, each participant provided written informed consent.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and source of biological material"}},{"value":"Activities for bulevirtide projects at the Department of Clinical Pharmacology and Pharmacoepidemiology were in part funded by Myr GmbH.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}