BioPharm

www.biopharminternational.com April 2019 BioPharm International eBook 13 Outsourcing Resources Quality Control TAKING MS INTO THE QC LAB BioPharm: W hy was t he M A M approach developed? Rogers: Scientists at Amgen had been working on ways to improve QC testing before I joined the com- pany in 2012. Originally, the proj- ect was called "Mass Spectroscopy (MS) in QC," because its goal was to replace some of the current QC release methods with a mass spec- based method. A f ter I joined the g roup, we developed a proof of principle, since we could demonstrate a cor- relation between MS data and con- ventional product quality assays. Within a short time, we were able to expand the method and our goals for it. It was no longer just about using MS in QC, but seeing how many attributes we could tar- get with the method. BioPharm: How did you get sup- port for the project? Rogers: Senior management at A mgen had been supportive of this approach to quality control. Support from the top level of the organization helped win over QC staffers who, initially, were very hesitant about using the method. B i o Ph a r m: How do e s p e p t ide mapping figure into MAM? R o g e r s : P e p t i d e m a p p i n g has been used for decades. The approach involves digesting a test sample of a biopharmaceutical, and then using an algorithm to search the data to identify pep- tides and post-translational modi- fications that are present on the product. After a molecule has been characterized, attributes are then monitored by relative quantitation, which compares the modified pep- tides with parent peptides. W h a t d i f f e r e n t i a t e s M A M from conventional peptide map- ping is the pur it y component. Conventional release assays such as capillary electrophoresis and cation exchange chromatography are considered purity assays. In order to replace these traditional QC release methods, MAM had to have a comparable purity compo- nent associated with it. To address this issue, a new peak detection feature was incorporated into the method, enabling a way to perform differential analysis between a reference standard injec- tion and each test sample. Instead of leveraging a person to inter- pret an electropherogram (a chart generated when electrophoresis is used) or an ultra-violet (UV) chro- matogram, we use software to go through and identify differences between the test sample and refer- ence standard. T h e m a s s s p e c t r o m e t e r acqu i r e s f u l l s c a n d at a . M A M does not need every peak to be completely resolved. We are able to leverage software to see every- thing underneath a single peak. A si ngle pea k i n t he tot a l ion chromatog ram could consist of three to five species. BioPharm: Did you develop the required software inhouse? R o g e r s : I n it ia l ly, we worked exclusively with Thermo Fisher Scientific. We acquired data using an Exactive Plus MS and then used Pinpoint for PTM quantification and Sieve for new peak detection. Those two pieces of software still exist but aren't being supported by Thermo anymore. Other ana- lytical software vendors, including Protein Metrics, Genedata, Sciex, Agilent, Bruker and Waters, are also incorporating MAM analysis into their software platforms. Cu r rent ly, T her mo has inte - grated P T M quantif ication and new peak- detection capabilities into its BioPharma Finder soft- ware. The software is not yet 21 Code of Federal Regulations Part 11- complia nt, but its at t r ibute monitoring method can be incor- porated into Thermo's compliant software, Chromeleon. So, if you are work ing on T her mo's plat- form, and transferring an MAM r e le a s e met ho d i nto Q C , you wou ld develop t he met hod i n BioPharma Finder and then trans- fer it to Chromeleon for use in QC. GAINING BUYIN FOR THE METHOD BioPharm: Many new technology advocates at pharma companies f i nd ma nage me nt resist a nt to change. How did you get senior management's approval for MAM so quickly? Rogers: Amgen has always had a large technolog y development e f for t . T he c o mp a ny 's s e n io r managers wanted us to test new methods for QC, and it all came down to us being able to demon- strate proof of principle. W hat helped was the fact that many senior managers at the company had strong science backgrounds, for example, vice-president Jim Thomas, could critically evaluate data and see the benefit of doing these types of assays in QC. BioPharm: How did you get the QC staff to become more comfort- able using this approach? Rogers: The Exactive series of MS tools is user f r iendly, w ith straightforward calibration and overall robustness. As a result, equipment upt ime using t hese tools is as good or better than that for a conventional ultra high- pressure liquid chromatography (UHPLC) assay. Fortunately, the QC department had already run UV-based peptide maps before, and had also quanti- fied attribures based on the UV trace. As a result, they were confi- dent doing trypsin digestions and transferring in a reverse-phase gra- dient to separate peptides. All we

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