The Expanding Role of Mass Spec for Peptide Mapping in Multi-Attribute Monitoring Assays

Adopting peptide map MAM assays can bring efficiencies to biotherapeutic monitoring in characterization and late development – and they can streamline method transfer for global QC deployment

Biopharmaceutical laboratories are exploring how to use multi-attribute monitoring (MAM) and LC-MS assays to monitor critical quality attributes (CQAs) of biologics during drug development. MAM assays offer the promise detecting and measuring multiple CQAs simultaneously, which can streamline analytical workflows that have previously taken place in parallel, time-consuming processes.

Two MAM approaches for biotherapeutic analysis are commonly being implemented today:

• Analysis of monoclonal antibody (mAb) subunit mass
• Analysis of peptides from a protein digest – a peptide mapping workflow

I’ve previously discussed the advantages of deploying subunit protein mass MAM assays to achieve higher throughput, to simplify operational processes, and to ensure assay robustness. However, subunit mass MAM assays can be limited in their ability to monitor small mass changes such as deamidations, and they are unable to generate site-specific information when multiple modifications are located on the same subunit fragment.

For these situations, peptide-based analyses are viewed as complementary workflows.

Peptide maps are a reliable identity test for QC product release

High-resolution mass spectrometry and LC-QTof MS peptide mapping methods are indispensable for in-depth protein characterization during biotherapeutics development, whereas optical detection is widely used for peptide mapping identity tests during QC product release. Recently, LC-UV-MS peptide mapping methods have also been developed for product identity release assays, taking advantage of the selectivity and specificity offered by MS detection.

In an article in American Pharmaceutical Review that I referenced for subunit MAM analysis¹, Roche researchers also shared their success in using a LC-MS peptide mapping identity release assay for pegylated Interferon alpha-2a since 2002.

Recently, researchers in China established a validated identity assay for biotherapeutic mAbs using a Waters ACQUITY UPLC-TUV System with an ACQUITY QDa Detector, performed with compliance-ready Empower 3 Chromatography Data Software.² In this study, eight complementary domain region (CDR) peptides were monitored and used to establish a signature CDR profile that could uniquely identify each product among 11 monoclonal antibodies (mAbs) produced at that manufacturing site. Looking ahead, the authors foresee this simple, cost-effective, and robust peptide mapping method being deployed as a routine quality control assay.

Direct quantitative monitoring of multiple product quality attributes

The key benefit of a peptide mapping MAM approach is that it offers site-specific direct assessment of product quality attributes, and this has received significant interest in the past few years. Here are more examples of its application:

• Amgen has been pioneering the deployment of a peptide mapping multi-attribute methodology to streamline biotherapeutics development and QC testing. In a 2015 publication, Amgen researchers described their efforts to monitor multiple product attributes for characterization and process development using high resolution MS1 analysis, and shared their vision of a multi-attribute methodology workflow that can greatly reduce the number of assays needed during process development and quality control.³
• Similarly, Roche Diagnostics published about a peptide MAM approach for high-throughput sample preparation along with LC-MS analysis for quantification of deamidation, isomerization, oxidation, and glycosylation.⁴

In both studies, comparable results were obtained using a peptide mapping MAM method when compared to conventional optical detection assays.

However, peptide mapping MAM using the highly complex research-grade mass spectrometers and informatics tools demonstrated in these studies could be quite challenging to deploy by regulated late development and QC laboratories.

Deploying a QC-friendly peptide mapping MAM platform method

In a recent internal survey of biopharmaceutical scientists, nearly 70% of respondents indicated that they expected to see a significant increase of MS utilization in regulated development and QC in the future.  However, they also see that the biggest challenges for it to be widely adopted lies in overcoming the high costs and complexity of operating and maintaining these advanced tools in regulated laboratory environments, and ensuring consistent, robust performance – as well as addressing data integrity and compliance.

In a 2017 MAbs peer-reviewed article, scientists from AstraZeneca/MedImmune shared their success in developing and qualifying a QC-friendly MAM method that uses the Waters ACQUITY QDa Mass Detector, according to ICH guideline Q2R1⁵, and implementing it to support routine monitoring in downstream process development. In their study, their UPLC-TUV-MS system, operated under Empower 3 Software, provided automated data acquisition, processing, and reporting.

In the paper, authors from AstraZeneca/MedImmune commented, “Compared to traditional high-end mass spectrometers, the [ACQUITY] QDa is cost effective and very easy to operate and maintain.”

Many biopharmaceutical companies are working on developing analytical platform solutions that support routine biopharmaceutical analyses and that can transcend the traditional silos of the discovery, development, and manufacturing/QC pipeline. As such, fit-for-purpose deployment, ease-of-use, and compliance are all factors that need to be considered early on when adopting multi-attribute monitoring methods.

Those are each important attributes that Waters considers in developing analytical technologies, such as mini LC-MS systems, that can be used to efficiently monitor peptides whether you’re working in biologic development or QC.

The final post in this series will discuss the opportunities for MS in regulated laboratories that want to use MAM assays.

Check out my other posts on biopharma labs using MAM methods:

• From Characterization to Late Development, Manufacturing, and QC: The Expanding Role of Mass Spectrometry in Biotherapeutics
• Multi-Attribute Monitoring: The Expanding Role of Mass Spectrometry for mAb Subunit Analysis

References:

1. Haberger et. al. Application of Electrospray Ionization Mass Spectrometry in a Quality Control Laboratory.  Am Pharm Review. 2016, 19(5).
2. Zhang et al. Development and Validation of a Peptide Mapping Method for the Characterization of Adalimumab with QDa Detector. Chromatographia 2016, 79(7), 395-403.
3. Rogers et al. Development of a quantitative mass spectrometry multi-attribute method for characterization, quality control testing and disposition of biologics. MAbs. 2015, 7(5),881-90.
4. Bomans et al. Multi-attribute monitoring of antibody modifications by semi-automated liquid chromatography mass spectrometry peptide mapping. American Pharm. Review, 2016, 16-21.
5. Xu et al. A Quadrupole Dalton-based multi-attribute method for product characterization, process development, and quality control of therapeutic proteins. MAbs. 2017, 9(7),1186-1196.

Additional resources:

1. Play back our on-demand webinar to hear from Waters biopharmaceutical scientists Jing Fang and Robert Birdsall: “Monitoring Product and Process Attributes in Biopharmaceutical Development and QC.”
2. Read application notes about how to use mini LC-MS and mass detection with the ACQUITY QDa Detector for monitoring peptides and glycans.