Thoughts on HRMS in Regulated Bioanalysis

Fresh from AAPS PharmSci 360 2024, I’ve been reflecting on the High-Resolution Mass Spectrometry (HRMS) in Bioanalysis symposium where I had the privilege of speaking. It’s always enlightening to digest the insights shared by other speakers and the feedback received during Q&A sessions and hallway conversations. Our main objective for the symposium was to discuss why the adoption of HRMS in bioanalysis hasn’t progressed as rapidly as anticipated a decade ago. I’m pleased that we tackled this topic head-on, both through individual presentations and the open panel discussion. I’m also proud of our bioanalytical community’s engagement in these discussions, showcasing our passion and commitment to advancing our discipline and science.

So, what were my takeaways from the session? It was clear that while HRMS has proven useful for certain applications, it isn’t a replacement for traditional triple quadrupole (QqQ) bioanalysis. From Keyang Xu’s ADC investigations of biotransformation/stability to the applications presented by Eric Thomas and myself, the theme was that HRMS enables bioanalytical strategies that either QqQ instruments can’t achieve or that HRMS can perform better. Whether HRMS is necessary is a separate question, and this gets to the heart of the adoption issue. John Kadavil highlighted that HRMS has not yet featured heavily in regulatory submissions, a meaningful metric of past record but not necessarily a predictor of the future.

As with any new technique, adoption must offer significant advances or enable achievements that were previously impossible. In the pursuit of “juice that is worth the squeeze,” we must address some real and inconvenient aspects of HRMS. File sizes are approximately 30 times larger than QqQ SIM file sizes, new software validation is a significant obstacle (though we manage this for other operating systems and software versions for QqQ instruments), and training staff to switch between QqQ and HRMS is crucial for laboratory logistics. Here is where I came away from PharmSci 360 with the answer for myself as to why HRMS has not met the decade ago expectations of adoption … it didn’t need to! QqQ instruments have also advanced, with increased sensitivities, improved robustness, ease of use, and expanded applications to macromolecules through hybrid immunoaffinity, digestion, and surrogate peptide quantitation.

The question remains whether we have reached the inflection point of applications, as suggested during the panel session. For regulated bioanalytical quantification, this is a critical consideration. Oligonucleotide moieties, cyclic peptides, bile acids, steroids, and other biologic analytes where MS/MS fragmentation struggles to meet sensitivity needs bring HRMS into focus. Peptide/protein applications without immunoaffinity capture reagents present another significant opportunity for HRMS to meet objectives practically. Considering current trends in modern drug/analyte modalities, I believe the trajectory of HRMS adoption in bioanalysis will accelerate because it is, and can be, the right tool for the right job. While I still expect QqQ to feature in capital budgets, the demands are changing, and the old tools won’t meet the new needs. HRMS simply adds to our bioanalytical toolbox with critical advantages. Let’s commit to the squeeze that is required, or we will miss the juice.