mAbsolve

Pick your ideal antibody enhancing mutations with some Fc-ing clarity! Another week and another systematic analysis of Fc variants paper from Geoff Hale and I. Here we look at mutations that are reported to enhance antibody effector function. Much like our story with silencing, there are many variants reported but very few if any real comparisons of them. This leaves researchers unsure which ones to pick! If you want to enhance CDC is hexamerization the way to go or simply enhancing C1q binding? For ADCC is afucosylation better than Fc mutations? We can now start to answer these kinds of questions. mAbsolve doesn't have Fc enhancing mutations. There is no commercial value to us in doing this but Geoff Hale and I felt very strongly that some real comparative data would be of great use to the antibody community. We have tested what we believe to be all the enhancing mutations that have been in the clinic and quite a few that haven't. We acknowledge this is by no means all the mutations in the literature. We focussed on those for enhancing ADCC and/or CDC. With silencing you can make the argument that lower across the board is better. With enhancement it is not so simple. So rather than claiming that one set of mutations is better than another I see this as a menu of options depending on the desired mechanism of action of your antibody. There are still unanswered questions. Can you combine some of these approaches for additive or synergistic impacts? In particular it would be interesting to combine afucosylation with Fc mutations to see if further gains in ADCC are possible. The stability data is also interesting. The better mutations have a major impact on thermal melting temperature (Tm), often bringing it below 50 °C. Is there scope for newer more stable variants? DOI: https://lnkd.in/ecxf-ygt Finally, I'm going to be cheeky and take this as an opportunity to plug my new business Gamma Proteins. Over the last few years working on all the assays for silencing and enhancing Fc variants cost us a small fortune in Fc receptors. It was this frustration that led me to found a business offering high quality Fc receptors at a much more affordable price than existing suppliers. Thanks again to Alastair Davy and Protein Stable for the excellent collaboration on thermal stability and to Janice Reichert and The Antibody Society for their continued support in our efforts to provide robust, reliable and publicly available data to enable data driven selection of optimal Fc variants. Lastly thanks to Geoff Hale, he did the bulk of the work on both papers! If you missed the post about our work on silencing mutations see here: https://lnkd.in/ebsaAzV6 ----- I'm Ian, I post about antibody engineering, recombinant proteins and my journey to bootstrap Gamma Proteins into a leading supplier of Fc receptors. If you like my content please reshare with your network and follow me to see more.

The Good, the Bad and the Ugly: Our analysis of 75 different ways of Fc silencing shows that most variants in the clinic are far from perfect, Many still have substantial effector activity and many mutations compromise the stability of the CH2 domain. Coming soon – a companion analysis of methods for enhancing Fc effector functions! 

📰 NHPRR Partners with mAbsolve to Launch STR-Enhanced Antibodies Highlights: 🐒 NHPRR's tailored pipeline addresses researchers’ needs with critical human disease models 🎯 Our products are designed to maximize translatable findings with species-specific biology in mind ✨ STR optimization attenuates Fc effector function in NHPs and humans, enhancing precision, safety, and translatability 💡Let the best science flourish! At the NHPRR, we specialize in developing therapies for critical nonhuman primate disease models. Our preclinical biomedical products are engineered to translate breakthroughs across human and nonhuman species, considering species-specific biology in every design (epitope, pathway, effector function conservation). Today, we celebrate a milestone—partnering with mAbsolve to incorporate ‘STR’ mutations into our antibodies. This ensures targeted action without unintended immune responses, boosting rigor, effectiveness, and safety. By decreasing Fc-mediated interference (hello Fc-block!) and enhancing the signal-to-noise ratio, STR-enhanced antibodies will produce more robust and reproducible scientific findings. Expect many STR-enhanced antibodies soon! This partnership enhances our resource capabilities and expands the potential for our products to be licensed and clinically developed, following the success of our previous contributions. This aligns directly with our core commitment to facilitate the translation of great scientific ideas into human health! About Nonhuman Primate Reagent Resource - NHPRR The NHPRR has been a leader in advancing biological research with nonhuman primate models for 25 years. By distributing high-quality, specialized research antibodies, NHPRR has supported over 2,000 NIH grants, enabling fundamental discoveries such as the role of CD40-CD40L therapies in pig-to-primate xenotransplantation, the study of AIDS virus reservoirs in macaques, the critical role of CD8+ T cells in elite control of AIDS, and the testing of immunological responses in early monkey models of COVID, contributing to the development of human vaccines. Visit www.nhpreagents.org for more information. About mAbsolve Ltd. mAbsolve founded in the UK by pioneers of therapeutic antibody development and engineering from both Oxford and Cambridge. We have experienced the clinical challenges caused by incomplete silencing of antibodies using LALA, aglycosylated or IgG4 variants. To address this we have developed a best-in-class solution for silencing of antibody effector function. Our STR technology is the only truly silent Fc. Visit www.mabsolve.com for more information. Contacts Diogo Magnani Director, NHPRR Diogo.Magnani@umassmed.edu Ian Wilkinson Chief Scientific Officer, mAbsolve wilkinson@mabsolve.com

We are pleased to announce that our patent filing in the United States has been granted! This adds to the granted patents we have in the UK, Canada, Australia and Japan. Applications in numerous other territories are in progress and we expect them to be granted in due course. All the granted patents have broad claims that don't just cover our preferred silencing mutations (L234S/L235T/G236R, or STR) but a whole range of mutations within the same family that have lower Fc receptor binding than the previous gold standard Fc silencing mutations LALAPG.

I'm making freely available probably the best Excel sheet for antibody sequence analysis and engineering. No license, no fee, no personal info required, no macros and no AI. Input the sequences of your mAb and it will:  - Identify CDRs (Kabat, Chothia, IMGT, you pick)  - Identify sequence liabilities  - Identify signal peptide, V domains and C domains  - Identify mutations in the C domains and their purpose  - Identify species, isotype, allotype  - Enable chimerization of your mAb into almost any other species and isotype at the click of a button (eg, switch mouse IgG1 to human IgG1)  - Introduce any mutation you want into your mAb. Type L234A and that mutation will appear in the correct place in your sequence.  - Provides analysis of 599 IgGs that have been in the clinic Download at antibodyengineering.com. If this proves popular then version 2.0 could potentially reformat any supplied sequences into scFv, Fab, minibody, BiTE, DART, other bispecific formats etc. Background on why I'm doing this: Like many people I spent years thinking Excel was just for accountants. That changed when I started building a small team at MedImmune. We had access to lots of expensive software but my team kept making very basic maths errors in the lab. Out of frustration I started building little Excel sheets. A morning transfecting cells is difficult enough without having to keep working out how much HC and LC to add. Simply input your DNA concentrations and desired transfection volume into my sheet and it will create a worksheet for the day for you. Suddenly our productivity and accuracy shot up. The major impact came when I realised that Excel is a character manipulation tool, this includes letters as well as numbers. With a bit of outside the box thinking and Googling almost anything becomes possible. Translating DNA to Protein is just substitution of one string of text for another. Easy for Excel. Molecular weight determination is just assigning a value to each letter and performing a sum. CDR identification, humanization, Fc analysis or mutation, it's all possible. Hell, I've even analysed Sanger sequencing data in seconds with a home made Excel tool. Of course there are many online tools that can do some of this. They tend to be specific to one task and don't always allow entry of many mAbs once - inputting one at a time is a killer if you have lots. Excel is easy for any user to get to grips with. It has limitations but it's taken me a long way. Many of my connections will have paid for tools that can do all of this and more. There are many people though that don't have access to these tools and might be able to make use of this. Please do comment or reach out if you find any errors or have ideas on useful tools for future versions. If you don’t already follow me, please do so to keep up to date with any new versions I launch. I was hoping to just attach the file to LinkedIn but that doesn’t work, hence the hastily put together website!

What the Fc is up with ADCs? ADCs are the hot topic in antibodies at the moment. Not a week goes by that we don't see news of another ADC entering the clinic or being acquired. Much of the appeal of ADCs is their phenomenal potency but this is a double edged sword and toxicity is a real risk. It's always struck me as odd that ADC developers don't seem to pay much attention to the Fc domain. Surely for most ADCs effector function (i.e. ADCC, ADCP or CDC) isn't part of the primary mechanism of action? If that's the case then the logical approach would be to utilise an Fc domain with reduced effector function to avoid unwanted toxicity from binding to and killing immune cells expressing Fc gamma receptors. ADCs are toxic enough as it is so why run this risk? I always had the feeling this was largely ignored in the ADC space but didn't have the stats to back this up. So yesterday I looked at 70 ADCs, which was most if not all the ADCs that had been in the clinic up to 2022. Over 90% had a fully active human IgG1 Fc domain. This is in stark contrast to antibodies as a whole (from an analysis of +800 INNs) where about 45% are 'silenced' (see https://lnkd.in/e2n3PpeJ). As a developer of one of the best silencing mutations (see https://lnkd.in/eq6P2sGT) I'm somewhat biased, but what's going on here? Are ADC developers missing a trick or is there some logic to the choice of wild type IgG1 in almost all cases? I'd love to hear from people developing ADCs! Note - my analysis doesn't account for the fact that some of these antibodies will utilise the glycans for site-specific conjugation of the payload and this will presumably reduce effector function to some extent. I don't have details on the conjugation process for each mAb in my dataset but I expect that glycan conjugated mAbs only account for a small number (although I accept this is becoming increasingly common in recent years). ----- I'm Ian, I post about antibody engineering, recombinant proteins and my journey to bootstrap Gamma Proteins into a leading supplier of Fc receptors. If you like my content please reshare with your network and follow me to see more.