Meaghan McGeary, PhD
@mk-mcg5.bsky.social
250 followers 690 following 59 posts
NCI K00 Postdoc @ Jacks Lab at MIT Yale 2022 | Holy Cross 2016 "You sort of start thinking anything's possible if you've got enough nerve."
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mk-mcg5.bsky.social
That’s a wrap for the day on antibody drug conjugates at the @mitkochinstitute.bsky.social ! Awesome course on these complicated and exciting molecules (and their relatives)! Lots more exciting anti-cancer science to come 💊 #KIsymposium
mk-mcg5.bsky.social
Modifying chemistry of ADCs, such as through adding polar groups to increase lipophilicity is a separate approach that helps improve ADC pharmacokinetics and tolerability @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Different toxicities can appear with better linkers- indicating a need to better understand the biology of ADCs, as well as improve in other ways to mitigate this toxicity @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
With an unstable linker, side effects mimic those of non-ab mediated systemic treatment with the same drug and safe dosage levels are no different. Stable linkers improve this, safely enabling higher payload doses. TLDR; linker is critical! @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Michael Seganish closes out the day discussing what happens when an ADC payloads detaches, even when it’s supposed to, and gets into circulation instead of into its target cell. Spoiler alert: toxic side effects @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
A new challenge: what to do after development of resistance to ADC treatment- re-treating with a new ADC often doesn’t work. More to learn! #KIsymposium @mitkochinstitute.bsky.social
mk-mcg5.bsky.social
What biomarkers predict success on ADCs? 2 AI models work together to automate image analysis and identify tumor cells that are targetable by ADCs, defining a signature that can be used to identify strong patient candidates. @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Puja Sapra brings perspective on the evolution of the ADC field: much learned and much to be done in terms of improving targets, understanding why different ADCs work differently, and deriving novel combos for future use. @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
More quantitative systems modeling in the Thurber lab has helped identify these balances given lots of data- aiding in figure design of these molecules, which don’t follow the same principles as other drugs. #KIsymposium
mk-mcg5.bsky.social
One approach: lower drug to antibody ratio gets drug into the tissue more efficiently and improves efficacy overall while lowering concerns about toxicity. Second: Use more of a lower potency payload that's more tolerable- It's all about balance. #KIsymposium
mk-mcg5.bsky.social
Mouse models have taught lessons about how ADCs biodistribute + enter tissue which isn't always well- a challenge to be overcome. Higher/more frequent dosages don't always fix this, since there's a risk of toxicity with higher payload. #KIsymposium
mk-mcg5.bsky.social
Challenges remain: most ADCs don't reach the tumor and still circulate (though don't bind), and what does often doesn't distribute through the tumor well. How do we think about fixing?
mk-mcg5.bsky.social
Greg Thurber starts session 3 with perspective on the trajectory of ADCs in the clinic & in research- there's been a steady increase in approved ADC molecules for clinical use since early 2000s! @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Mouse models have taught lessons about how ADCs biodistribute + enter tissue which isn't always well- a challenge to be overcome. Higher/more frequent dosages don't always fix this, since there's a risk of toxicity with higher payload. @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Challenges remain: most ADCs don't reach the tumor and still circulate (though don't bind), and what does often doesn't distribute through the tumor well. How do we think about fixing? @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
With a smaller size and shorter half-life in the body than ADCs, they can get into tumors better, clear out of normal tissues more easily, while still being potent and specific @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Daša Lipovšek expanding today's discussion to include miniprotein radioconjugates, which link target-binding proteins with radioisotopes that can kill cells or be detected with imaging devices. This facilitates greater targeting and functionality. @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Jeremiah Johnson's antibody-bottlebrush conjugates aim to enable loading more drug onto ADCs using hydrophilic sidechain linkers that stabilize more, larger, & combos of payloads. This opens doors to more options for ADC design across more contexts @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Dane Wittrup's lab is innovating ADCs by designing linker-less ADCs, which can enable release of payloads that cells can then take up over time- enabling better and potentially more potent targeting @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
The Boyer lab optimized physically expanding cells and then imaging them in a 96-well plate format- reaching the resolution of higher-power instruments without the cost. Now ADCs at work can be observed! @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Kicking off session 2 is Laurie Boyer, discussing how to visualize how molecules (like ADCs) are traveling into and around cells. Regular light microscopy isn't sufficient and more complicated super-resolution microscopes are expensive and hard to use.
mk-mcg5.bsky.social
Last in Session 1: Timothy Lowinger discusses targeting immune pathways! STING agonism activates innate immunity, but it's important and difficult to deliver this only to tumor lesions. ADCs can bring the drug directly to the tumor microenvironment @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
So much can be done with these models combining in vitro, mouse, and clinical studies- understanding bystander effects of ADCs, studying off-target toxicities, and even creating computer-simulated trials to predict what would happen in patient cohorts. @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
Alison Betts: With the promise of ADCs comes a need to better understand their mechanisms + toxicities. Quantitative Systems Pharmacology modeling uses applied math to study data from ADC trials, aiding in the design of new & improved versions. @mitkochinstitute.bsky.social #KIsymposium
mk-mcg5.bsky.social
It makes sense that this therapy might work in HER2+ patients. But a big question today- why do these also show efficacy in HER2-low (even ultra-low!) patients? Exciting results and lots to learn still... @mitkochinstitute.bsky.social #KIsymposium