Ryan Leenay
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rtleenay.bsky.social
Ryan Leenay
@rtleenay.bsky.social
Head of Gene Editing at Lilly.

“We cannot predict the future, but we can invent it” -Dennis Gabor

Likes and retweets are not endorsements.
One could argue that it already has. One drug is enough, one patient is enough.

We’re just getting started.
February 20, 2025 at 12:10 AM
This edit will always live rent free in my head
February 19, 2025 at 11:55 PM
Not something I can answer directly. I assume it’s a time thing, easier to funnel time/energy to the larger mega-round companies we’re seeing more of in biotech?
December 30, 2024 at 12:46 AM
1 is slow, 2 would be quick.

1 - Make this an expectation in time. Seed/accelerators (eg Nucleate) start the push. The best firms start to do this, and it becomes something to expect.

2 - Create leverage. Companies provide specific metrics or other essential info in exchange for deep feedback
December 30, 2024 at 12:41 AM
Yeah completely it would be.

To your original point, it comes down to how this gets incentivized. One thing I’ve seen is a founder aggressively coming back and asking for feedback and/or reasoning for a negative decision. So one aspect of this can be to empower founders to do this.
December 29, 2024 at 11:54 PM
I would worry that a lot of the passes are because they don’t understand, or believe in the differentiation. That’s a tough message to pass on without significant context?
December 29, 2024 at 8:24 PM
Macrophages have a lot of innate pathways to shut down expression from exogenous places. Anecdotally, I’ve seen the same issue of a transduction with no expression on RAW264 cells, but there are ways to design around it: pmc.ncbi.nlm.nih.gov/articles/PMC...
Lentiviral vectors containing mouse Csf1r control elements direct macrophage-restricted expression in multiple species of birds and mammals
The development of macrophages requires signaling through the lineage-restricted receptor Csf1r. Macrophage-restricted expression of transgenic reporters based upon Csf1r requires the highly conserved...
pmc.ncbi.nlm.nih.gov
December 13, 2024 at 11:38 PM
Caribou Biosciences - Jan 2011
Editas Medicine - November 2013
Intellia Therapeutics - November 2014
December 12, 2024 at 11:33 PM
1.0x too, you’re a monster
December 9, 2024 at 11:42 PM
Awesome news Aron, congratulations!!
December 9, 2024 at 12:51 PM
CNN claiming it may have been targeted
December 4, 2024 at 2:57 PM
Completely agree on method-dependence here too, especially in HSC populations where DNA repair kinetics will vary greatly throughout the process.
December 1, 2024 at 6:51 PM