Oct 19, 2026 · 47 min
Listen from 4:26
Listen at 4:26
Bostwick argues CNS breakthroughs need better biology and delivery
Investing In Tomorrow's CNS Breakthroughs With Breyer Capital's Bret Bostwick, M.D.
CNS drug development remains constrained by difficult translation, limited brain delivery, and the gap between promising platforms and clinical proof.
- 1Human genetic evidence can sharpen target selection more reliably than many conventional preclinical models.
- 2RNA medicines, psychedelics, gene therapies, and AI each offer promise but require modality-specific development strategies.
- 3Breyer Capital prioritizes differentiated science and patient partnerships, with blood-brain barrier delivery a central unmet need.
Don't miss
Bostwick identifies blood-brain barrier delivery as his current priority and questions whether existing transferrin-receptor shuttles can serve more than limited applications.
The brief
Bret L. Bostwick’s path from medical genetics and Alnylam to venture investing shapes a practical view of biotech: start with human biology, then solve the translational problem.
CNS development magnifies every weakness in the pipeline, from the blood-brain barrier and neuronal scale to brain biology that animal models often fail to capture.
Bostwick compares RNA interference, antisense drugs, gene therapy, gene editing, psychedelics, and AI without treating any platform as a substitute for clinical strategy.
His investment framework favors early science with biological ground truth, clear unmet need, and teams capable of pursuing the fastest credible path to patients.
The sharpest priority is delivery: existing transferrin-receptor shuttles may have narrow applications, leaving room for more precise ways to cross the blood-brain barrier.
China’s biotech growth and AI’s expanding role reinforce the same lesson: scale matters less than differentiated science, credible translation, and disciplined development.
What was said on this episode
21 statements · 9 positive · 9 negative · 3 neutral
Genetically validated targets can reduce pharmacology’s traditional failure rate.
“it really is a way of changing what is a traditionally 90% failure rate in our field of pharmacology into a much lower rate of failure.”
Listen at 7:37
APOE E4 homozygotes have ten- to twenty-fold higher Alzheimer’s disease rates.
“individuals that are E4. E4 homozygous have, you know, a 10 to 20 fold higher rate of Alzheimer's disease.”
Listen at 10:05
Human genetic evidence lowers clinical-trial risk for genetically validated targets.
“these targets have less risks as we go into clinical trials because we've already learned some of what modifying that target will do based on the natural experiments that have happened in human genetics.”
Listen at 11:05
Oligonucleotide therapies, especially siRNA, are among the best CNS modalities.
“So, yes, I'm a huge bull behind, you know, oligonucleotide therapies, siRNA, I think being one of the best, but also, you know, editing at the DNA level as well.”
Listen at 16:39
Identifying CNS drug targets is not the primary development obstacle.
“I do not think that understanding what the target is the primary obstacle in the cns”
Listen at 17:42
The blood-brain barrier excludes most designed drugs from the brain.
“The blood, brain,”
Listen at 18:34
Breyer Capital does not restrict CNS investments to a particular modality.
“we're very modality agnostic at Briar Capital.”
Listen at 23:23
Breyer Capital has no dedicated psychedelic-medicine investment thesis.
“We do not have a particular thesis on it.”
Listen at 24:34
Breyer Capital seeks high-risk technologies capable of changing disease treatment paradigms.
“we're really trying to find breakthroughs. We're trying to back high risk breakthrough technology that can paradigm shift the way doctors approach a particular disease area.”
Listen at 26:59
Breyer Capital operates as an evergreen fund and remains patient with portfolio companies.
“we don't have any particular fund cycle. We're an evergreen fund and we continue to stick with our companies and we can be patient.”
Listen at 28:31
Mouse data poorly predicts clinical success, whereas human genetics provides stronger guidance.
“mice lie. They lie. They're not a very good proxy for what will work in clinic. Human genetics doesn't lie, right?”
Listen at 30:00
Preclinical companies should pursue the fastest credible path to first-in-human trials.
“chart the quickest path, the fastest, most agile path you can to get to clinical trial, that first in-human trial.”
Listen at 30:18
China has become a global hub for cutting-edge drug development.
“The Chinese biotech system has matured tremendously in just the last few years. And it's now like a hub, a global hub for drug development, cutting edge drug development.”
Listen at 33:42
U.S. biotechs copying China’s lower-cost model will struggle.
“if you're a US biotech company today and you are going to try to run the same playbook as a Chinese biotech, but do it cheaper, if that's your business strategy, that's going to be tough.”
Listen at 36:43
Copycat strategies are unlikely to succeed for U.S. biotech companies.
“No copycat strategy because that's just not likely to succeed.”
Listen at 37:38
Drug development, rather than discovery, is biotech’s primary difficulty.
“drug discovery is easy. It's easy to discover drugs. We have known pathways. What is really hard is drug development.”
Listen at 39:31
AI has not yet meaningfully shortened biomedical development timelines.
“we really haven't seen AI in a meaningful way come in and compress biomedical timelines.”
Listen at 39:52
Testing whether a molecule can pass Phase 1 may cost ten to twenty million dollars.
“it's still going to cost probably $10 to $20 million per molecule to figure out whether you can even get through phase one”
Listen at 40:14
Clinical AI systems should require human verification.
“there needs to be thoughtful systems in place where there's a necessary human in the loop for verification.”
Listen at 42:54
Transferrin-receptor shuttles will solve brain delivery only for a small subset of applications.
“I think that that will only be a solution for a very small subset of where we want to deliver in the brain”
Listen at 43:58
In vivo drug manufacturing using mRNA technology will be transformative.
“we think that this is going to be transformative.”
Listen at 45:16
Statements are attributed to the speaker as said on the episode and reflect their view at the time, not PodLume's. They are not advice.
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