Essays · The Hillman Letter · Long-form
Writing. Operator notes, in public.
Long-form essays on FDA, frontier therapeutics, and capital. Operator notes from inside the work.
Targeted Osmotic Lysis (TOL) is investigational. It has not been approved by the FDA for any indication. It is not available as a treatment. Exosome and mesenchymal stem cell-derived extracellular vesicle products are not approved by the FDA for any indication. Content on this page is educational and describes published scientific literature. It does not describe an available treatment, it does not report results in patients, and it does not offer access to any therapy.
Long-form writing.
The Spreadsheet Knew
2026-10-19 · Latest
Two September and October settlements show how a stalled internal review turns into a False Claims Act case. The 60-day overpayment clock is the reason. Read on Substack.
The Shred Bin Is Evidence
DOI: https://doi.org/10.5281/zenodo.23352303 (paper page)
2026-10-12
Retention schedules and litigation holds are one system. Build it before the subpoena lands, not after. Read on Substack.
How to Write a Healthcare Compliance Expert Report That Survives Rule 702
DOI: https://doi.org/10.5281/zenodo.23352301 (paper page)
2026-10-05
The 2023 amendment moved gatekeeping from theory to practice. Read on Substack.
Pathway Diligence Before the Check Clears
DOI: https://doi.org/10.5281/zenodo.23352299 (paper page)
2026-09-28
An operator checklist for family-office diligence before the wire. Read on Substack.
The R3 Medical Warning Letter Is a Pattern, Not a Mood
DOI: https://doi.org/10.5281/zenodo.23352297 (paper page)
2026-09-21
What operators should extract from FDA warning-letter patterns in regenerative clinics. Read on Substack.
The Same Surgical Procedure Loophole Is Closed. Here Is What the Cell Surgical Network Injunction Means for Everyone Building a Cell or Exosome Product.
2026-09-14
Eight years, one reversal, and a nine-page order that ends the argument. Read on Substack.
After the Tissue Grey Market Warning Letters, What Clinics Should Pressure-Test Before a CID Arrives
DOI: https://doi.org/10.5281/zenodo.23352295
2026-09-07
A clinic-facing checklist for pressure-testing operations after tissue grey-market warning letters, before a CID arrives. Read on Substack.
What Retaining Counsel Actually Needs from an Operator Expert
DOI: https://doi.org/10.5281/zenodo.23352293 (paper page)
2026-08-31
The designation is wasted if the role is fuzzy, the file is a theory, and the opinion is asked to outrun the operating record. Read on Substack.
The Permission Gap
DOI: https://doi.org/10.5281/zenodo.23352291 (paper page)
2026-08-16
Twelve states rewrote regenerative medicine law in eighteen months. Federal law did not move. Here is what that costs you. Read on Substack.
Sponsor kills ExoFlo perianal fistula trial after enrolling five patients
DOI: https://doi.org/10.5281/zenodo.23352289 (paper page)
2026-08-11
The sponsor terminated its ExoFlo trial in perianal fistula (NCT05836883) on August 11. Read on Substack.
The Hillman Letter
Weekly long-form essays on FDA regulatory strategy, frontier therapeutics, and capital decisions in healthcare. Publication home: thehillmanletter.substack.com.
The 351 vs 361 Question
Why most exosome programs choose the wrong FDA pathway and what that costs them. Published essay covering minimal manipulation, homologous use, and the BLA route.
Family Office Capital
Why patient capital fits FDA-regulated biotech better than venture timelines. Structuring investments around regulatory milestones rather than fundraising rounds.
Six Compliance Patterns
Six documentation patterns that show up before federal healthcare enforcement. Practical content for compliance officers and in-house counsel.
TOL Mechanism
Targeted Osmotic Lysis explainer. The mechanism behind TOL, an academic medical foundation partnership, and what it means for chemotherapy-free oncology.
Building Frontier From Dallas
The Dallas biotech ecosystem, the operator network, and why this is the place to build regulated healthcare today.
Where to find it.
Substack
The Hillman Letter weekly essays. thehillmanletter.substack.com
Long-form LinkedIn articles. linkedin.com/in/andrew-hillman-dallas
Press & podcasts
Coverage and podcast appearances logged at andrew-hillman.com/coverage.
Direct contact
For media or interview requests: [email protected].
Studies
Exosome and mesenchymal stem cell-derived extracellular vesicle products are not approved by the FDA for any indication. Targeted Osmotic Lysis is investigational and is not FDA-approved. The work referenced here describes published scientific literature. It does not describe an available treatment.
Authored studies with published titles and DOIs where issued. Last Part Standing is a book, listed separately.
- Structured review · DOI 10.5281/zenodo.21209815 (paper page)
- Narrative review · DOI 10.5281/zenodo.21047848 (paper page)
- Spine disc paper (Hillman, A. J., et al.) · DOI 10.5281/zenodo.20978822 (paper page)
- WJ-Derived MSC Exosomes · Academia.edu
- WJ Gold Standard · DOI 10.5281/zenodo.20974697 (paper page)
- Biologics Paradigm, 351(a) vs 361 · DOI 10.5281/zenodo.21142612 (paper page) · investigational, not FDA-approved
- WJ MSC Exosomes 351(a) CBER regulatory monograph · Zenodo DOI pending
- Mesenchymal Exosome Research: Top Studies by Body System · ResearchGate
- WJ MSC Exosome Clinical Study v3 · ResearchGate
- Targeted Osmotic Lysis TOL 2.0 · investigational · Academia.edu
Book
Last Part Standing
by Andrew Hillman, with Beverly Levine · Business & Entrepreneurship · Published July 2026
Last Part Standing is the account of three generations inside Midway Auto Supply, a Dallas family business founded in 1959 and closed in 2020. Part family history, part business post-mortem, it draws ten lessons on adapting to industry change, family conflict, financial discipline, and succession for entrepreneurs and family-business owners.
Available as Kindle eBook ($9.99) and Paperback ($12.99, 58 pages). Wikidata Q140403984. ISBN 979-8184773162.