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Essays · The Hillman Letter

Operator notes from inside regulated medicine.

Essays that walk through FDA regulatory strategy, frontier therapeutics, family office capital, and healthcare compliance. Thirty years of operating experience, written so you can read each one in twenty minutes. Seven essays published. New essays weekly.

The Hillman Letter

The Hillman Letter · Latest · 2026-09-21

The R3 Medical Warning Letter Is a Pattern, Not a Mood

What operators should extract from FDA warning-letter patterns in regenerative clinics.

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The Hillman Letter · 2026-09-14

The Same Surgical Procedure Loophole Is Closed. Here Is What the Cell Surgical Network Injunction Means for Everyone Building a Cell or Exosome Product.

Eight years, one reversal, and a nine-page order that ends the argument.

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The Hillman Letter · 2026-08-16

The Permission Gap

Twelve states rewrote regenerative medicine law in eighteen months. Federal law did not move. Here is what that costs you.

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The Hillman Letter · 2026-08-11

Direct Biologics kills ExoFlo perianal fistula trial after enrolling five patients

Direct Biologics terminated its ExoFlo trial in perianal fistula (NCT05836883) on August 11.

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The Hillman Letter · 2026-07-27

The CMC chasm. Why most biotech IND submissions fail at chemistry, not biology.

The biology is usually right. The chemistry, manufacturing, and controls package is where most IND submissions fail.

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Full archive on thehillmanletter.substack.com.

Essay · 2026-06-11 · 1450 words

The NextMed Settlement Is a Roadmap. Read It Before You Build the Next Telehealth Brand.

The FTC just handed the telehealth industry an inspection checklist.

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Essay · 2026-06-11 · 1380 words

The Specific Pattern That Killed Five Biotech Programs I Personally Watched

The pattern was the same across five programs. In case you are running one of the next ones.

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Essay · 2026-06-10 · 1410 words

Why Dallas Is Quietly Becoming the Right Place to Build FDA-Regulated Biotech

The Dallas-Fort Worth biotech ecosystem has been compounding for three decades.

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Essay · 2026-06-09 · 1320 words

The 351 vs 361 Decision That Kills Most Exosome Programs

Why most exosome programs pick the wrong FDA pathway, and what the BLA route actually demands.

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Exosome and mesenchymal stem cell-derived extracellular vesicle products are not approved by the FDA for any indication. References here describe investment focus and published scientific literature. They do not describe an available treatment.
Essay · 2026-06-08 · 1280 words

Why Family Office Capital Fits FDA-Regulated Biotech Better Than Venture Money

A ten-year venture fund has to return capital on a schedule. The FDA does not care about your schedule.

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Essay · 2026-06-07 · 1380 words

The Six Documentation Patterns That Show Up Before Federal Healthcare Enforcement

Every enforcement action I have served on involved a pattern visible eighteen to thirty-six months before.

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Essay · 2026-06-12 · 1480 words

What Thirty Years of Operating in FDA-Regulated Healthcare Actually Taught Me

Five lessons I would tell my younger self if I could.

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