Biologics and Cell & Gene Therapy: Why CBER Warning Letters Are Growing Fastest (2026)

Part of: FDA Enforcement by Industry

TL;DR

CBER-regulated biologics, including cell and gene therapy manufacturers, represent a smaller share of total FDA Warning Letter volume than CDER or CDRH, but industry watchers describe the category as an emerging enforcement target as the sector scales.

A June 2026 CBER letter to Genzyme Ireland Limited, a Sanofi subsidiary, cited a quality control unit that failed to enforce CGMP and lab records showing certain tests repeated up to 11 times without documentation of why.

A separate March 2026 warning letter to Novo Nordisk over Ozempic and Wegovy safety reporting illustrates a distinct enforcement category within the same general regulatory neighborhood — a pharmacovigilance and adverse-event-reporting action rather than a manufacturing-CGMP citation, naming specific internal case numbers including a stroke, a suicide, and unreported deaths.

The Novo Nordisk example shows that even within a single company, different products and different compliance functions can draw fundamentally different citation types from different parts of FDA's regulatory apparatus.

Why biologics enforcement deserves separate treatment

CBER's regulatory territory — biologics, including increasingly complex cell and gene therapy products — is smaller in total Warning Letter volume than CDER's drug enforcement or CDRH's device enforcement, but the products it regulates are, in many cases, manufactured using more novel and more technically complex processes than conventional small-molecule drugs. That complexity is part of why industry observers treat CBER as an emerging enforcement area to watch as the cell and gene therapy sector scales: newer, less standardized manufacturing processes create more surface area for CGMP-type findings than a mature small-molecule manufacturing line typically does.

The Genzyme Ireland example

A June 2026 CBER letter to Genzyme Ireland Limited, a subsidiary of Sanofi, cited a quality control unit that failed to enforce CGMP, along with lab records showing certain tests repeated up to 11 times without documented justification for the repetition, and deviations that were cancelled without a documented root-cause investigation (Argus HQ, "Genzyme Ireland Limited FDA Warning Letter CBER 26-728681"). The specific pattern here — tests repeated up to 11 times without documentation of why — reads as a data-integrity-adjacent finding: not necessarily fabrication in the way the Huons Co. case (covered in the companion Warning Letter anatomy content) documents, but a records-and-justification gap that undermines confidence in which of the 11 repeated test results the company actually relied on and why. This kind of finding sits squarely within the quality-control-unit-authority category that also dominates CDER's most-cited drug provision (21 CFR 211.22), even though CBER operates under its own biologics-specific framework rather than citing that exact CDER provision.

The Novo Nordisk example: a different enforcement category entirely

A March 2026 warning letter to Novo Nordisk over Ozempic and Wegovy safety reporting illustrates a category of enforcement action that's easy to conflate with manufacturing CGMP citations but is actually structurally distinct: a pharmacovigilance and adverse-event-reporting action. This letter names specific internal case numbers — including a stroke, a suicide, and unreported deaths — where the company's own procedures blocked required 15-day adverse event reports from reaching FDA (Argus HQ, "Why did the FDA send Novo Nordisk a warning letter over Ozempic and Wegovy safety reporting?"). This is a CBER/CDER-adjacent action rather than a straightforward CBER manufacturing citation — Ozempic and Wegovy are CDER-regulated drug products (semaglutide), and the letter's substance concerns post-market safety-reporting obligations rather than manufacturing process controls, a different regulatory function than the CGMP-focused Genzyme Ireland letter above even though both fall generally within the biologics-and-drug-safety regulatory neighborhood this spoke covers.

Why one company can face fundamentally different citation types on different products

The Novo Nordisk example is worth dwelling on specifically because it demonstrates something the pillar's broader "what this means" section states as a general principle: one company can face multiple, unrelated enforcement tracks at once. Novo Nordisk's Ozempic and Wegovy safety-reporting letter and a manufacturing-CGMP letter (had the company received one) would represent entirely different regulatory functions — one addressing what the company tells FDA after a product is on the market and problems emerge, the other addressing how the company makes the product in the first place. A compliance team at a large biologics or biologics-adjacent company needs separate monitoring and separate response infrastructure for pharmacovigilance obligations and manufacturing CGMP obligations, because a clean record on one says nothing about exposure on the other, as the Novo Nordisk case demonstrates directly.

What this means for biologics and cell/gene therapy manufacturers

Treat CBER manufacturing citations as data-integrity-adjacent even when they don't use that exact language. The Genzyme Ireland pattern (tests repeated without documented justification) reflects the same underlying concern — an unreliable or unverifiable quality record — that drives data integrity findings elsewhere in FDA enforcement.
Pharmacovigilance and manufacturing CGMP are separate compliance functions requiring separate monitoring. The Novo Nordisk example shows a company can be cited on post-market safety reporting independent of, and by a different enforcement logic than, any manufacturing-process finding.
Newer, more technically complex manufacturing processes (cell and gene therapy specifically) carry more inherent surface area for CGMP-type findings. Treat process standardization and documentation as a growing compliance priority as this sector scales, not a settled, mature-industry practice.
A biologics company's overall enforcement risk isn't captured by tracking CBER citations alone. Depending on the specific products involved, a company may face CDER-adjacent pharmacovigilance exposure, CBER manufacturing exposure, or both simultaneously.

Sources

Argus HQ is informational only. Summaries are AI-assisted and may contain errors, misclassifications, or omissions. The underlying FDA Warning Letters are public records; always verify against the original source before regulatory decisions. Not legal, financial, or medical advice.

Biologics and Cell & Gene Therapy: Why CBER Warning Letters Are Growing Fastest