Stopped Production, Now What? The Restart Playbook After an FDA Warning Letter

On 13 October 2026 the United States Food and Drug Administration posted a warning letter that should make every contract manufacturer and over-the-counter drug maker pause. Silgan Dispensing Systems, through its Silgan Unicep Packaging facility in Spokane, Washington, had already done what many firms fear most. It had stopped making drugs. After a July teleconference with FDA, a customer recalled affected product, the company committed to suspend all drug production at the site, and the agency told the firm to give notice before it ever resumes.

A production stop is not the end of a compliance problem. It is the start of the hardest phase: proving to a regulator that the conditions that caused the failure are gone, and that the quality system can be trusted again. That proof has a shape. This article walks through the restart playbook, using the Silgan letter as a live example, and shows Canadian exporters how to build the evidence package FDA expects before a single batch moves again.

What a production stop after a warning letter actually means

A production stop is a voluntary or committed halt to manufacturing while a firm fixes the conditions that made its product adulterated. It matters because the stop itself does not clear the warning letter. The findings stay open until the firm proves, with evidence, that each root cause is corrected and that the corrections hold. What companies should do is treat the restart as a regulated project with its own plan, owner, milestones and sign-off, not as a switch to flip once the backlog of paperwork clears.

In the Silgan case the facility obtained out-of-specification microbiological results for components in November 2025, averaged yeast and mould counts to reach a passing number, and then revised its sampling plan to permit that averaging. FDA states the averaging is not consistent with the United States Pharmacopeia <61> method. The affected lots were released and used in manufacturing, and a customer later began a Class I recall for potential fungal contamination. A single mishandled result cascaded into released product, a recall and a shutdown.

The Silgan sequence: how one teleconference became a full shutdown

The timeline shows how quickly a data-handling shortcut becomes an existential event. It matters because each step narrowed the firm's options. What companies should do is recognise the decision points, because the same pattern repeats across FDA enforcement.

When	What happened	Why it mattered
November 2025	OOS yeast and mould results on components; counts averaged to pass; sampling plan revised to allow averaging	A failing result was turned into a passing one, against USP <61>
26 March to 2 April 2026	FDA inspects the Spokane facility	The averaging, missing cleaning validation and gaps in environmental monitoring surface
July 2026	FDA teleconference; agency recommends a recall; website claims reviewed	A customer initiates a Class I recall; products treated as unapproved new drugs
22 July 2026	Recall recommended during the teleconference	Distributed lots pulled from the US market
5 October 2026	Warning letter issued; firm has committed to suspend all drug production	FDA requires notice before any restart and recommends an independent consultant
13 October 2026	Warning letter posted publicly	Reputation and customer confidence now in play

The findings behind the shutdown, and what each one demands

FDA grouped its findings under two core CGMP rules, with specific sub-failures under the quality unit. They matter because a restart plan has to answer every one of them, not just the headline. What companies should do is map each citation to a corrective action with an owner and an evidence trail.

Out-of-specification investigation (21 CFR 211.192)

The firm averaged microbiological counts to pass and limited its retrospective review to documented OOS events. FDA found the investigation inadequate, noted there was no cleaning procedure or cleaning validation for a production line, and observed that yeast and mould testing was missing from environmental monitoring. Averaging a microbial count to reach a specification is one of the most reliably cited data-integrity failures in FDA letters. Our deeper treatment of this rule is in the investigation FDA cites first.

Quality unit responsibilities (21 CFR 211.22)

FDA concluded the quality unit did not adequately oversee OTC drug manufacturing, and that deficiencies persisted for multiple years. The quality unit is the one function FDA holds accountable when a system fails. When it cannot show it controlled release, investigations and change, every other finding compounds.

Supplier test validation (21 CFR 211.84(d)(2))

The firm did not validate and establish the reliability of its component supplier's test analyses at appropriate intervals. A certificate of analysis is only usable if the receiving firm periodically confirms the supplier's results against its own testing. This is the same lesson as your contract lab's warning letter is your problem, and it is why a supplier qualification programme that survives an inspection needs defined re-validation intervals.

Stability and annual product review (211.166(a) and 211.180(e))

FDA noted no stability study reports since 2020 and annual product reviews not completed for several products since 2024. Both are routine, foundational records. Their absence tells an inspector the quality system was not running. Building the review FDA expects is covered in annual product quality review (APQR).

Unapproved new drug and adulteration charges

In July 2026 FDA reviewed the product website and labelling and concluded the products are drugs under section 201(g)(1) of the Federal Food, Drug, and Cosmetic Act and new drugs under section 201(p), because they are not generally recognised as safe and effective for their labelled uses. That makes them unapproved new drugs under section 505(a), and introducing them into interstate commerce violates sections 301(d) and 505(a). The letter also cites adulteration under section 501(a)(2)(B). Marketing copy turned a CGMP problem into a drug-approval problem. The same trap is detailed in FDA's unapproved new drug letters.

Your restart playbook: the evidence package FDA expects before you resume

The restart package is the documented set of corrections, verifications and controls a firm assembles to show it can manufacture safely again. It matters because FDA told Silgan to notify the office before resuming any drug operations, which means the agency decides when restart is credible. What companies should do is build the package in a defined order, with evidence for each step, before asking to resume.

A credible restart package includes, at minimum:

Root cause analysis for every finding. Not a restatement of the observation, but the systemic reason it happened, confirmed with data.
A CAPA plan with owners, due dates and effectiveness checks. FDA specifically asks firms to evaluate the completion and efficacy of CAPA, so an effectiveness review is part of the package, not an afterthought.
A retrospective review that is not limited to documented OOS events. Silgan's response was found inadequate precisely because it stopped at recorded events. Look for the same failure mode across products, lines and time.
Cleaning procedures and validated cleaning. Each production line needs a written cleaning procedure and documented cleaning validation before it restarts.
A rebuilt environmental monitoring programme. Add the organisms you missed. For Silgan that meant yeast and mould. Define alert and action limits and trend the data.
Supplier analysis re-validation. Confirm each component supplier's test results against your own testing at a defined interval, and write the interval into the quality agreement.
A functioning stability programme. Put every marketed product on a written stability protocol and generate current reports.
Completed annual product reviews. Close the backlog and set a schedule that will not fall behind again.
A corrected labelling and claims review. Remove or substantiate any claim that makes the product a drug, and reconcile the website with the regulatory status of each product.
A written restart protocol and notification. Define the criteria that must be met before the first batch, and notify FDA before resuming, as the letter requires.

The independent consultant under 21 CFR 211.34: what the role really is

FDA recommends engaging a consultant qualified under 21 CFR 211.34 and a comprehensive six-system audit. It matters because the agency is signalling that the firm's own assurances are no longer enough on their own. What companies should do is bring in a qualified, independent reviewer early, not as a rubber stamp, but to test the restart package the way FDA will.

Under 21 CFR 211.34, a consultant advising on compliance must have enough education, training and experience, or a combination of these, to do the job, and the firm must keep records of the consultant's qualifications. The six-system model, the quality system plus the production, facilities and equipment, laboratory controls, materials, and packaging and labelling systems, is the framework FDA inspectors use. A restart audit built on those six systems gives the agency a map it recognises. A strong engagement also evaluates whether CAPA actually worked, because effectiveness, not activity, is what the letter asks for.

Why this matters for Canadian exporters

Canadian firms that ship drugs, OTC products or natural health products into the United States are inspected against the same CGMP rules. It matters because an FDA warning letter and a production stop can close the US market overnight, and Health Canada may ask about the same quality system. What companies should do is run their own mock restart before an inspector ever forces one.

A Canadian exporter facing the Silgan findings would also need to satisfy Health Canada's Good Manufacturing Practices guide GUI-0001, which sets parallel expectations for investigations, stability, supplier controls and product quality review. The transparency trend matters too: FDA has signalled it will publish more inspection outcomes, as we explain in FDA plans to publish Form 483s. A warning letter that names your firm is now a permanent, searchable record your customers and partners will find.

Restart readiness compliance checklist

Use this checklist to test whether your restart package is ready before you contact FDA.

Every warning letter finding mapped to a documented root cause
CAPA plan complete, with owners, due dates and an effectiveness review
Retrospective review extended beyond recorded OOS events across products and lines
Written cleaning procedures and completed cleaning validation for each line
Environmental monitoring programme rebuilt with the missing organisms and defined limits
Supplier test analyses re-validated at a defined interval, written into quality agreements
Stability protocols in place and current reports generated for all marketed products
Annual product reviews backlog cleared and a schedule set
Labelling and website claims reconciled with each product's regulatory status
Independent six-system audit under 21 CFR 211.34 completed, with qualifications on file
Written restart protocol defining go or no-go criteria, and FDA notified before resuming

Common mistakes that keep a firm shut down

Fixing observations, not systems. Correcting the specific lots FDA named while leaving the sampling plan, the quality unit gap or the training failure in place.
A CAPA plan with no effectiveness check. FDA asks whether CAPA worked. A plan that lists actions but never verifies them reads as incomplete.
Restarting before notifying FDA. The Silgan letter is explicit. Resuming without notice turns a compliance problem into a worse one.
Treating the consultant as a signature. A six-system audit that finds nothing is not reassuring. It looks like a package built to pass rather than to fix.
Ignoring the marketing claims. A website that makes drug claims can keep a product in unapproved new drug territory no matter how clean the plant becomes.
Leaving stability and annual reviews for later. These foundational records are often the first thing an inspector asks for and the clearest sign a quality system is not running.

Frequently asked questions

Does a production stop clear an FDA warning letter?

No. A production stop halts the ongoing violation, but the findings stay open until the firm proves each root cause is corrected and the corrections are effective. FDA decides when the compliance status is resolved, often after a follow-up inspection.

Do we have to tell FDA before we restart?

In the Silgan letter FDA directs the firm to notify the office before resuming any manufacturing operations regulated under the Act. When a letter contains that instruction, resuming without notice is itself a serious problem. Treat notification as a required step in the restart plan.

What does a consultant qualified under 21 CFR 211.34 do?

Under 21 CFR 211.34, a qualified consultant advises on CGMP compliance and must have the education, training and experience to do so, with records of those qualifications kept by the firm. In a restart, the consultant typically performs a six-system audit and verifies that CAPA closed the root causes.

What is a six-system audit?

It is an audit built on FDA's six systems: the quality system, plus production, facilities and equipment, laboratory controls, materials, and packaging and labelling. It is the same framework FDA inspectors use, which is why it is the right structure for a restart review.

Why can averaging a microbial result trigger all of this?

Averaging an out-of-specification microbial count to reach a passing number is a data-integrity failure. It hides a real result, releases product that should have been held, and signals that the quality unit did not control release. FDA treats it as a systemic problem, not a one-off error.

We are a Canadian firm. Does a US warning letter affect us at home?

It can. Health Canada expects the same controls under GUI-0001, a public FDA letter is visible to your customers and partners, and foreign regulators share inspection information. A problem that closes the US market rarely stays contained to the US market.

How MFLRC can help

MF License and Regulatory Consultants helps manufacturers in Canada, the United States and Europe respond to FDA 483s and warning letters and rebuild the quality systems behind them. Our work includes gap assessments against FDA CGMP and Health Canada GUI-0001, root cause analysis and CAPA development, six-system audits and inspection readiness reviews, supplier qualification and certificate of analysis verification programmes, stability and annual product quality review builds, standard operating procedure development, and independent reviewer support under 21 CFR 211.34. We help firms design a restart plan an inspector will accept, then test it before FDA does.

If you are preparing a response or planning a restart, we can run a remediation readiness review and tell you honestly whether your evidence package is ready. Explore our audit services, regulatory affairs, licensing and import and export support, and quality control services.

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Conclusion

The Silgan letter is a reminder that the dangerous moment is not the inspection, it is everything that follows. A production stop buys time, but it does not buy trust. Trust is rebuilt through a documented restart plan, root cause analysis that reaches the system, CAPA that is proven to work, an independent six-system audit, and a notification to FDA before the first batch moves. Firms that build that package in order, and that are willing to hear an honest reviewer say it is not ready yet, are the ones that come back. Those that patch the named observations and hope tend to stay shut down.