Process Validation Plan

Vitalis Therapeutics Inc. — Process validation for VitaFlow (VTX-401): the three-stage lifecycle, critical process parameters and the attributes they drive, the 3-batch PPQ campaign scheduled Q1–Q2 2027, failure modes, and the evidence an inspector will examine before approval.

Validation stages

PPQ batches

Media fills

Critical parameters

Contents

You Cannot Test Quality Into a Product
The Three Stages
What Is Controlled Versus What Results
Qualifying Everything the Process Runs On
Process Qualification — the PPQ Campaign
Cleaning Validation
Personnel Qualification
What Can Go Wrong
Link to Pre-Approval Inspection
Sequence and Governance

1. You Cannot Test Quality Into a Product

This is the idea the whole discipline rests on, and it is worth stating plainly before any mechanics.

A finished batch is tested against specification before release. But testing samples a tiny fraction of the units, destroys what it samples, and can only detect what it is designed to look for. If a process is capable of producing a bad batch, release testing will eventually let one through — not because the testing is poor, but because sampling is sampling.

So quality is built in and then demonstrated. Validation is the evidence that the process — the equipment, the parameters, the people, the facility — reliably produces conforming product every time, so that release testing confirms an expected outcome rather than discovering an unknown one.

The practical consequence for a program manager: validation is not a quality-control activity that happens near the end. It is a body of evidence assembled across years, and it gates the filing independently of whether the drug works.

2. The Three Stages

Stage	Status	When	What it establishes
Stage 1 — Process Design	complete	2024–2026	Define the commercial process from development knowledge. Identify critical process parameters, establish the design space, and understand which variables move which quality attributes.
Stage 2 — Process Qualification	scheduled Q1–Q2 2027	PPQ	Demonstrate that the commercial-scale process, at the commercial site, with commercial equipment and trained personnel, reproducibly produces conforming product.
Stage 3 — Continued Process Verification	post-approval, ongoing	life of product	Confirm the process remains in a state of control. Statistical trending of parameters and attributes for as long as the product is marketed.

The lifecycle framing matters. An older model treated validation as an event — three batches, a report, done. The current model treats it as continuous: understand the process, demonstrate it, then keep confirming it for as long as the product is on the market.

Stage 3 is the one that surprises people from other industries. Validation does not conclude at launch. A commercial process is statistically trended for the life of the product, and drift detected five years after approval is a regulatory matter requiring investigation and potentially notification — not a manufacturing curiosity to be quietly corrected.

3. What Is Controlled Versus What Results

Two categories of variable, and confusing them is a common error.

A critical quality attribute (CQA) is a property the product must have — purity, assay, sterility. It is an outcome.
A critical process parameter (CPP) is something the manufacturer sets and holds — temperature, time, pH. It is an input.

Stage 1 establishes which inputs move which outcomes, and by how much. That relationship is the design space.

Critical process parameter	Control range	Attribute it drives	Note
Reaction temperature, acylation step	±2°C	Purity / related substances	Excursion drives impurity formation directly.
Reaction time, acylation step	±15 min	Purity / assay
pH, final formulation	±0.2 units	Aggregation, stability	The single most sensitive parameter in the drug product process.
Filtration flux rate	defined range	Sterility assurance, aggregation
Fill volume	±2%	Deliverable dose	Device performance depends on it.
Lyophilization not applicable	—	—	Aqueous solution product; no lyophilization step.

Read the pH row. A control range of ±0.2 units on final formulation pH sounds trivially tight until you consider what it protects: aggregation, which affects immunogenicity, which is a safety attribute of a parenteral peptide. Nobody sets a range that narrow for elegance. It is narrow because Stage 1 work showed that outside it, a quality attribute the patient depends on starts to move.

4. Qualifying Everything the Process Runs On

A validated process running on unqualified equipment is not validated. Qualification proceeds in a defined sequence, and each stage answers a different question.

Stage	Question	Evidence
DQ — Design Qualification	Is this equipment fit for the intended use?	Specification against user requirements, before purchase.
IQ — Installation Qualification	Was it installed as specified?	As-built drawings, materials of construction, calibration certificates, utility connections.
OQ — Operational Qualification	Does it operate across its intended range?	Challenge at the limits of each operating parameter, empty of product.
PQ — Performance Qualification	Does it perform with actual product under routine conditions?	Product or product-simulating runs at target conditions.

Utilities carry the same obligation and are easier to overlook: water for injection, clean steam, compressed gases and HVAC are all qualified, monitored and trended. A parenteral facility's environmental monitoring program is continuous rather than periodic.

OQ before PQ is not a formality. Operational qualification challenges equipment at the edges of its range, deliberately, without product. Performance qualification runs it at target with product. A program that compresses the two — qualifying at target only, because that is where the process will actually run — has no evidence about what happens when a parameter drifts, which is precisely the situation the design space at §3 is supposed to cover.

4. Process Qualification — the PPQ Campaign

Element	Design
Batches	3, at commercial scale
Site	Aldergate Biologics
Sampling	Heightened — sampling frequency and sample size above routine commercial release testing, to characterize within-batch and between-batch variability.
Acceptance	All CQAs within specification on every batch, plus statistical demonstration that between-batch variability is within the range predicted from Stage 1.
Aseptic process simulation	3 media fills

Aseptic process simulation. Growth medium substituted for product and filled under routine conditions; every unit incubated and inspected. Zero contaminated units permitted.

PPQ is a sequence, not a count. The requirement is three consecutive successful batches. A failure on batch two does not cost one batch — it costs the sequence. The investigation must complete, the root cause must be understood and addressed, and the campaign restarts at one.

That is why the RAID Log treats a PPQ failure as a schedule risk rather than a cost risk. The materials are replaceable. The calendar is not.

Note also the sampling design. PPQ batches are sampled far more heavily than routine commercial batches, because the purpose is different: routine testing asks is this batch acceptable, while PPQ asks is this process capable. Answering the second question requires enough data to characterize variability, not just to clear a limit.

6. Cleaning Validation

Shared equipment carries a residue risk, and cleaning is validated to the same standard as the manufacturing process itself.

Element	Standard
Acceptance limit	Derived from health-based exposure limits, not from an arbitrary “visually clean” threshold.
Recovery studies	Demonstrating the sampling method actually recovers residue from the surface being sampled.
Sampling	Swab and rinse, at worst-case locations identified by equipment mapping.
Hold times	Both dirty-hold and clean-hold periods validated — equipment left clean for a month is not self-evidently still clean.
Campaign length	How many consecutive batches before a full clean is required.

Worst-case location is the concept worth carrying. Cleaning is not validated by sampling where residue is easiest to reach. It is validated at the points identified as hardest to clean — dead legs, gasket seats, transfer line low points. A cleaning validation that sampled convenient locations has demonstrated that convenient locations get clean.

7. Personnel Qualification

PPQ demonstrates a process as operated, which makes the operators part of what is being qualified.

Trained and documented on every procedure they execute, before they execute it.
Aseptic gowning qualification for anyone entering the classified area, re-qualified periodically.
Media fill participation — each operator who works on aseptic processing participates in a media fill.
Consistency across the PPQ sequence. Material changes in the operating team mid-campaign undermine the claim that the qualified process is the commercial process.

This is why the CRO staff-turnover KPI in the CRO Oversight Plan is not a soft metric. In clinical operations, turnover costs relationships and start-up speed. In manufacturing it costs qualification — a departed operator's training record does not transfer, and a replacement is not qualified until they demonstrably are.

5. What Can Go Wrong

Failure mode	Type	Consequence
A PPQ batch fails	Schedule	PPQ is three consecutive successful batches. A failure does not cost one batch; it costs the sequence, plus investigation time before the next attempt can start.
Method transfer not closed before PPQ	Sequence	PPQ batches must be tested with qualified methods at the testing site. GC-01 gates PPQ start, not just registration batch three.
Between-batch variability exceeds the Stage 1 prediction	Technical	Passing specification is necessary but not sufficient. Three batches that all pass while varying more than the design space predicted indicate the process is not understood.
Media fill contamination	Quality	A single contaminated unit invalidates the simulation and triggers a full investigation of the aseptic process.
Personnel or equipment change between batches	Compliance	PPQ demonstrates a process as operated. Material changes mid-sequence undermine the claim that the qualified process is the commercial process.

The second row is this program's live exposure. PPQ batches must be tested using qualified methods at the testing site. The purity method is not yet re-qualified at Aldergate, which means GC-01 gates the start of PPQ — not merely the third registration batch, as the headline reading of the condition suggests.

That is a dependency worth surfacing precisely, because the two consequences have different schedule weights. A delayed registration batch costs weeks. A delayed PPQ start compresses a three-batch consecutive campaign against a fixed filing date, and PPQ has no float in it by design.

The third row is subtler and worth understanding. Three batches can each pass every specification and still constitute a failed qualification, if the variability between them exceeds what Stage 1 predicted. Passing means the product was acceptable. Qualifying means the process is understood. A process that produces conforming product for reasons the manufacturer cannot explain has not been validated — it has been lucky three times.

6. Link to Pre-Approval Inspection

Validation evidence is the substance of what an inspector examines at the pre-approval inspection, scheduled ahead of the October 2029 action date.

Evidence	What the inspector is testing
PPQ protocol and reports	Reviewed at inspection as evidence the process was qualified before commercial supply.
Deviation and investigation records	Inspectors read investigations more closely than successes. An investigation with a weak root cause is worse than the deviation.
Batch records for PPQ batches	Contemporaneous, complete, and signed. Retrospective completion is a data integrity finding.
Equipment and utility qualification	IQ/OQ/PQ documentation for everything in the process train.
Personnel training records	That the people who ran the batches were qualified to.
Media fill records	Aseptic process capability.

Inspectors read investigations more closely than successes, and this is the single most useful thing to know about inspection. A deviation with a thorough investigation, a defensible root cause and effective corrective action demonstrates a functioning quality system. A deviation with a thin investigation and a root cause of “operator error” demonstrates the opposite — and the second finding is far more damaging than the deviation itself ever was.

The corollary: a site with no deviations recorded across a PPQ campaign is not reassuring. It is a site whose recording practices should be examined.

7. Sequence and Governance

Validation sits inside a dependency chain the program has to hold visible.

Step	Depends on	Feeds
Method re-qualification (GC-01)	Aldergate laboratory	Registration batch 3 and PPQ start
PPQ campaign	Qualified methods; commercial equipment released	Process validation report
Media fills	Aseptic facility qualified	Sterility assurance case
Process validation report	PPQ complete	NDA Module 3
Pre-approval inspection	Validation evidence available on site	Approval

Five links, three organizations, one action date. DEP-04 in the RAID Log records the binding constraint: process validation must complete before the pre-approval inspection, and the inspection must close before approval.

What the program manager actually does here. Not validation — that is Technical Operations and Quality Assurance. The contribution is holding the chain visible, refusing to let GC-01 be closed on two methods when the third gates two downstream workstreams, and making sure the Development Committee understands that a PPQ slip and an enrolment slip are not comparable risks. Enrolment has recovery levers. A consecutive-batch campaign against a fixed date does not.