There’s no shortage of opinions on Person-in-Plant programs in the sponsor-CMO space. Sponsors see them as a necessary oversight tool, but CMOs often experience them as a sign that trust has broken down. PIP programs produce such varied outcomes because the same mechanism that strengthens a relationship in one context can erode it in another. What you get out of your PIP program is determined by how deliberately you design and deploy it. Quality leaders at Thermo Fisher/Patheon, Fujifilm Diosynth, Sentrx, and Boehringer Ingelheim have worked through this question to construct a practical framework for enacting a PIP program the right way.  

Start With Why

Before getting into mechanics, it’s worth noting the reason PIP programs exist in the first place. The connection back to the patient, understanding whose medicine is being made, and what it means to get it right is foundational to the kind of culture where oversight tools do their job.

That framing has practical implications. Sponsors are often closer to the patient story than the CMO teams manufacturing the product. They know the disease, the patient population, and the clinical journey that brought the molecule to this point. Bringing those stories into the facility and sharing them with the people on the floor gives the work meaning that pure process execution cannot supply on its own. A PIP deployed by a sponsor who does this actively produces something different than one deployed by a sponsor focused only on compliance. The commitment to quality is already present on the CMO side, but sponsors who connect that commitment to the patient story reinforce it in ways that compliance oversight alone cannot.

When a Person-in-Plant Program Supports Inspection Readiness

The situations where Person-in-Plant programs consistently add value share a common characteristic: they are time-bounded, purposeful, and additive to an existing governance structure.

Program startup and first batches is the clearest case. Having a sponsor representative present when a new product is first manufactured allows for real-time knowledge sharing, catching process gaps before they become deviations, and building interpersonal relationships that make quality conversations easier down the line.

Pre-approval inspections are also a high-value window, both during preparation and during the inspection itself. When a sponsor and CMO present to an FDA investigator as a genuine team, with the CMO leading and the sponsor available for product-specific questions, the result is the kind of relationship FDA has recognized as among the strongest it has seen in a PAI setting.

Escalated governance situations are another legitimate use. When a program has entered a heightened oversight status and a greater level of sponsor visibility is needed, a time-bound PIP with clear objectives and exit criteria can accelerate remediation and rebuild confidence. Used in this way, the PIP is a tool for getting a relationship back to a healthy place.

When a Person-in-Plant Program Undermines GMP Compliance

For all the benefits of a PIP program, there are some risks that are worth noting. A PIP deployed as permanent, open-ended surveillance signals that the sponsor doesn't trust the CMO's quality system, and that will inevitably impact the relationship (regardless of intent). If the CMO team experiences the constant presence as policing rather than collaboration, the relationship that makes the whole arrangement work will fall apart.

There’s another dimension of this that often goes unacknowledged. When a CMO serves more than one customer at the same facility, a sponsor representative with a permanent presence restricts what the CMO can openly share, since learnings from one client's program cannot freely flow to another's. The knowledge-sharing that makes a trusted CMO relationship genuinely valuable becomes harder to deliver when one sponsor is always in the room, and the PIP intended to deepen the relationship can unintendedly sabotage it.

Over-familiarity also creates a parallel risk. A PIP representative embedded long enough to build close relationships with the site team may lose the objective perspective that makes their presence useful, leaving the sponsor with someone is no longer providing independent oversight. The value of the program depends on that independence being maintained, and it can quietly erode if the role has no defined scope or endpoint.

There is also a regulatory dimension to consider. When a sponsor representative effectively directs site quality decisions, shaping deviation write-ups or overriding CMO quality judgments, it creates the quality unit independence problem that FDA and MHRA have flagged. Oversight and control are different things, and that distinction is important to regulators.

The Governance Foundation FDA Inspection Readiness Actually Requires

The most important point to all of this is that a PIP only functions well when the broader governance structure is already healthy. Regular joint quality reviews, defined escalation paths, shared performance metrics, and a quality agreement that both parties use as a working document all empower a PIP to add value. Deploying one into a relationship that lacks this foundation creates the appearance of oversight while ignoring the underlying problems. If a sponsor is considering a PIP because governance has broken down, rebuilding that governance structure first would be much more valuable intervention in the long run.

For a fuller treatment of Person-in-Plant best practices, governance frameworks, the accountability dynamics around deviation write-ups, and how the broader sponsor-CMO relationship holds up under inspection pressure, download our white paper: The New Rules of CMO-Sponsor Collaboration: Inspection Trends, Shared Risk, and the Path to Predictive Quality.