A practical decision framework for pharma, biotech and diagnostic teams managing biomarker-driven drug development, investigational IVDs and companion diagnostics

Choosing a CRO for a precision-medicine clinical trial is fundamentally different from choosing a conventional pharmaceutical CRO. When an investigational in vitro diagnostic (IVD) or companion diagnostic (CDx) is used to select patients, determine eligibility, stratify treatment, or support a therapeutic claim, the diagnostic can become a regulated development program running in parallel with the medicinal product.

The right partner therefore needs to understand not only clinical operations, but also IVD regulation, assay performance, biomarker strategy, specimen workflows, regulatory submissions, sponsor responsibilities, laboratory oversight and drug-diagnostic co-development.

The core selection question

Which CRO can manage the regulatory, scientific and operational dependencies between the drug, the biomarker assay and the clinical trial without creating gaps between them?

What should you look for in an IVD/CDx CRO?

IVD/CDx-specific regulatory strategy
Drug-diagnostic co-development experience
Analytical and clinical performance understanding
IVDR and FDA investigational-device pathways
ISO 20916-aligned clinical performance study execution
Testing-site and laboratory oversight
Multicountry regulatory and ethics coordination
Clear allocation of sponsor, diagnostic manufacturer, laboratory and CRO responsibilities

For global programs, the CRO should also understand how the same assay may occupy very different regulatory positions in the EU, UK and US. The strongest provider is rarely the organization offering the longest generic service list. It is the one that can show how diagnostic development and therapeutic development remain synchronized from protocol design through regulatory submission.

Why precision-medicine trials create a different CRO problem

In a conventional pharmaceutical study, the CRO may primarily focus on activities such as site activation, monitoring, data management, pharmacovigilance and trial management. Precision-medicine studies introduce another layer.

A biomarker assay may determine:

whether a patient enters the trial;
which treatment arm a patient enters;
whether treatment continues;
how a therapeutic population is defined;
whether a drug ultimately requires an approved companion diagnostic.

FDA defines a companion diagnostic as a device that provides information essential to the safe and effective use of a corresponding therapeutic product. FDA also states that, in most circumstances, the therapeutic product and its corresponding companion diagnostic should reach approval or clearance contemporaneously.

This means the assay strategy cannot be treated as an isolated laboratory activity. A delay or deficiency in the diagnostic workstream can affect patient enrollment, therapeutic endpoints, regulatory interpretation, drug labeling and market authorization.

First determine what the assay actually is

One of the earliest tests of a potential CRO is whether the team asks the right questions about the assay before proposing a study. Not every biomarker assay used in a drug trial is automatically a companion diagnostic.

Questions should include:

What is the assay’s intended purpose?
Is the result used prospectively?
Does it determine eligibility?
Does it influence treatment allocation?
Is it exploratory, enrichment, stratification or predictive?
Is the assay intended ultimately to become a commercial CDx?
Is it already CE marked or FDA authorized?
Is it being used within or outside its existing intended purpose?
Is the clinical trial assay the final commercial assay?
Will bridging be required later?
Who is the legal manufacturer?
Who is the performance-study sponsor?

Under the EU IVDR, a companion diagnostic is specifically an IVD essential for the safe and effective use of a corresponding medicinal product, including identifying patients most likely to benefit or those at increased risk of serious adverse reactions.

Selection signal The CRO should be capable of distinguishing between a biomarker assay used in clinical development and an IVD with a genuine CDx intended purpose. If a potential provider calls every biomarker assay a CDx, that is a warning sign.

1. Evaluate regulatory capability before clinical-operations capacity

Many CRO selection exercises begin with countries, sites, recruitment, CRAs and timelines. For an IVD/CDx program, regulatory architecture should come first.

A capable CRO should be able to map: device status -> intended purpose -> study design -> regulatory pathway -> documentation -> competent authorities/IRBs/ethics committees -> operational consequences.

European Union

The IVDR regulates performance studies of IVDs, while a medicinal-product clinical trial is governed separately under the Clinical Trials Regulation. MDCG 2025-5 explicitly recognizes combined studies involving simultaneous investigation of a medicinal product and an IVD.

That creates a practical challenge: one clinical program, but potentially two regulatory systems. A CRO supporting a combined drug/CDx study should therefore understand both the clinical-trial workstream and the IVDR performance-study workstream – and, crucially, where the two interact.

For CDx performance studies, the applicable route depends on factors such as CE-marking status, intended purpose, study design and whether only leftover samples are used. These distinctions can materially affect study planning.

United States

FDA states that therapeutic-product trials using investigational IVDs may be subject to the Investigational Device Exemption framework in addition to the IND framework. For significant-risk investigational devices, FDA approval of an IDE may be required before the clinical investigation begins.

A CRO should therefore be able to discuss:

investigational IVD status;
significant-risk versus non-significant-risk considerations;
IDE strategy;
Q-Submission interactions;
analytical readiness before prospective clinical use;
PMA/CDx development planning;
therapeutic and diagnostic timeline alignment.

A provider that says simply “we know FDA” or “we know IVDR” has not demonstrated enough. Ask them to map your exact assay and study.

2. Look for genuine drug-diagnostic co-development experience

This may be the most important differentiator. Precision-medicine programs often involve several organizations simultaneously:

Pharma sponsor
Diagnostic manufacturer
Central or specialty laboratory
IVD/CDx CRO
Drug CRO
Clinical sites
Regulatory authorities / ethics committees
Notified Body / medicines authority

Problems tend to arise at the interfaces between them. For example:

Who owns the IVD protocol language?
Who maintains the Investigator’s Brochure for the diagnostic?
Who evaluates device deficiencies?
Who determines whether an assay change constitutes a substantial modification?
Who communicates assay changes to clinical sites?
Who controls analytical-validation documentation?
Who coordinates safety reporting?
Who assesses whether a new reagent lot or software version affects the study?
Who owns specimen-chain deviations?
Who manages device accountability?
Who ensures the drug protocol and IVD performance-study documentation remain aligned?

If nobody owns these interfaces, the sponsor effectively becomes the integration layer. A specialist CRO should reduce that burden.

3. Ask for a responsibility matrix before awarding the work

One of the most useful CRO-selection exercises is to request a preliminary responsibility matrix. The exact allocation will vary by program; what matters is whether the provider understands that responsibilities must be explicitly allocated.

Activity	Pharma Sponsor	Dx Manufacturer	IVD/CDx CRO	Laboratory	Drug CRO
Biomarker strategy
Intended-purpose definition
Analytical-validation evidence
Clinical Performance Study Plan
IVDR/FDA pathway assessment
Regulatory submissions
Site / laboratory qualification
Training and specimen logistics
Monitoring / device accountability
Device deficiencies / safety
Data management / reporting
Assay change control

Ambiguity at proposal stage often becomes operational friction later.

4. Test whether the CRO understands analytical readiness

A clinical trial cannot compensate for an inadequately characterized assay. Before a biomarker assay influences patient-management decisions, sponsors should understand whether the assay is sufficiently analytically robust for the proposed use.

A qualified CRO should be capable of discussing:

precision and reproducibility;
analytical sensitivity and specificity;
cut-off determination;
limit of detection;
interfering substances;
specimen stability;
reagent stability;
site-to-site and instrument variability;
pre-analytical factors;
invalid-result handling.

Your CRO does not necessarily need to perform every analytical study itself. But it must understand the evidence sufficiently well to determine whether the assay is ready for clinical deployment.

5. Look beyond ‘site monitoring’

IVD/CDx monitoring is not simply pharmaceutical monitoring with a diagnostic checklist added. The monitor may need to understand:

device handling and accountability;
sample collection and specimen preparation;
storage and shipping conditions;
assay workflow and operator training;
instrument requirements and reagent lots;
quality controls, invalid runs and repeat testing;
deviations, device deficiencies and traceability.

In precision-medicine trials, seemingly small pre-analytical differences can affect biomarker results. Site and laboratory qualification are therefore especially important. The CRO should be able to explain how it evaluates whether a site can reliably execute the entire specimen-to-result pathway, not merely whether the investigator has sufficient patients.

6. Ask how the CRO manages multicountry IVDR studies

European IVD studies become substantially more complicated when multiple Member States are involved. National requirements can vary, including practical expectations around:

competent-authority submissions;
ethics submissions;
documentation and translations;
local representatives;
sample collection and laboratory locations;
country-specific submission processes.

Ask how many European IVD performance studies the CRO has actually submitted and managed across multiple countries. Then go deeper: which Member States, which IVD types, which study pathways, how combined CTR/IVDR documents were controlled, how country-specific requirements were tracked and how modifications were managed.

7. Make change control a selection criterion

Assays change during drug development. That is normal. What matters is whether the development organization can assess the consequences.

Changes may involve:

antibodies;
primers or probes;
algorithms or software;
instruments;
cut-offs;
reagents;
manufacturing processes;
laboratories;
specimen types;
pre-analytical workflows.

The CRO should have a defined mechanism for asking whether a change affects analytical performance, clinical performance, patient management, the intended purpose, study documentation or regulatory authorization.

8. Understand the difference between the clinical trial assay and the final CDx

The assay used during early or pivotal drug development may not be identical to the final commercial companion diagnostic. Sponsors should determine early whether there may be differences in:

platform;
laboratory;
reagents;
software;
manufacturing;
specimen preparation;
cut-off;
intended-use population.

If so, a bridging strategy may eventually be necessary. The CRO should therefore ask not only how to run the current trial, but what diagnostic evidence will be needed at the end of development and whether today’s decisions make that pathway easier or harder.

9. Evaluate the Notified Body and medicines-authority interface

Under IVDR, companion diagnostics undergo conformity assessment involving a Notified Body, with a scientific-opinion process involving a medicines authority. For centrally authorized medicinal products, the Notified Body seeks EMA’s scientific opinion on the suitability of the CDx in relation to the medicinal product before issuing the relevant certificate.

Your CRO should understand how development decisions made during the clinical trial can eventually affect diagnostic technical documentation, Notified Body review, medicines-authority consultation and drug/CDx labeling. A CRO does not replace the manufacturer, Notified Body or medicines authority, but it should understand the pathway well enough to avoid preventable downstream problems.

10. Do not confuse laboratory capability with CRO capability

Laboratories and CROs solve different problems.

Provider model	Usually strongest when…
Laboratory-led provider	Assay development is intensive; centralized testing is critical; technology transfer is difficult; testing complexity is the dominant risk.
Specialist IVD/CDx CRO	Regulatory strategy is complex; multiple countries are involved; IVDR/FDA coordination matters; a performance study runs alongside a drug trial; several labs or diagnostic partners must be integrated.
Large generalist CRO	The drug program dominates operational complexity; global site reach is the main need; specialist IVD expertise is retained elsewhere.
Regulatory consultancy	The primary need is pathway strategy or documentation and the sponsor already has clinical-operations infrastructure.

The important point is not to choose based on organizational category. Choose based on where the program’s greatest execution risk sits.

A practical IVD/CDx CRO scorecard

Sponsors can use the following framework during an RFP. Score each category from 1 to 5 and apply the weighting appropriate to the program.

Selection criterion	Suggested weighting
IVD/CDx regulatory expertise	15%
Drug-diagnostic co-development experience	15%
IVDR/FDA study-pathway experience	12%
Clinical performance study design	10%
Analytical-performance understanding	8%
Multicountry execution	10%
Site/laboratory qualification and monitoring	8%
Sponsor-delegation model and governance	8%
Data/statistics/reporting capability	6%
Change control and lifecycle thinking	5%
Relevant team and senior-expert access	3%

The weighting should change depending on the program. A Phase I biomarker exploratory study and a pivotal Phase III CDx co-development program should not use identical criteria.

12 questions every sponsor should ask a potential IVD/CDx CRO

How would you classify the regulatory status of our assay in each target jurisdiction?
Is our assay actually a CDx, an investigational IVD, a clinical trial assay or something else at this stage?
What evidence should be complete before the assay is used prospectively in patient selection?
Which IVDR or FDA investigational pathway do you believe applies, and why?
Who should hold the performance-study sponsor responsibilities?
How would you divide responsibilities between pharma, the diagnostic manufacturer, laboratory and CRO?
How do you coordinate an IVDR performance study running alongside a medicinal-product clinical trial?
What happens if the assay changes halfway through the trial?
How do you qualify and monitor testing laboratories and sample-collection sites?
What is your approach to device deficiencies and diagnostic-related safety reporting?
How do you ensure today’s clinical trial assay supports the eventual commercial CDx strategy?
Can the senior experts presenting during the bid remain involved after award?

Red flags when selecting an IVD/CDx CRO

“We manage devices just like any other clinical-trial supply.” They are not the same.

“The laboratory handles everything related to the assay.” A laboratory can execute testing without owning the regulatory consequences of how that assay is used.

“The drug IND/CTA covers the diagnostic.” Do not assume that the medicinal-product pathway automatically resolves device obligations.

“We will determine the IVDR pathway after site selection.” The regulatory pathway can determine how and where the study should be conducted.

“ISO 20916 is basically the IVD version of ICH-GCP.” There are parallels, but this oversimplifies IVD-specific responsibilities and operational requirements.

“We have done hundreds of device trials.” Ask how many were actually IVD performance studies or CDx programs.

“Our global footprint means we know every local requirement.” Ask for country-specific examples.

“Bridging can be addressed after the pivotal trial.” Sometimes it can. Sometimes that decision creates significant downstream risk.

The best CRO should challenge your development plan

Sponsors often evaluate CROs on responsiveness. Responsiveness matters. But for a complex precision-medicine program, technical challenge can be more valuable than agreement.

A strong partner should be willing to say:

the assay is not sufficiently mature;
the intended purpose is not yet clear;
the study design will not support the future claim;
a cut-off strategy requires further evidence;
the diagnostic and drug timelines are misaligned;
the proposed laboratory is not suitable;
a regulatory interaction should happen earlier;
the responsibility model creates a gap.

The purpose of specialist expertise is not merely to execute the sponsor’s original plan. It is to identify risks before regulators, investigators or pivotal-study data reveal them.

Where specialist IVD/CDx CROs add the most value

The case for specialist support becomes strongest when several of the following apply simultaneously:

the biomarker determines patient treatment or eligibility;
the assay may become a companion diagnostic;
EU IVDR requirements apply;
the trial spans multiple Member States;
the assay is non-CE-marked or being used outside its intended purpose;
a therapeutic trial and IVD performance study run in parallel;
FDA IDE/CDx considerations exist;
the assay is NGS-, PCR-, IHC- or software-based and technically complex;
multiple laboratories are involved;
the clinical trial assay may differ from the final commercial device;
diagnostic changes are expected during development;
the sponsor needs to delegate significant IVD-study responsibilities.

The value of specialization In these circumstances, the value of specialization is not simply regulatory knowledge. It is integration.

What a good operating model looks like

A well-run precision-medicine program should create one integrated development view across four layers:

Layer	Focus
Therapeutic development	Protocol, endpoints, recruitment, treatment and medicinal-product regulatory strategy.
Diagnostic development	Intended purpose, analytical performance, clinical performance, design controls and commercial CDx strategy.
Clinical operations	Sites, laboratories, samples, monitoring, data, deviations and study documentation.
Regulatory execution	IVDR, CTR, IDE/IND, ethics, competent authorities, FDA, Notified Body and medicines-authority interfaces.

The program fails when these four layers are optimized independently. The best CRO model therefore creates a single governance structure across the interfaces, even when several organizations remain legally responsible for different activities.

How MDx CRO approaches IVD/CDx clinical development

MDx CRO’s precision-medicine model is designed around the intersection between diagnostic regulation and clinical execution. Its CDx services span biomarker and regulatory strategy, analytical-validation planning, IVDR/FDA pathways, study design, sponsor delegation, testing-site management, ISO 20916-aligned monitoring, biostatistics, regulatory submissions and performance reporting.

Its broader IVD clinical-study operation covers study planning, CPSP development, ethics and competent-authority submissions, site and laboratory management, monitoring, data management, regulatory communications and multinational study coordination.

Best fit This operating model is particularly relevant when a sponsor needs to connect pharma clinical development + diagnostic development + IVDR/FDA strategy + multinational clinical execution.

Sponsors should apply the same standard to MDx CRO that they apply to every potential provider: ask for relevant evidence, named experts, responsibility allocation and examples that match the complexity of the specific program.

Final perspective

Choosing an IVD/CDx CRO is not primarily about finding a company that can monitor sites or prepare regulatory documents. It is about controlling the interfaces between a therapeutic product and the diagnostic evidence supporting its precision-medicine strategy.

The strongest partner should be able to answer four questions clearly:

1. What is the diagnostic regulatory strategy? Not generically. For your specific assay, intended purpose and jurisdictions.

2. Is the assay ready for the proposed clinical use? Scientifically, analytically and operationally.

3. Who owns every IVD/CDx responsibility during the trial? There should be no invisible gaps between pharma, diagnostic manufacturer, CRO and laboratory.

4. Will today’s study support tomorrow’s regulatory and commercial objective? The clinical trial assay, pivotal evidence and final CDx strategy need to form one development continuum.

If a CRO cannot connect those four questions, it may still be an excellent service provider. But it is probably not the right IVD/CDx development partner for a complex precision-medicine clinical trial.

Frequently asked questions

What is an IVD/CDx CRO?

An IVD/CDx CRO is a contract research organization with specialist capability in clinical and regulatory development of in vitro diagnostics and companion diagnostics. Depending on the provider, services may include regulatory strategy, analytical and clinical performance planning, study design, submissions, site and laboratory management, monitoring, biostatistics and regulatory reporting.

Is a companion diagnostic the same as a biomarker assay?

No. Biomarker assays can serve many research and clinical-development purposes. A companion diagnostic has a specific regulatory meaning tied to the safe and effective use of a corresponding medicinal product.

Does every CDx performance study require an IVDR application?

No. The pathway depends on factors including device status, intended purpose, study design and sample use. Certain studies using only leftover samples may follow a notification route rather than the standard application route.

Can a drug CRO manage the companion diagnostic workstream?

Potentially, if it has genuine IVD/CDx regulatory and clinical-performance expertise. Sponsors should assess the team’s actual diagnostic experience rather than assuming pharmaceutical clinical-trial experience automatically transfers to IVD development.

When should an IVD/CDx CRO be involved?

Ideally before the pivotal study design is fixed. Early involvement allows the team to assess assay maturity, intended purpose, regulatory pathway, analytical evidence, study design, country strategy and the relationship between the clinical trial assay and final commercial CDx.

What is the most important factor when choosing a CDx CRO?

For complex programs, the most important factor is usually integration capability: whether the CRO can connect diagnostic science, regulatory strategy and clinical execution with the therapeutic-development timeline.