Protocol Feasibility Assessment as an ICH E8 Quality-by-Design Gate: Run It on the Draft, Before Lock

At a glance

• Protocol feasibility is not the same as country or site feasibility. It pressure-tests a draft protocol against real-world population, site, and operational constraints, and its job under ICH E8(R1) is to surface critical-to-quality (CtQ) factors, not to predict recruitment for a business-development pipeline.
• ICH E8(R1) §3.3.5 frames a feasibility assessment as a quality-by-design activity: a successful study rests on a protocol that is both scientifically sound and operationally feasible, and design choices that fail that test should change the design.
• Run the gate on the draft. ICH E6(R3) §3.10.1.1 expects the sponsor to identify risks to CtQ factors prior to trial initiation, which means before lock, while the protocol can still be redesigned rather than deviated around.
• The deliverable is a CtQ-mapped feasibility form covering eligibility realism, assessment burden, visit schedule, site and equipment capability, comparator and standard-of-care availability, and data-capture load.
• Some findings force a protocol redesign (the design element is unworkable); others are acceptable operational mitigations. The triage rule is whether the finding hits a critical-to-quality factor or merely a logistics detail.
• Magpie and any feasibility tooling can structure and document this gate, but the sponsor remains responsible for quality management and protocol design under ICH E6(R3) §3.10. Tooling enables the obligation; it does not discharge it.

The most common feasibility anti-pattern in clinical operations is mailing a questionnaire to candidate sites after the protocol is already final and calling the response rate “feasibility.” That exercise answers a recruitment question for a business-development pipeline. It does not answer the question ICH E8 actually poses, which is whether the protocol you are about to lock will run at all without generating a wave of deviations and amendments. This article reframes protocol feasibility as a quality-by-design gate you run on the draft, and it gives you the three-feasibility decision table, the CtQ-mapped form, and the redesign-versus-mitigate triage rule a clin-ops lead needs to run the gate this week.

The three feasibilities teams confuse, and why only one is “protocol” feasibility

Practitioners use “feasibility” for three distinct activities, and conflating them is how protocols pass a feasibility check and still fail in the clinic.

Level	Core question	Typical owner	Timing
Program / portfolio	Should we run this development program at all, given indication and competitive landscape?	Sponsor strategy, medical	Pre-protocol concept
Country / site selection	Which countries and sites can recruit and run this finished protocol?	Clin-ops start-up, business development	After or near protocol lock
Protocol feasibility	Will this draft design actually run against real population, site, and operational constraints?	Sponsor clin-ops and protocol authors	On the draft, before lock

Only the third is protocol feasibility. Country and site feasibility take the protocol as a fixed input and rank places to run it. Protocol feasibility takes the design itself as the variable under test. ICH E8(R1) §3.3.5 makes the operational dimension part of the protocol’s quality: it states that the foundation of a successful study is a protocol that is both scientifically sound and operationally feasible, and that a feasibility assessment involves consideration of study design and implementation elements that could impact successful completion from an operational perspective. That is a statement about the design, not about a vendor’s site list. Site selection scoring and country-feasibility ranking are real activities, but they are a different gate with a different owner, and naming them here is only to draw the boundary.

Why protocol feasibility is an ICH E8 quality-by-design gate, not a recruitment survey

Quality by design is the organizing idea of ICH E8(R1): §3.1 sets out that quality should be driven proactively by designing quality into the study protocol and processes, rather than inspected in afterward. ICH E8(R1) §3.2 assigns the sponsor and other parties designing quality into a clinical study the responsibility to identify the critical-to-quality factors, the attributes whose integrity is fundamental to participant protection and to the reliability and interpretability of results. Protocol feasibility is where you stress-test whether the draft’s design elements actually support those factors.

ICH E6(R3) carries the same obligation into the GCP requirements that bind the sponsor. ICH E6(R3) §3.10 requires the sponsor to implement an appropriate system to manage quality throughout all stages of the trial, and it defines quality management to include the design and implementation of efficient clinical trial protocols, incorporating quality into the design (quality by design) and identifying critical-to-quality factors as described in ICH E8(R1). ICH E6(R3) §3.1.2 makes it explicit that sponsors should incorporate quality into the design of the clinical trial by identifying factors critical to quality and by managing risks to those factors. A feasibility check whose only output is a predicted enrolment number does none of this. It does not identify CtQ factors, and it does not feed design.

The two regulations align cleanly here, which is worth saying plainly: ICH E8(R1) supplies the quality-by-design framework and the CtQ-factor vocabulary, and ICH E6(R3) §3.10 binds the sponsor to operate it. There is no tension to reconcile between them on this point; E6(R3) explicitly points back to E8(R1) for the definition of critical-to-quality factors.

Run it on the draft, not the final: where the gate sits in the protocol lifecycle

If feasibility runs after lock, its findings can only become deviations and amendments, because the design is frozen. The regulations put the gate earlier. ICH E6(R3) §3.10.1.1 requires the sponsor to identify risks that may have a meaningful impact on critical-to-quality factors prior to trial initiation, across processes including trial design and participant selection. “Prior to trial initiation” and “trial design” together mean the assessment belongs on the draft, while the design is still movable.

ICH E8(R1) §3.3.3 reinforces who you need in the room at draft stage: it states that clinical investigators and potential study participants have valuable insights into the feasibility of enrolling participants who meet proposed eligibility criteria, whether scheduled study visits and procedures may be overly burdensome and lead to early dropouts, and the general relevance of endpoints to the targeted population. Those insights are only actionable before lock. ICH E8(R1) §3.3 also instructs that study designs should be operationally feasible and avoid unnecessary complexity, which is a design instruction, not a site-selection one. The practical reading: convene investigators and, where appropriate, patients against the draft, and treat their feasibility input as design input.

What to actually test: turning design elements into critical-to-quality factors

The gate works by taking each protocol design element and asking what critical-to-quality factor it touches and whether the draft, as written, keeps that factor intact. ICH E8(R1) §3.3.5 names the operational considerations a feasibility assessment should cover: regional differences in medical practice and patient populations, the availability of qualified investigators and site personnel with experience conducting the study (citing ICH E6), availability of equipment and facilities required to conduct the study, availability of the targeted patient population, and the ability to enrol a sufficient number of participants to meet the objectives. Retention and follow-up are also named as key critical-to-quality factors.

ICH E6(R3) §3.7.1 adds the site-capability half of the test from the GCP side: the sponsor is responsible for selecting investigators, each of whom should be qualified by education, training, and experience and should demonstrate adequate resources and facilities to properly conduct the trial. If the draft assumes an assessment that candidate sites cannot resource or staff, that is a feasibility finding, not a start-up detail.

The feasibility assessment form, section by section

This is the deliverable readers came for: a feasibility form whose sections map to CtQ factors rather than to a recruitment funnel. Each row pairs a protocol design element with the factor it endangers and the question you put to investigators against the draft.

Form section (design element)	CtQ factor at risk	Question against the draft
Eligibility realism	Adequate, representative enrolment	Do real candidates at the bedside meet every inclusion/exclusion criterion as written, or do the criteria exclude the population you need?
Assessment and procedure burden	Participant retention and follow-up	Are the procedures so burdensome they will drive early dropout, per the dropout risk ICH E8(R1) §3.3.3 flags?
Visit schedule	Retention; operational feasibility	Can sites and participants sustain the visit frequency and windows, or will the schedule force protocol deviations?
Site and equipment capability	Reliable data; investigator suitability	Do candidate sites have the equipment, facilities, and qualified staff the protocol assumes, per ICH E6(R3) §3.7.1?
Comparator / standard-of-care availability	Scientific validity; operational feasibility	Is the comparator or required standard of care actually available at sites, including across regional differences in medical practice that ICH E8(R1) §3.3.5 names?
Data-capture load	Reliable, fit-for-purpose data	Is the data collection necessary and capturable at site, or does it add complexity ICH E8(R1) §3.3 says to avoid?

The form is a CtQ-identification instrument, which is exactly what ICH E8(R1) §3.2 asks the sponsor to produce. The brief’s “feasibility form” deliverable is this skeleton, not a downloadable template roundup; build it to your therapeutic area and keep it mapped to factors.

Reading the answers: which findings force a redesign vs. an operational mitigation

Not every feasibility finding should change the protocol, and treating every logistics gripe as a redesign trigger paralyzes start-up. Here is the triage rule.

Redesign the protocol when the finding shows that a design element itself is unworkable against a critical-to-quality factor: eligibility criteria that exclude the available population, a visit schedule or procedure burden that will predictably break retention, a comparator that is not available at the sites you need, or an endpoint assessment no realistic site can perform. These are design defects, and ICH E8(R1) §3.3 is explicit that designs should be operationally feasible and avoid unnecessary complexity, which is an instruction to fix the design, not to work around it. ICH E6(R3) §3.1.4 likewise requires the sponsor to ensure that all aspects of the trial are operationally feasible and to avoid unnecessary complexity, procedures, and data collection, which again points back at the design.

Accept an operational mitigation when the design is sound and the gap is in execution: a staffing or training gap a site can close, a logistics arrangement, or a monitoring or risk-control measure. ICH E6(R3) §3.10.1.3 supports this path, providing that risk mitigation activities may be incorporated in protocol design and implementation, monitoring plans, agreements, and training. The dividing line is the CtQ factor: if the finding threatens a factor critical to participant protection or result reliability and the design causes it, redesign; if the design holds and the fix is operational, mitigate and document.

Where teams get it wrong

Four failure modes recur. First, ownership: teams let business development own feasibility as a recruitment-prediction questionnaire, when ICH E6(R3) §3.1.2 places the duty to identify CtQ factors and manage risks to them on the sponsor as a quality-by-design obligation. Second, timing: they run it after lock, so findings can only become amendments. ICH E6(R3) §3.10.1.1 wants risk identification prior to trial initiation. Third, scope: they run country and site feasibility and skip protocol feasibility entirely, so the design is never stress-tested against reality. Fourth, the redesign duty: even when a finding clearly shows a design choice is unworkable, teams ship the protocol anyway and absorb the consequences as deviations. ICH E8(R1) §6.1.1 closes that loop: applying quality-by-design principles may minimise the need for protocol modifications, and if a modification becomes necessary the rationale should be documented in a protocol amendment with the impact on conduct carefully considered. An infeasible design that ships unchanged is buying that amendment, plus the deviations that precede it, at the worst possible time.

The downstream tell: infeasible protocols become deviations and amendments

You can read protocol feasibility failures in the trial’s later record. Over-burdensome visit schedules show up as missed-visit and out-of-window deviations and as dropout. Unrealistic inclusion/exclusion criteria show up as screen-failure rates that starve enrolment, or as eligibility deviations when sites stretch the criteria to enrol. A comparator or standard of care that was never available at sites shows up as treatment deviations or as amendments to change the comparator. ICH E8(R1) §6.1.1 names the mechanism directly: quality-by-design up front minimises the need for protocol modifications, and the modifications that do prove necessary become amendments. The feasibility gate is your chance to catch these before they are written into the protocol rather than after they are written into the deviation log. Sibling topics worth working alongside this gate include protocol deviation classification, critical-to-quality factors and RBQM, and protocol amendment management, each of which is where an upstream feasibility miss eventually surfaces.

A closing caution on language: nothing here certifies that running this gate makes a protocol compliant. ICH E6(R3) §3.10 keeps quality management, and therefore protocol design, the sponsor’s responsibility. A feasibility gate, and any tooling that structures it, enables the sponsor to meet the quality-by-design obligations in ICH E8(R1) and ICH E6(R3). It does not transfer them.

Sources

• ICH E8(R1) General Considerations for Clinical Studies, version r1 (ICH, adopted 6 October 2021) — https://www.ich.org/page/efficacy-guidelines
• ICH E6(R3) Good Clinical Practice, version r3 (ICH, adopted 6 January 2025) — https://www.ich.org/page/efficacy-guidelines