Independent · non-commercial · publishes on a quarterly cycle|Current cycle 2026 Q3
Compound Evidence InstituteEvidence synthesis · established 2023Graded assessments of compounds, trials, methods and supply
Document set current to 30 July 2026
Public comment period · §2

Draft standard CEI-MS-11: Determination of aggregate content… — submissions

The 12 submissions received, published in full with declared interests and secretariat responses.

Document identifier
CEI-CP-091/2
Series
Public comment period
Version
1.0
Published
26 Feb 2026
Last reviewed
26 Feb 2026
Next review
26 Feb 2027
Identifier
10.71829/cei.cp.91
Certainty
Not rated
Cycle
2026 Q1
Window
13 Jan 2026 – 12 Feb 2026
Status
Closed
Submissions
12

§2Submissions and responses

12 submissions were received. Each is published in full below with its declared interest, the secretariat response and the disposition. The Institute publishes submissions it did not accept in the same form as those it did.

Professor Bartolomeu Nkosi-Lindegaard, PhD Professor of Regulatory Science · submitting on regulatory science
DRAFT-AGGREGATES-S/001 received 15 Jan 2026

The standard does not require retention of the primary data

The respondent submits on CEI-MS-11, Determination of aggregate content by size-exclusion chromatography, on a matter that is not specific to this draft but is visible in it.

The respondent states that a reported figure cannot be checked without the chromatogram or spectrum from which it was derived, and that the draft requires only the figure.

The respondent proposes a retention requirement with a stated period.

Declared interest. No financial or non-financial interest to declare in relation to the subject of this consultation.
Secretariat responseNoted, no amendment26 Feb 2026

The secretariat notes this submission. Retention is addressed in the certificate-of-analysis minimum data standard, which requires that primary data be retained and be identifiable from the certificate, and which applies to every determination reported on a certificate.

No amendment arises. The requirement exists in the standard that governs reporting rather than in each determination standard, and the cross-reference has been added here so that a reader working from this document alone can find it.

Ivo Mountstephen, MSc (Clinical Pharmacy) National medicines information service · submitting on medicines information
DRAFT-AGGREGATES-S/002 received 16 Jan 2026

A determination does not record the version of the standard it was made under

This submission addresses the draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography from the standpoint of a reader who will act on a result produced under it.

The respondent states that the standard will be revised and that results reported under different versions will circulate together, indistinguishable from one another.

The respondent proposes that the standard identifier and version be carried on the face of every determination.

The respondent has read submission 001 with interest and adds one observation the secretariat may find useful.

Declared interest. Holds a personal shareholding, below the Institute's materiality threshold, in a diversified fund with pharmaceutical sector exposure. No direct holding in any named company.
Secretariat responseAccepted03 Mar 2026

The secretariat accepts this submission. A conformance claim against an unspecified version is not a conformance claim.

Every determination reported under this standard now carries the standard identifier and version on its face, and a claim of conformance that does not identify the version is recorded by the Institute as not conformant.

Dr Lorcan Uttridge, PhD (Clinical Biochemistry) ISO/IEC 17025-accredited contract testing laboratory · submitting on clinical biochemistry
DRAFT-AGGREGATES-S/003 received 20 Jan 2026

The matrix interferes with the determination and no control is required

Having read the draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography, the respondent puts one point to the secretariat.

The respondent states that the matrices in scope can suppress or enhance the response, and that without an inhibition and enhancement control a result cannot be attributed to the analyte.

Data showing recovery outside acceptable limits in an uncontrolled matrix accompanied the submission.

Declared interest. Employed by an analytical laboratory that performs contract testing for suppliers, including at least one supplier named in the Institute's assessment set.
Secretariat responseAccepted18 Mar 2026

The secretariat accepts this submission. A determination on an interfering matrix without a validated control establishes nothing, and the draft permitted one.

An inhibition and enhancement control is now required for every determination under this standard, with stated recovery limits, and a determination reported without it is recorded as not conformant rather than as a low result.

Dr Yehudit Yorkstone, PhD (Chemistry), MRSC Academic peptide-chemistry group · submitting on peptide chemistry
DRAFT-AGGREGATES-S/004 received 22 Jan 2026

The standard assumes a reference standard of known assigned content

The draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography was read from the standpoint of a laboratory reconstituting material for analysis.

The respondent states that for many compounds in scope no reference standard with an assigned content exists, and that the standard as drafted has nothing to say to a laboratory in that position.

The respondent proposes that the standard state what can be determined without one and how such a determination should be labelled.

Declared interest. No financial or non-financial interest to declare in relation to the subject of this consultation.
Secretariat responseAccepted01 Mar 2026

The secretariat accepts this submission. A standard applicable only where a reference standard exists is silent in the cases most in need of it.

The standard now states which determinations remain available without a reference standard of assigned content, requires that such determinations be labelled as relative rather than absolute, and requires the assumption used in place of an assigned content to be stated.

Dr Kolawole Isaksen-Balogun, PhD (Biostatistics) Independent evidence-synthesis consultancy · submitting on biostatistics
DRAFT-AGGREGATES-S/005 received 28 Jan 2026

Point estimates are given without an interval

The respondent submits on the draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography. A physical-quality attribute is informative and routinely left unreported, and a standard that makes one routine is worth having.

Several estimates in the draft appear as single figures. The respondent states that a point estimate without an interval invites a precision the underlying data do not support, and that the effect is worst where the estimate is drawn from a small contributing set.

The respondent proposes that no point estimate appear anywhere in the document set without its interval, including in summary tables and in the abstract.

The respondent notes that submission 004 has already been made and confines this submission to a matter not covered by it.

Declared interest. Has previously served as an investigator on a trial included in the evidence base under consultation. Received no personal payment; institutional payment was made to the trial site.
Secretariat responseAccepted in part27 Feb 2026

The secretariat accepts this submission in part. Intervals are added wherever the source reports one. The proposal is declined for figures the source published without an interval, because the Institute will not compute an interval a source did not report.

Every estimate now carries its interval where the source reported one, and where it did not, the estimate is annotated as reported without an interval rather than left to appear as a precise figure.

Bertrand Ollerenshaw, MSc (Regulatory Affairs) Regulatory affairs, marketing-authorisation holder · submitting on regulatory science · industry submission
DRAFT-AGGREGATES-S/006 received 02 Feb 2026

The additional determinations required would materially increase release testing cost

The respondent notes that CEI-MS-11, Determination of aggregate content by size-exclusion chromatography will be applied to lyophilised material whose appearance changes on storage, and submits with that in view.

The submission is made on behalf of a manufacturer. It states that the draft adds two determinations to those in existing compendial practice, and estimates the additional analytical burden per batch.

The submission does not dispute the analytical reasoning and asks that one of the two be made conditional rather than universal.

Declared interest. Is an employee of a marketing-authorisation holder for a compound named in the draft. This submission is made on behalf of that company and is identified as an industry submission throughout.
Secretariat responseAccepted in part01 Mar 2026

The secretariat accepts this submission in part. One determination is made conditional on a stated risk factor. The other is retained because the evidence supplied by the respondent does not bear on whether it is necessary, only on what it costs.

One of the two determinations is now required only where the stated risk factor is present, with the factor defined in the scope, and the other is retained as a universal requirement with the reasoning stated. The submission is identified as an industry submission.

Dr Abimbola Sotomayor-Ekwueme, PharmD, PhD Reader in Pharmaceutics · submitting on pharmaceutics
DRAFT-AGGREGATES-S/007 received 05 Feb 2026

The standard does not state that a determination on one unit says nothing about the batch

The respondent has read CEI-MS-11, Determination of aggregate content by size-exclusion chromatography in draft and makes one submission.

The respondent states that determinations under this standard are generally performed on a single unit and that certificates then travel with every unit of a batch, so that a single-unit result is routinely read as a batch result.

The respondent proposes that the standard require a sampling statement on the face of every determination.

Declared interest. Has received consultancy fees from a supplier named in the Institute's supplier assessment set within the preceding two years.
Secretariat responseAccepted23 Feb 2026

The secretariat accepts this submission. The inference from unit to batch is the most consequential unstated assumption in supply documentation.

Every determination made under this standard now carries a sampling statement recording how many units were sampled, from what population and by what plan, and the standard states that a determination on a single unit supports no inference about any other unit.

Dr Quentin Zimmerthal, PhD (Chemistry), CChem Independent analytical consultancy · submitting on analytical chemistry
DRAFT-AGGREGATES-S/008 received 08 Feb 2026

Nothing in the standard addresses transfer of the method between laboratories

This is a submission on the draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography, made by a respondent who applies comparable procedures daily.

The respondent states that determinations under this standard will be performed by different laboratories on the same material and that without transfer criteria their results are not comparable.

The respondent proposes a transfer protocol with acceptance criteria for inter-laboratory agreement.

Declared interest. Has received consultancy fees from a supplier named in the Institute's supplier assessment set within the preceding two years.
Secretariat responseAccepted in part24 Feb 2026

The secretariat accepts this submission in part. Acceptance criteria for agreement between laboratories are added. A full transfer protocol is not, because transfer is a quality-system activity rather than a determination and the series does not address quality systems.

The standard now states the maximum difference between laboratories analysing the same sample at which results are treated as agreeing, and requires that a comparison across laboratories state whether that criterion was met.

Dr Oisín Rautavaara, PhD (Pharmacoepidemiology) Public-sector clinical trials unit · submitting on biostatistics
DRAFT-AGGREGATES-S/009 received 08 Feb 2026

Rounding conventions are not stated and change the reported result

The respondent has read CEI-MS-11, Determination of aggregate content by size-exclusion chromatography and submits on a matter of presentation.

The respondent states that the draft reports figures to varying precision and does not specify when rounding occurs in the calculation chain, which can move a result across an acceptance limit.

The respondent proposes that rounding occur only at the reporting step and that the convention be stated.

Declared interest. Has previously served as an investigator on a trial included in the evidence base under consultation. Received no personal payment; institutional payment was made to the trial site.
Secretariat responseAccepted02 Mar 2026

The secretariat accepts this submission. Intermediate rounding is a silent source of disagreement between laboratories analysing the same material.

The standard now requires that no rounding be applied before the reporting step, states the reporting precision for each quantity, and states the rounding convention used at that step.

Dr Liesbeth Achterberg, PhD (Clinical Biochemistry) ISO/IEC 17025-accredited contract testing laboratory · submitting on clinical biochemistry
DRAFT-AGGREGATES-S/010 received 10 Feb 2026

Nothing requires a laboratory to demonstrate ongoing performance

This submission concerns CEI-MS-11, Determination of aggregate content by size-exclusion chromatography and a convention used across the Institute’s output.

The respondent states that suitability criteria assessed within a run demonstrate that the run worked and not that the laboratory performs consistently over time.

The respondent proposes participation in a proficiency scheme as a condition of conformance.

Declared interest. Holds a personal shareholding, below the Institute's materiality threshold, in a diversified fund with pharmaceutical sector exposure. No direct holding in any named company.
Secretariat responseAccepted in part10 Mar 2026

The secretariat accepts this submission in part. A trend requirement on system suitability data is added. Proficiency scheme participation is not made a condition of conformance, for the same reason competence requirements are not.

The standard now requires that system suitability results be trended across runs and that a determination report whether the trend was within the laboratory's stated limits, which places the demonstration inside the document the Institute can read.

Dr Ivo Quintanilha, MD, MSc (Clinical Trials) University department of public health · submitting on evidence synthesis
DRAFT-AGGREGATES-S/011 received 11 Feb 2026

Absence of evidence is presented in a form a reader will take as negative evidence

The respondent read the draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography and has confined this submission to a single requirement.

Where the Institute has identified no study, the draft states that no evidence was found. In several places that sentence sits immediately after a paragraph describing an adverse outcome, and the juxtaposition invites the reading that the compound was studied and found wanting.

The respondent proposes a standing formulation, used identically wherever the situation arises, distinguishing an outcome that was studied and not demonstrated from an outcome that has not been studied at all.

The respondent endorses the general approach taken in submission 001 and asks that it be extended to the matter identified here.

Declared interest. No financial interest. Has published a systematic review reaching a different conclusion from the draft, which the respondent declares as a non-financial interest.
Secretariat responseAccepted23 Feb 2026

The secretariat accepts this submission. The two states are different, they support different decisions, and the draft rendered them in language a reader could not reliably separate.

A standing formulation has been adopted and is applied wherever an evidence gap is recorded, distinguishing an outcome assessed and not demonstrated from an outcome not assessed. The formulation is identical at every occurrence so that it can be recognised at a glance.

Dr Xenia Nyquist-Obiora, PhD (Pharmaceutics) Regional hospital pharmacy department · submitting on pharmaceutics
DRAFT-AGGREGATES-S/012 received 12 Feb 2026

Nothing addresses the container the material was held in

The respondent’s comment on the draft of CEI-MS-11, Determination of aggregate content by size-exclusion chromatography arises from performing examinations of this kind in a pharmacy setting.

Adsorption to the container and oxidation in the headspace both change what is measured, and both depend on the container rather than on the material. The standard treats the vial as neutral.

The respondent proposes that container type and headspace atmosphere be reported where they are known.

Declared interest. Holds a patent relating to a delivery technology referenced in the draft.
Secretariat responseAccepted in part13 Mar 2026

The secretariat accepts the reporting requirement where the information is held and declines to require it where it is not.

Container type and headspace atmosphere are now reported where known, and recorded as not held where they are not, rather than omitted.

References cited on this page

References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.

  1. International Organization for Standardization. ISO/IEC 17025:2017 General Requirements for the Competence of Testing and Calibration Laboratories. ISO/IEC Standard 2017;3rd edition. identifier not held by the Institute

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