Draft monograph: Thymalin — submissions
The 10 submissions received, published in full with declared interests and secretariat responses.
§2Submissions and responses
10 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.
The document should not describe uses outside the approved indication
Having read the draft monograph on Thymalin, the respondent puts one point to the committee.
The submission is made on behalf of a marketing-authorisation holder. It states that the draft describes uses of the compound that fall outside the approved indication, that such uses are not supported by the sponsor, and that describing them may be read as legitimising them.
The sponsor asks that the sections concerned be removed, or in the alternative that they carry a prominent statement that the sponsor does not support such use.
The secretariat does not accept this submission. The Institute records what is supplied and what is used, because a reader encountering a compound outside a regulated route is the reader most in need of an assessment of the evidence for it.
The sections remain. Every such section already states the regulatory status of the use described and states that the evidence for it is assessed separately from the evidence for the approved indication. The submission is published in full and identified as an industry submission.
Anti-drug antibody data are omitted
The respondent notes that this class is supplied in an injectable presentation, and submits with that in view.
The respondent states that immunogenicity is measured in the development programmes of peptide therapeutics and that the monograph does not report it, leaving a reader unable to judge whether loss of effect over time has an immunological explanation.
The respondent proposes that anti-drug antibody incidence and its relation to effect be reported for every compound in the series.
The secretariat accepts this submission in part. Immunogenicity is reported where a contributing trial reported it. The proposal to report it for every compound is declined because for many compounds in the series no such data exist and a uniformly empty row is not informative.
Anti-drug antibody incidence and any reported association with loss of effect are now reported where measured, and recorded as not measured where the contributing trials did not assess them.
Doses are expressed in units that differ between sections
The respondent has read the draft covering Thymalin and makes one submission.
The draft expresses dose in milligrams in one section and in micrograms per kilogram in another, drawn from different sources without conversion. The respondent states that this is the shape of error that reaches a patient.
The respondent proposes a single unit throughout, with the source unit retained in parentheses where a conversion was performed.
The secretariat accepts this submission. The inconsistency was inherited from the sources and should have been resolved in drafting.
A single dose unit is now used throughout each monograph, with the source unit retained in parentheses wherever a conversion was applied, and every conversion is stated rather than performed silently.
The pharmacokinetic section does not connect half-life to the dosing schedule
The respondent submits on the draft monograph for Thymalin. An immune modulator supplied outside a regulated route needs a document that is explicit about what the material actually is.
The draft reports a half-life and, separately, a dosing interval. The respondent, a clinical pharmacologist, states that the relationship between the two is what determines accumulation and time to steady state, and that the monograph leaves the reader to derive it.
The respondent proposes that time to steady state be stated explicitly, with the assumption from which it was derived.
The respondent’s submission overlaps with submission 002 and was prepared without sight of it.
The secretariat accepts this submission. The derivation is short, it is decision-relevant, and leaving it to the reader invites it to be done wrong.
The pharmacokinetic section now states approximate time to steady state alongside the half-life and dosing interval, with the assumption of first-order elimination stated, and records where the assumption is not supported for this compound.
The preclinical section is extensive and the clinical section is not
The respondent’s comment on the draft for Thymalin arises from the differences in regulatory status between jurisdictions, which for this class are wider than usual.
The draft summarises a large animal literature and a small or absent human literature. The respondent states that the resulting document reads as though a great deal is known, when what is known concerns rodents.
The respondent proposes that the preclinical section be reduced to a statement of what has been observed in animals and that the detail be removed entirely.
The secretariat accepts this submission in part. The section is shortened and given a standing statement. The proposal to remove the detail is declined, because a reader encountering claims derived from that literature needs to be able to see what it actually contains.
The preclinical section is reduced in length, placed after the clinical assessment rather than before it, and opens with a standing statement that an effect observed in an animal model is not a clinical outcome and does not support a certainty rating.
Point estimates are given without an interval
The respondent has read Thymalin and submits on a matter of presentation.
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 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.
Trials are described as terminated where they completed as planned
Having read the draft under consultation, which concerns Thymalin, the respondent submits as follows.
The respondent states that the draft uses the word terminated for trials stopped at pre-specified interim analyses, for trials stopped for futility and for trials closed for commercial reasons, and that these are three different facts.
The respondent proposes that the status vocabulary be fixed and defined in the glossary.
The respondent has read submission 006 and asks that this submission be considered with it.
The secretariat accepts this submission in part. The vocabulary is fixed and defined. The proposal to distinguish commercial closure from futility in every case is accepted only where the Institute holds a document stating the reason.
Trial status now uses a fixed vocabulary defined in the glossary, and where the reason for stopping is not evidenced by a document the Institute holds, the status is recorded as stopped with the reason not established rather than assigned.
The document is unreadable without specialist training
The respondent submits on Thymalin.
The respondent states that the draft is written for a reader who already understands certainty grading, and that the people most affected by the subject matter will not reach the assessment at all.
The respondent proposes a plain-language summary at the head of every document, written to the same standard of accuracy as the document itself and not as a promotional abstract.
The secretariat accepts this submission in part. A plain-language summary is added. The proposal that it replace the technical abstract is declined, because the abstract is the part of the document other assessors read and cite.
Every document now opens with a plain-language summary of not more than 150 words, placed above the technical abstract and carrying the same certainty language, so that the two cannot diverge.
The route of administration studied is not the route in which the compound is supplied
The respondent read the draft on Thymalin and has confined this submission to one matter.
The clinical section describes findings obtained by one route and the supply section describes presentations intended for another. A reader moving between the two sections will carry the effect estimate across the change without noticing that it has been carried, because nothing on the page marks the transition.
The respondent proposes that where the studied route and the supplied presentation differ, the difference be stated in the assessed-outcome table itself rather than in the supply section, on the ground that a reader consults the outcome table and does not always reach §8.
The secretariat accepts this submission. The route by which an estimate was generated is a condition of the estimate and belongs beside it.
The assessed-outcome table now carries the studied route in every row, and a standing note appears wherever the supplied presentation differs from it.
Mechanistic claims for a peptide fragment are carried without evidence that the fragment acts as described
This submission concerns the draft on Thymalin. The respondent’s interest is in preparations whose composition is not fully defined.
The respondent states that the draft repeats a mechanistic account originating in supply documentation rather than in the primary literature, and that the account attributes activity to a fragment on the basis of the activity of the parent molecule.
The respondent proposes that any mechanistic claim be traceable to a primary source and removed where it is not.
The secretariat accepts this submission. A mechanism repeated from marketing material has no evidential status regardless of how widely it is repeated.
Mechanistic claims not traceable to a primary source are removed, and those retained carry their source and a statement of whether the underlying work was conducted in vitro, in animals or in humans.
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.
- 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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