arxiv: 2604.07811 · v1 · submitted 2026-04-09 · 🧮 math.DS · q-bio.OT

Recognition: 2 theorem links

· Lean Theorem

Best Practices on QSP Model Reporting for Regulatory Use: perspectives from ISoP QSP SIG Working Group

Susana Zaph , Blerta Shtylla , Steve Chang , Yougan Cheng , Jingqi Q.X. Gong , Abhishek Gulati , Emma Hansson , Alexander Kulesza

show 7 more authors

Alexander V. Ratushny Federico Reali Conner Sandefur Brian Schmidt Fulya Akpinar Singh Monica Susilo Weirong Wang

Authors on Pith no claims yet

Pith reviewed 2026-05-10 18:17 UTC · model grok-4.3

classification 🧮 math.DS q-bio.OT

keywords QSPregulatory reportingmodel informed drug developmenttiered frameworkbest practicescredibility assessmenttransparencyregulatory review

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The pith

A flexible tiered reporting framework for QSP models facilitates regulatory review while preserving modeling diversity.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper proposes best practices for documenting QSP models when they are used to support regulatory decisions in drug development. It identifies the lack of current guidance as a barrier given the wide variety of QSP applications. The authors recommend a tiered system that adjusts the level of detail based on the model's stage and influence rather than enforcing one fixed template. This approach aims to increase transparency and ease review without stifling the flexibility that makes QSP valuable.

Core claim

The paper claims that a tiered reporting framework, informed by real-world regulatory experience and aligned with PBPK and ICH M15 principles, provides the best way to document QSP models for regulatory use by scaling requirements to development phase and model impact.

What carries the argument

The tiered reporting framework that adjusts documentation depth according to development phase and model impact.

If this is right

Regulatory reviews of QSP models become more efficient due to standardized yet flexible documentation.
Transparency in QSP analyses increases across different therapeutic areas and contexts of use.
QSP modeling integrates more readily into model-informed drug development without reporting barriers.
The framework supports a broad range of contexts of use for QSP models while accommodating their diversity.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

Adoption of this framework might encourage more consistent use of QSP in early drug development decisions.
Future iterations could incorporate feedback from actual regulatory submissions using the tiers.
Similar tiered approaches might apply to other quantitative modeling techniques beyond QSP.

Load-bearing premise

That collective real-world regulatory experience is sufficient to define a practical tiered framework that will be broadly applicable and adopted without further empirical testing.

What would settle it

A survey or set of regulatory submissions showing that reviewers require a single uniform template instead of the proposed tiers would show the framework does not meet needs.

read the original abstract

Quantitative systems pharmacology (QSP) models are increasingly applied to inform decision making across drug development and to support regulatory interactions within model informed drug development (MIDD). QSP supports a broad range of applications across drug development and can be tailored to specific therapeutic areas, mechanisms of action, and contexts of use (CoU). While this diversity is a core strength of QSP, it also presents challenges for reporting for regulatory use. Despite the growing impact of QSP models, there is currently no established guidance on how QSP analyses should be documented and reported for regulatory purposes. This white paper, developed by the International Society of Pharmacometrics (ISoP) QSP Special Interest Group Working Group on Credibility Assessment of QSP for Regulatory Use, seeks to address this gap by proposing best practices for QSP model reporting in regulatory settings. The recommendations are grounded in collective real world experience from regulatory interactions and are aligned with reporting guidance established for physiologically based pharmacokinetic (PBPK) modeling and reporting principles outlined in ICH M15. Rather than prescribing a rigid, one size fits all template, this work proposes a flexible, tiered reporting framework that accounts for development phase and model impact. The proposed framework is intended to facilitate regulatory review and enhance transparency while accommodating the inherent diversity of QSP modeling.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

This white paper proposes a flexible tiered reporting framework for QSP models in regulatory settings but offers no worked examples or validation data to show it works in practice.

read the letter

The core takeaway here is a set of recommendations from the ISoP QSP group for how to document models when they go to regulators. They want a tiered approach that changes with the model's stage and its potential impact on decisions, rather than a single rigid template. That matches the diversity of QSP work and builds directly on existing PBPK reporting rules plus ICH M15 principles. The paper is clear that this comes from the group's collective regulatory experience instead of new experiments or derivations. That is the main new element: a structured but adaptable outline where none existed before for QSP specifically. It does a decent job naming the problem and keeping the advice practical instead of overly prescriptive. The soft spots are straightforward. The proposal rests entirely on stated experience without showing even one sample report or testing how the tiers would actually be applied to real submissions. That leaves open whether the framework will be easy to use or will create new interpretation fights. No data on uptake or consistency across groups is given either. Readers who work on QSP submissions or regulatory review will find the most direct value as a discussion starter. It is not a research result with testable claims, so it is not something most people would cite in technical papers. Still, the gap it targets is real and the approach is coherent on its own terms, so it deserves a serious referee round to collect broader feedback before any wider adoption. I would send it out for review rather than desk reject.

Referee Report

1 major / 2 minor

Summary. This white paper from the ISoP QSP Special Interest Group Working Group proposes best practices for reporting Quantitative Systems Pharmacology (QSP) models for regulatory use. It advocates a flexible, tiered reporting framework that scales with development phase and model impact (context of use), grounded in collective real-world regulatory experience and aligned with PBPK guidance and ICH M15 principles, to improve transparency and facilitate review while preserving QSP's application diversity.

Significance. If implemented, the tiered framework could meaningfully reduce ambiguity in QSP submissions under MIDD, providing regulators with clearer documentation expectations without imposing rigid templates that would be ill-suited to QSP's mechanistic and therapeutic heterogeneity. The explicit grounding in collective regulatory experience is a practical strength, offering forward-looking recommendations rather than purely theoretical constructs.

major comments (1)

[§4] §4 (Proposed tiered framework): The framework is described at a conceptual level only, with no concrete reporting templates, sample report outlines, or anonymized case studies drawn from the cited regulatory interactions. This absence is load-bearing because the central claim is that the tiered approach will be practical and broadly adoptable; without illustrative examples, it is impossible to assess whether the tiers actually accommodate QSP diversity or provide reviewers with actionable structure.

minor comments (2)

[Introduction] The abstract and introduction reference alignment with ICH M15 and PBPK guidance but do not include a short mapping table showing how the proposed tiers correspond to specific ICH M15 reporting elements; adding this would improve clarity without altering the argument.
Minor typographical inconsistency in the use of 'CoU' versus 'context of use' across sections; standardize for readability.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the constructive feedback and the recommendation for minor revision. We address the single major comment below.

read point-by-point responses

Referee: §4 (Proposed tiered framework): The framework is described at a conceptual level only, with no concrete reporting templates, sample report outlines, or anonymized case studies drawn from the cited regulatory interactions. This absence is load-bearing because the central claim is that the tiered approach will be practical and broadly adoptable; without illustrative examples, it is impossible to assess whether the tiers actually accommodate QSP diversity or provide reviewers with actionable structure.

Authors: We agree that the current description remains largely conceptual and that concrete illustrations would strengthen the claim of practicality. In the revised manuscript we will add, in §4 and a new appendix, sample report outlines for each of the three tiers. These outlines will be derived from the collective regulatory experience cited in the paper (anonymized and generalized to preserve confidentiality) and will explicitly show how the same core elements scale in detail and emphasis according to context of use. We will retain the explicit statement that these outlines are illustrative rather than prescriptive, thereby preserving the framework’s flexibility while giving reviewers actionable structure. This addition directly addresses the load-bearing concern without converting the white paper into a rigid template. revision: yes

Circularity Check

0 steps flagged

No significant circularity; proposal is a non-derivational guideline

full rationale

The document is a white paper proposing a tiered reporting framework for QSP models, grounded in collective regulatory experience and aligned with external PBPK guidance and ICH M15 principles. It contains no derivation chain, equations, predictions, fitted parameters, or first-principles results that could reduce to inputs by construction. None of the enumerated circularity patterns (self-definitional, fitted-input-as-prediction, self-citation load-bearing, uniqueness imported, ansatz smuggled, or renaming) apply, as the central claim is a forward-looking recommendation rather than an internally derived result. The framework is presented as flexible and experience-based without self-referential definitions or statistical forcing.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The paper rests on domain assumptions about the current state of QSP adoption and the absence of guidance; no free parameters, mathematical derivations, or new postulated entities are introduced.

axioms (2)

domain assumption QSP models are increasingly applied to inform decision making across drug development and to support regulatory interactions within model informed drug development (MIDD).
Stated as background fact in the abstract opening.
domain assumption There is currently no established guidance on how QSP analyses should be documented and reported for regulatory purposes.
Central premise used to justify the need for the proposed framework.

pith-pipeline@v0.9.0 · 5605 in / 1294 out tokens · 45625 ms · 2026-05-10T18:17:47.001842+00:00 · methodology

discussion (0)

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

IndisputableMonolith/Foundation/RealityFromDistinction.lean reality_from_one_distinction unclear

?

unclear
Relation between the paper passage and the cited Recognition theorem.

proposes a flexible, tiered reporting framework that accounts for development phase and model impact
IndisputableMonolith/Cost/FunctionalEquation.lean washburn_uniqueness_aczel unclear

?

unclear
Relation between the paper passage and the cited Recognition theorem.

aligned with reporting guidance established for physiologically based pharmacokinetic (PBPK) modeling and reporting principles outlined in ICH M15

What do these tags mean?

matches: The paper's claim is directly supported by a theorem in the formal canon.
supports: The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends: The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses: The paper appears to rely on the theorem as machinery.
contradicts: The paper's claim conflicts with a theorem or certificate in the canon.
unclear: Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

14 extracted references

[1]

consequence of wrong decision, 5) model risk, and 6) model impact. In addition to the key assessment elements, additional considerations for interaction with regulators are specified to support planning and regulatory interactions: technical criteria, appropriateness of proposed MIDD, evaluation of the model(s) and outcomes, and the outcome of MIDD eviden...
[2]

Assessment of MIDD Evidence

The landscape FDA review s (2) (3) have been helpful to the QSP community since they illustrate the increasing number of FDA submissions, with most leveraging QSP to address efficacy (66.2%) and safety (33.8%) and a strong emphasis on dose optimization strategies . In addition, submissions in multiple therapeutic areas have included QSP analyses with onco...
[3]

Guideline to harmonise Model-Informed Drug Development General Principles (MIDD)

(ICH), International Council for Harmonization. Guideline to harmonise Model-Informed Drug Development General Principles (MIDD). s.l. : https://ich.org/page/multidisciplinary-guidelines#15, 2026

2026
[4]

Quantitative systems pharmacology: Landscape analysis of regulatory submissions to the US Food and Drug Administration

Bai JPF, Earp JC, Florian J, Madabushi R, Strauss DG, Wang Y, Zhu H. Quantitative systems pharmacology: Landscape analysis of regulatory submissions to the US Food and Drug Administration. CPT Pharmacometrics Systems Pharmacology. December 2021, pp. 1479-1484

2021
[5]

Landscape of regulatory quantitative systems pharmacology submissions to the U.S

Bai JPF, Liu G, Zhao M, Wang J, Xiong Y, Truong T, Earp JC, Yang Y, Liu J, Zhu H, Burckart GJ. Landscape of regulatory quantitative systems pharmacology submissions to the U.S. Food and Drug Administration: An update report. CPT Pharmacometrics Systems Pharmacology. December 2024, pp. 2102-2110

2024
[6]

Consideration of a Credibility Assessment Framework in Model-Informed Drug Development: Potential Application to Physiologically-Based Pharmacokinetic Modeling and Simulation

Kuemmel C, Yang Y, Zhang X, Florian J, Zhu H, Tegenge M, Huang SM, Wang Y, Morrison T, Zineh I. Consideration of a Credibility Assessment Framework in Model-Informed Drug Development: Potential Application to Physiologically-Based Pharmacokinetic Modeling and Simulation. CPT Pharmacometrics Systems Pharmacology. January 2020, pp. 21-28

2020
[7]

Physiologically Based Pharmacokinetic Analyses — Format and Content Guidance for Industry

FDA. Physiologically Based Pharmacokinetic Analyses — Format and Content Guidance for Industry. s.l. : https://www.fda.gov/regulatory-information/search-fda-guidance-documents/physiologically-based- pharmacokinetic-analyses-format-and-content-guidance-industry, 2018

2018
[8]

Reporting of physiologically based pharmacokinetic (PBPK) modelling and simulation - Scientific guideline

(EMA), European Medicines Agency. Reporting of physiologically based pharmacokinetic (PBPK) modelling and simulation - Scientific guideline. s.l. : https://www.ema.europa.eu/en/reporting- physiologically-based-pharmacokinetic-pbpk-modelling-simulation-scientific-guideline, 2019

2019
[9]

The simcyp population based simulator: architecture, implementation, and quality assurance

Jamei M, Marciniak S, Edwards D, Wragg K, Feng K, Barnett A, Rostami-Hodjegan A. The simcyp population based simulator: architecture, implementation, and quality assurance. In Silico Pharmacol. June 2013, pp. 1-9

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[10]

Using Quantitative Approaches to Optimize Dosages for New Combinations and Subsequent Indications for Oncology Drugs

Gao W, Liu J, Musante CJ, Zhu H, Thompson M, Shah M, Cao Y, Ivaturi V, Conaway MR, Bottino D, Yin D, Semiond D, Oganesian A, Ratain MJ, Li C, Zhu L, Ou YC, Jiang X, Vallejo J, Madabushi R, Liu Q, Theoret M, Rahman A, Booth B, Okusanya O, Johnson-Williams. Using Quantitative Approaches to Optimize Dosages for New Combinations and Subsequent Indications for...

2025
[11]

An industry perspective on current QSP trends in drug development

Cucurull-Sanchez, . An industry perspective on current QSP trends in drug development. J Pharmacokinet Pharmacodyn. 2024, pp. 511-520

2024
[12]

Evaluation framework for systems models

Braakman Sietse, Pathmanathan Pras, Moore Helen. Evaluation framework for systems models. CPT Pharmacometrics Syst Pharmacol. 2022, Vol. 11, 3, pp. 264-289

2022
[13]

Assessing the performance of QSP models: biology as the driver for validation

Fulya Akpinar Singh, Nasrin Afzal, Shepard J Smithline, Craig J Thalhauser. Assessing the performance of QSP models: biology as the driver for validation. J Pharmacokinet Pharmacodyn. October 2024

2024
[14]

The Drug-Dosing Conundrum in Oncology-When Less is More

Shah Mirat, Rahman Atiqur, Theoret Marc R, Pazdur Richard. The Drug-Dosing Conundrum in Oncology-When Less is More. The New England Journal of Medicine. 2021, Vol. 385, pp. 1445-1447. 8 Appendix APPENDIX FIGURE 1 CASE STUDY EVALUATION RUBRIC APPENDIX FIGURE 2 ANONYMIZED CASE STUDIES FROM WORKING GROUP APPENDIX FIGURE 3 PUBLISHED FDA MULTIDISCIPLINARY REVI...

2021