Rigor Reviewed

Rigor-Reviewed Manuscript

Sustained effect of prasinezumab on Parkinson's disease motor progression in the open-label extension of the PASADENA trial.

Name: Αlpha¹ Rigor Record — Sustained effect of prasinezumab on Parkinson's disease motor progression in the open-label extension of the PASADENA trial.
Item: Sustained effect of prasinezumab on Parkinson's disease motor progression in the open-label extension of the PASADENA trial.
Rating: 96
Author: Αlpha¹

Pagano G, Monnet A, Reyes A, Ribba B, Svoboda H, Kustermann T, Simuni T, Postuma RB, Pavese N, Stocchi F, Brockmann K, Smigorski K, Gerbaldo V, Fontoura P, Doody R, Kerchner GA, Brundin P, Marek K, Bonni A, Nikolcheva T, PASADENA Investigators, Prasinezumab Study Group

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Αlpha¹ Rigor Review — 2★ (Weak), 0 critical, 4 high issues for “Sustained effect of prasinezumab on Parkinson's disease motor progression in the open-label extension of the PASADENA trial.”

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Αlpha¹ Editorial

This rigor review was examined and confirmed by Αlpha¹ Editorial · August 16, 2026

Αlpha¹ Rigor Review

Rigor Reviewed

2 / 5

Weak — serious problems found

Observational Study

Critical

High-priority

How this rating was calculated▸

Started at 5★ — deductions

IntegrityIntegrity concern ×2−1★
ClaimsEfficacy rests on an unvalidated surrogate endpoint−0.5★
ClaimsTreatment effect not shown to be clinically meaningful−0.5★
LinksDead data/code link ×2−0.5★
ReportingStudy design partially met−0.25★
CitationsUnresolved reference−0.25★

Model-reported confidence: highReviewer agreement: highEngine: 7.39.0Source: full text

Not verified in this report

No reported statistical tests were found to recompute.
The numeric-impossibility checks (GRIM/GRIMMER/DEBIT/SPRITE) did not run: 10 reported means were read, and their group size is not stated where the values are printed (this source has no machine-readable table structure). These checks need the count the mean was averaged over, so none was performed.

Problems surfaced8 types

Numerical inconsistencies1

Values that contradict each other or are impossible for the stated sample: recomputed p-values and test statistics, GRIM/GRIMMER checks on summary numbers, percentages against their own counts, totals against their parts, and estimates against their own confidence intervals.

Internal contradictions in the reported numbersAssessed

Overstated conclusions3

Conclusions that reach past what the paper's own results support — including a significance claim that no longer holds when the statistic is recomputed, and efficacy resting on an unvalidated surrogate endpoint.

Efficacy rests on an unvalidated surrogate endpointAssessed
Treatment effect not shown to be clinically meaningfulAssessed
Conclusions only partially backed by the presented evidenceAssessed

Data authenticity concerns1

An adversarial read for patterns associated with data that may not be genuine: results that look too clean, implausibly large effects, duplicated data or images, and methods that do not match the results reported.

Methods and results do not matchAssessed

Reporting gaps1

Required detail the manuscript never states — study design, biological variables, ethics approval and consent, key resources, statistical reporting, data and code availability, and overall transparency.

Study-design details incomplete (controls, blinding, power)Assessed

Broken references and links2

References checked against Crossref, OpenAlex and Retraction Watch for retractions and resolvability, plus declared data and code links probed for whether they resolve to content matching the paper.

Dead data/code linksRecomputed
References not resolvable to a published paperRecomputed

This Αlpha¹ Rigor Review uses AI Rigor Reviewers trained on a curated corpus of high-fidelity and retracted papers, with expert supervision and curation. It can still make mistakes; verify each finding against the source before relying on it.

The paper is a well-conducted observational comparison of an open-label extension with an external comparator, with strong reporting of methods, ethics, and data availability. The main weaknesses are the lack of a pre-specified analysis plan, no power analysis, and incomplete reporting of outlier handling and code sharing.

The reviewers disagreed on study type (observational vs. interventional); I adopted 'observational' because the primary analysis is a comparison of an OLE cohort with an external observational cohort, not a randomized intervention. The statistics verification component found no recomputable tests, so statistical correctness is not fully confirmed.

9 major claims checked against the paper's own evidence: 5 only partially supported (evidence backs part of the claim; gaps or caveats remain); the rest adequately supported.

Premise concern: surrogate not validated for clinical benefit; effect size not shown to be clinically meaningful.

2 integrity concerns flagged (0 high).

Reporting

Eight Dimensions7 pass · 1 warn

The introduction cites prior studies on α-synuclein aggregation and the development of prasinezumab, including the PASADENA Phase II trial. It acknowledges that the primary endpoint was not met in the double-blind period but that motor progression was reduced. The rationale linking the premise to the study objectives is logical: to evaluate whether the effect on motor progression is sustained long-term. Limitations of prior research (e.g., lack of long-term data, placebo arm in OLE) are addressed in the discussion.

Sub-criteria

prior work citedADEQUATE

premise rationaleADEQUATE

limitations addressedADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The paper establishes a clear scientific premise based on prior work on alpha-synuclein and prasinezumab, and provides a logical rationale for the study.

Evidence

paraphrase[Introduction, paragraph 1]

“Prasinezumab is a humanized monoclonal antibody designed to bind aggregated α-synuclein and inhibit the intercellular spread of pathogenic α-synuclein, thus potentially protecting neurons and slowing Parkinson’s disease (PD) progression.”

paraphrase[Introduction, paragraph 2]

“The PPMI was used to put into context the rates of disease progression seen in the OLE of PASADENA, in the absence of a placebo group beyond PASADENA Part 1.”

paraphrase[Discussion, paragraph 2]

“Using a well-established method of propensity score balancing of baseline characteristics, we matched the trial and comparator groups.”

PASSReviewer 2· 95% conf

The paper clearly establishes the scientific premise by citing prior work on α-synuclein aggregation in Parkinson's disease and the rationale for immunotherapy, and acknowledges limitations of prior research.

Evidence

direct quote[Introduction, paragraph 1]