Rigor Reviewed

Rigor-Reviewed Manuscript

Anticoagulation with osocimab in patients with kidney failure undergoing hemodialysis: a randomized phase 2 trial.

Name: Αlpha¹ Rigor Record — Anticoagulation with osocimab in patients with kidney failure undergoing hemodialysis: a randomized phase 2 trial.
Item: Anticoagulation with osocimab in patients with kidney failure undergoing hemodialysis: a randomized phase 2 trial.
Rating: 39
Author: Αlpha¹

Weitz JI, Tankó LB, Floege J, Fox KAA, Bhatt DL, Thadhani R, Hung J, Pap ÁF, Kubitza D, Winkelmayer WC, CONVERT Investigators

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Αlpha¹ Rigor Review — 1★ (Critical), 6 critical, 2 high issues for “Anticoagulation with osocimab in patients with kidney failure undergoing hemodialysis: a randomized phase 2 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

1 / 5

Critical — a demonstrable failure

Interventional Study

Critical

High-priority

How this rating was calculated▸

Started at 5★ — deductions

StatisticsImpossible or misreported statistic ×6−6★
ClaimsEfficacy rests on an unvalidated surrogate endpoint−0.5★
ClaimsTreatment effect not shown to be clinically meaningful−0.5★

A demonstrable critical failure caps the rating at the minimum, regardless of the deductions above.

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

Not verified in this report

The numeric-impossibility checks (GRIM/GRIMMER/DEBIT/SPRITE) did not run: 3 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 surfaced4 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.

Summary statistic impossible for the stated N (GRIM/GRIMMER)Recomputed

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

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.

Critical findings

• PERCENT: 84.7% does not match the reported count 199/232
• PERCENT: 82.9% does not match the reported count 194/224
• PERCENT: 87.7% does not match the reported count 206/230
• PERCENT: 75.5% does not match the reported count 178/232
• PERCENT: 74.4% does not match the reported count 174/224
• PERCENT: 74.9% does not match the reported count 176/230

The paper is a well-conducted phase 2b randomized trial with rigorous design, clear reporting of demographics, ethics, and statistical methods. The main weakness is the absence of a formal sample size calculation, which is acknowledged and typical for phase 2. Minor copyedit issues exist in tables and a potentially misleading operational expectation statement.

Both reviewers agreed on all dimensions and study type (interventional). The statistics verification component recomputed only a subset of tests (2 of 8 consistent); the remaining tests were not machine-verifiable and are not confirmed. The citation check found no retracted or unresolved references. The reproducibility check found all links live.

7 major claims checked against the paper's own evidence: 2 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.

Recomputed 2 tests: 2 consistent, 0 inconsistent; 2 via agent-written checks. 6 reported summary statistics mathematically impossible for the stated N (PERCENT).

Reporting

Eight Dimensions8 pass

The introduction cites multiple studies on the risks of anticoagulation in kidney failure, the role of factor XI in thrombosis, and prior osocimab trials. The rationale for the trial is clearly linked to the unmet need for safer anticoagulants. Limitations of prior research (e.g., underpowered apixaban trials) are acknowledged and addressed by the trial design.

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 with extensive prior work and a logical rationale for targeting factor XIa in hemodialysis patients.

Evidence

paraphrase[Introduction, paragraphs 1-3]

“Inhibitors of factor XI or its activated form, factor XIa, may be safer than the currently available anticoagulants because factor XI seems to be more important for thrombosis than for hemostasis.”

paraphrase[Introduction, last paragraph]

“To address the unmet need for safer anticoagulants for patients with end-stage kidney disease, we conducted the CONVERT trial...”

paraphrase[Discussion, paragraph 4]

“Two randomized trials comparing vitamin K antagonists with apixaban in individuals with kidney failure undergoing hemodialysis who had atrial fibrillation were able to recruit only 154 and 97 participants, respectively, and were therefore underpowered to yield definitive results.”

PASSReviewer 2· 90% conf

The paper establishes a clear scientific premise: patients on hemodialysis have high thrombotic risk but also high bleeding risk with current anticoagulants, and factor XIa inhibition may offer a safer alternative. Prior work on osocimab and factor XI is cited, and the rationale for the trial is well articulated.

Evidence

paraphrase[Introduction, paragraph 2]

“In a phase 2 dose-finding study in individuals undergoing total knee arthroplasty, a single intravenous dose of osocimab administered before surgery was superior, or after surgery was noninferior, to enoxaparin for prevention of postoperative venous thromboembolism.”

direct quote[Introduction, paragraph 1]

“Therefore, with limited evidence supporting the use of warfarin or direct oral anticoagulants in this patient population, there remains an unmet need for safer anticoagulants for the prevention of thromboembolic events.”