Evidence map›Paper›PMID 41571418›Full record

ArticleBMJ open2026

Haemoglobin vesicles as artificial red blood cells developed for use as a transfusion alternative: an open-label, single-centre phase Ib study protocol in Japan.

Kazuya Sakai, Kiyoshi Asada, Yudai Watanabe, Hiroshi Azuma, Hiromi Sakai, Masato Kasahara, Masanori Matsumoto

Abstract readClinical Trial Protocol
In one paragraph

Article in BMJ open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Kazuya SakaiDepartment of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan.ORCID http://orcid.org/0000-0003-0523-7931
Kiyoshi AsadaInstitute for Clinical and Translational Science, Nara Medical University Hospital, Kashihara, Japan.
Yudai WatanabeInstitute of Health Science Innovation for Medical Care (HELIOS), Hokkaido University Hospital, Sapporo, Japan.
Hiroshi AzumaDepartment of Pediatrics, Asahikawa Medical University, Asahikawa, Japan.
Hiromi SakaiDepartment of Chemistry, Nara Medical University, Kashihara, Japan.
Masato KasaharaInstitute for Clinical and Translational Science, Nara Medical University Hospital, Kashihara, Japan.
Masanori MatsumotoDepartment of Blood Transfusion Medicine, Nara Medical University, Kashihara, Japan mmatsumo@naramed-u.ac.jp.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

introductionHaemoglobin vesicles (HbVs) (product name, NMU-HbVs [Nara Medical University-Haemoglobin Vesicles]), which contain purified human haemoglobin encapsulated within liposomes, have been developed as a potential alternative to blood transfusions in emergency situations. A previous phase I study examined doses up to 100 mL in 11 healthy volunteers. Here, we describe the protocol for a phase Ib study, wherein we will evaluate the safety and pharmacokinetics of NMU-HbV in healthy Japanese adults. METHODS AND ANALYSIS: This single-centre, open-label, dose-escalation study will enrol 16 healthy volunteers divided into four cohorts. Planned doses are 100 mL for cohorts 1 and 2, 200 mL for cohort 3 and 400 mL for cohort 4, with infusion rates gradually increasing to a maximum of 5.0 mL/min. The primary endpoint will be safety, which will be assessed as the incidence of adverse events within 14 days and significant clinical changes within 72 hours after administration. Safety evaluations will include subjective symptoms, vital signs, electrocardiograms and laboratory test results compared with the baseline. The secondary endpoint will be pharmacokinetics, which will be assessed as changes in NMU-HbV concentration immediately after infusion until day 4 to determine the maximum blood concentration, time to reach the maximum blood concentration, area under the blood concentration-time curve and elimination half-life. This study will provide data on the safety and pharmacokinetic profiles of NMU-HbV at doses up to 400 mL. The findings are expected to support the further development of NMU-HbV as a viable alternative to emergency transfusions. ETHICS AND DISSEMINATION: The study protocol was approved by the Institutional Review Board of Nara Medical University on 10 December 2024. Dissemination plans include publishing in peer-reviewed scientific journals and presentation at international conferences. TRIAL REGISTRATION NUMBER: Japan Registry of Clinical Trials (jRCT2051240249). Registered on 27 January 2025 (https://jrct.mhlw.go.jp/en-latest-detail/jRCT2051240249).

Indexed as

Blood SubstitutesHemoglobinsAdultClinical Trials, Phase I as TopicFemaleHealthy VolunteersHumansJapanLiposomesMaleYoung AdultBlood SubstitutesHemoglobinsLiposomesBlood bank & transfusion medicineClinical TrialEmergency Service, Hospital

Identifiers

PMID41571418
PMCPMC12829376

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.