Efficacy of Lactococcus lactis Strain Plasma in Patients with Mild COVID-19: A Multicenter, Double-Blinded, Randomized-Controlled Trial (PLATEAU Study)

DOI record: { "DOI": "10.1007/s40121-025-01246-8", "ISSN": [ "2193-8229", "2193-6382" ], "URL": "http://dx.doi.org/10.1007/s40121-025-01246-8", "alternative-id": [ "1246" ], "assertion": [ { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "Received", "name": "received", "order": 1, "value": "17 August 2025" }, { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "Accepted", "name": "accepted", "order": 2, "value": "2 October 2025" }, { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "First Online", "name": "first_online", "order": 3, "value": "25 October 2025" }, { "group": { "label": "Declarations", "name": "EthicsHeading" }, "name": "Ethics", "order": 1 }, { "group": { "label": "Conflict of Interest", "name": "EthicsHeading" }, "name": "Ethics", "order": 2, "value": "Kazuko Yamamoto received research funds from Kirin Holdings Co., Ltd. for this study and another research grant from Fisher & Paykel Healthcare Ltd. Tsuyoshi Inoue received research funds from Kirin Holdings Co., Ltd. for this study. It belonged to a donated course from Kyowa Kirin Co., Ltd. Kenta Jounai, Ryohei Tsuji, and Daisuke Fujiwara are employees of Kirin Holdings Co. Ltd. Koichi Izumikawa received a research grant for this study from Kirin Holdings Co., Ltd. Hiroshi Mukae received a research grant from Taisho Pharmaceutical Co. Ltd. All funding agencies, except Kirin Holdings Co., Ltd., played no role in the study design, data collection and analysis, decision to publish, or manuscript preparation. Takaya Ikeda, Toyomitsu Sawai, Yosuke Nagayoshi, Koji Hashiguchi, Yoji Futsuki, Yuichi Matsubara, Yosuke Harada, Nobuyuki Ashizawa, Susumu Fukahori, Naoki Iwanaga, Takahiro Takazono, Takashi Kido, Hiroshi Ishimoto, Naoki Hosogaya, Noriho Sakamoto, Masato Tashiro, Takeshi Tanaka, Chizu Fukushima, Kenji Ota, Kosuke Kosai, Akitsugu Furumoto, and Katsunori Yanagihara declare no conflicts of interest." }, { "group": { "label": "Ethical Approval", "name": "EthicsHeading" }, "name": "Ethics", "order": 3, "value": "The study protocols were inspected and approved (approval no. CRB21-009) in November 2021 by the Clinical Research Review Board of Nagasaki University. This study was registered with the Japan Registry of Clinical Trials (jRCT) (registration number: jRCTs071210097) in December 2021. The trial protocol has been described previously [\n \n ]. Patient enrollment was conducted from December 2021 to April 2022. The study was conducted in accordance with the Declaration of Helsinki, Clinical Trials Act, and other current legal regulations in Japan. Written informed consent was obtained from all enrolled patients who met the eligibility criteria before the intervention. To avoid bias and ensure quality, a third-party entity (Soiken, Inc., Osaka, Japan) performed data collection, management, monitoring, audits, and statistical analyses." } ], "author": [ { "ORCID": "https://orcid.org/0000-0002-1357-1676", "affiliation": [], "authenticated-orcid": false, "family": "Yamamoto", "given": "Kazuko", "sequence": "first" }, { "affiliation": [], "family": "Inoue", "given": "Tsuyoshi", "sequence": "additional" }, { "affiliation": [], "family": "Ikeda", "given": "Takaya", "sequence": "additional" }, { "affiliation": [], "family": "Sawai", "given": "Toyomitsu", "sequence": "additional" }, { "affiliation": [], "family": "Nagayoshi", "given": "Yosuke", "sequence": "additional" }, { "affiliation": [], "family": "Hashiguchi", "given": "Koji", "sequence": "additional" }, { "affiliation": [], "family": "Futsuki", "given": "Yoji", "sequence": "additional" }, { "affiliation": [], "family": "Matsubara", "given": "Yuichi", "sequence": "additional" }, { "affiliation": [], 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